VETERINARY STUDIES jrt^g^ THE MACMILLAN COMPANY NEW YORK • BOSTON • CHICAGO • DALLAS ATLANTA ■ SAN FRANCISCO MACMILLAN & CO., Limited LONDON • BOMBAY ■ CALCUTTA MELBOURNE THE MACMILLAN CO. OF CANADA, Ltd. TORONTO Ill,'''' J ' > > J 5 , ' 1 J > 3 1 5 _ i 5 1 VETERINARY STUDIES FOR AGRICULTURAL STUDENTS BY M. H. REYNOLDS, B.S., D.Y.M, M.D. PROFESSOR OP VETERINARY MEDICINE, UNIVERSITY OF MINNE- SOTA; MEMBER INTERNATIONAL COMMISSION ON CONTROL OF BOVINE TUBERCULOSIS; MEMBER AMERICAN VETERINARY MEDICAL ASSOCIATION EIGHTH EDITION THE MACMILLAN COMPANY 1922 All Rights Reserved %', ; Jr' ; ^^'f 'r,.' '* I ^/'^ /'paiNTJSD IN THE UNITED STATES OF AMERICA G Copyright, 1910, and 1922, By the MACMILLAN COMPANY, Set up and electrotyped. Published December, 1910. Reprinted August, 1911. Eighth edition. — Set up and electrotyped. Published November, 1922. kviAlM LIBRAKY. AGRICULTURE DEKV PREFACE TO EIGHTH EDITION I WISH to thank my many fellow teachers who have shown appreciation by continuing to use this textbook in spite of inac- curacies and evident need of revision. I wish to emphasize again the fact that Veterinary Studies is intended to some extent as a teacher's outline. Each teacher must add material as he may think wise, or leave out entire subjects according- to local needs. I find that very many pupils taking veterinary class work in ag- ricultural schools need review work on physiology. The necessity for a practical working knowledge of physiology is evident. Some knowledge of anatomy is plainly necessary in order that disease processes may be located, and that students may under- stand animal conformation. Some elementary pathology is absolutely necessary in order that pupils may have some under- standing of what disease processes really are. Causes and prevention of diseases should be considered as of paramount importance, and only carefully selected diseases should be presented. These should be diseases which are uniform in symptoms and history and therefore easily recognized, and of such diseases, those that are rather easily and simply treated or are preventable. There may be perhaps exception to this, in case of stock owners who do not have access to trained veterinarians. In such case it is a matter of plain common sense that they must do the best they can for themselves. However, we veterinary teachers of agi-icultural students should have constantly in mind the fact that we are educating expert stockmen — not poorly trained quack veterinarians. The student who has had a proper course should better appreciate the competent veterinarian and call him more promptly and intelligently. Appreciation is due JP. f^ A 1Iewitt,"Tr£ the College of Agri- culture, University of ATiiiuoula, for' >e^ wing and criticizing the lectures on anatomy and phvsiologv. 4083S2 ^^ *^ M. II. REYNOLDS. University of Minnesota, September, 1922. PKEFACE TO FIRST EDITION During ten years' experience in teaching veterinary subjects to agricultural students, certain difficulties have l)cen constantly encountered. Others doing this work have probably had similar experience. There has been the difficulty of imperfect training, or entire lack of previous training, in physiology and other sub- jects which medical men recognize as fundamental. There is always present the difficulty of presenting a technical subject in untechnical language ; difficulty in securing satisfactory illus- trations; and difficulty in giving the kind and character of veterinary work which is generally demanded and conceded as necessary, without giving our students a sort of training which will turn some of them into unqualified practitioners. There has been serious difficulty in covering, without a textbook, a sat- isfactory amount of ground. Many students do not take notes well. During this time I have been more and more impi-essed with the belief that a textbook, wisely illustrated and carefully edited for its legitimate use, would enable me to cover very much more ground within the available time. The style of editing that has been adopted was selected with a view to presenting the subject matter to students in a con- spicuous and easily grasped way. This must be our excuse and answer to criticism which the expert printer may legitimately make. This work has been written more particularly as a text for veterinary classes in agricultural schools and colleges; but it is hoped that it may prove helpful also to stockmen who are not able to attend our agricultural colleges, but who care to know more of the animal machines with which they are working. I take this occasion to deprecate the blind dosing of stock to which farmers and stockmen are very much inclined. The student should realize the impossibility of writing a prcscrii)tion that will vii viii PREFACE TO FIRST EDITION fit all cases of a certain disease, and he will hesitate to risk the use of medicines of which he knows very little in diseases of which he knows less. Lecture notes which have been collected during a period of ten years have formed the basis for this w^ork, and I am now unable, in many cases, to give credit to authorities that have been con- sulted, where credit is fairly due. Illustrations have not been used in any case merely as pic- tures. Every one is intended to illustrate something and make that illustration as impressive as possible. Suggestions to the teacher. It is not intended that this text- book should entirely supplant lecture work. On the contrary, nearly every lesson may be supplemented to advantage and so give opportunity for originality and the greatest effectiveness. It will be readily understood that certain subjects are of great importance in some states, and unimportant in others. Each teacher should add what he thinks best for his grade of pupils and his local needs. "When time permits much time can be profitably spent on more extended anatomy work, especially for students who wish advanced live stock work. It can be readily illustrated and easily impressed : for instance, that smooth or rough hips de- pend upon a fraction of an inch, more or less, on the external angle of the ilium ; and that high or low" withers, in the main, depend upon variations in the length of the superior spinous processes of the dorsal vertebrae ; and that conformation depends upon the bony skeleton and muscular developments. IVIuch time with considerable actual practice should be given to the study of unsoundness ; to common forms of lameness, and the types of conformation which tend toward these unfortunate conditions. Common irregularities of the teeth are easily illus- trated in classroom. These are given as suggestions and to im- press the fact that this text is not expected to cover the entire field of veterinary teaching for all agricultural colleges. I respectfully suggest that teachers should insist upon study of illustrations. In my own class work I find the constant diffi- culty that students glance at the illustrations carelessly and hurriedly, and thus fail to get the benefit which they might easily have. Students may be selected at random and asked to PREFACE TO FIRST EDITION ix draw upon the board, from memory, illustrations from the les- son for that day. After a few practice lessons of this kind, students easily learn how to study textbook illustrations. M. H. REYNOLDS. University of Minnesota, October, 1903. CONTENTS ANATOMY LECTURE PAGE I. ANATOMY Bones. — Kinds, peculiarities, development, structure and composition. Head. — Face, cranial, and hyoid bones; dentition of horses, table; dentition of cattle, table; estimating age by teeth; original application, common disorders 1 II. OSTEOLOGY Spinal column. — General characteristics of vertebrae. Cervical, dorsal, lumbar, sacral, and coccygeal ver- tebrae. Sternum. Eibs. Practical application, common dis- orders 7 III. FRONT LIMB Shoulder, arm, forearm, and foot — bones of, common disorders 10 IV. POSTERIOR LIMB Pelvis, thigh, leg, and foot — bones of, practical applica- tion, disorders 14 V. FOOT Bones, horny hoof, matrix, plantar cushion, back ten- dons, good foot described, practical application, dis- orders of the foot 19 VI. ARTICULATIONS (JOINTS) General groups, examples; varieties of freely movable, immovable, slightly movable. Structures at joints; articulations described, practical application, disorders 24 VII. MUSCULAR SYSTEM Peculiar property of muscle, kinds, classification, parts, microscopic structure, source of heat and power, practical application, disorders 29 ^ii CONTENTS LECTURE PAGE VIII. NERVOUS SYSTEM General function, nerve centers. Cerebrospinal system. — Brain, cranial nerves, spinal cord, spinal nerves. Sympathetic system. — Composition, ganglia, sympathetic nerves, practical application. Disorders ^^ IX. CIRCULATION Blood. — Circulatory apparatus, course of the blood, blood supply of the body, principal arteries and veins. Lymphatic system. — Parts, function. Practical application, disorders 42 X. RESPIRATION Definition, stages, parts, purpose, respiratory apparatus, practical application, disorders 51 XL DIGESTIVE APPARATUS Definition, organs of digestion, anatomy of each, prac- tical application 57 XII. PHYSIOLOGY OF DIGESTION Definition of digestion, food groups, course and history of each group, practical application and suggestions 64 XIII. URINARY ORGANS Structure, function, and physiological operation of each, practical application, disorders 68 XIV. MAMMARY GLANDS Anatomy, function, products, blood supply, nerve supply, and nerve control, practical application, disorders . 72 PATHOLOGY XV. PATHOLOGY Hyperaemia (congestion), inflammation, fever, heat pro- duction and expenditure, symptoms of fever, results of fever, practical application 77 XVI. PATHOLOGY {Continued) Hemorrhage, dropsy, hypertrophy, atrophy, degenera- tions and infiltrations, collapse, syncope, death, ne- crosis, practical application '• 83 CONTENTS Xlll LECTURE XVII. XVIII. PAGE WOUNDS Healing, and development of new blood vessels. Healing of osseous, cartilage, and nerve tissues. New tissue, how skin recovers a surface 88 WOUNDS (Continued) Bad treatment, bleeding, sewing, bandaging, washing, dry treatment, maggots, practical suggestions 91 CAUSE AND PREVENTION XIX. CONTAGIUM The individual bacterium, plagues in history, dissem- ination, development of outbreaks, body entrance, method of injury, resistance, how destroyed in nature, classification, practical suggestions 96 XX. DISINFECTION Purpose, sources of infection, thoroughness, attendants, how to burn a carcass, common disinfectants, methods of disinfection 102 XXI. HEREDITY— AIR Theory of heredity in relation to disease, in-and-in breed- ing. Air impurities, relations to disease, standards of purity, ventilation, practical application 106 XXII. VENTILATION Stable air, necessity, unventilated air, natural forces, air currents, outlets 109 XXIII. VENTILATION {Continued) Stable construction. — Space, location, stable construc- tion for ventilation, ventilation, amount of air needed 114 XXIV FOOD AND WATER Food. — Excess, deficiency, bulk, quality, balance, inter- vals, poisonous foods. Water. — Excess, deficiency, parasites, sewage, intervals. Practical application 119 xiv CONTENTS PARASITIC DISEASES LKCTURE PAGl XXV. PAKASITISM Parasitism. — Sources, how nourished, effect on host, general prevention, general treatment, practical ap- plication. External Parasites. — Lice, flies, ringworm, sheep ticks, ticks, treatment and suggestions for each .... 124 XXVI. SHEEP SCAB Body scab, foot scab, head scab, general prevention, general symptoms, treatment, dips, dipping, disin- fection 130 XXVII. MANGE Horse mange and cattle mange, cause, symptoms, treat- ment of each 137 XXVIII. INTERNAL PARASITES Bets, roundworms, tapeworms, treatment ...... 141 XXIX. NODULE DISEASE OP SHEEP General history, cause, injury, diagnosis, treatment, prevention 145 XXX. STOMACH WORM (SHEEP) Parasite, life history, symptoms, treatment, drenching sheep, management of infected flock, prevention . 149 XXXI. VERMINOUS BRONCHITIS, NASAL GRUB, AND CATARRH Verminous bronchitis. — Cause, life history of parasites, symptoms, treatment, prevention. Nasal grub. — Cause, life history, symptoms, treatment. Catarrh. — Simple catarrh defined, causes, prevention, treatment 153 INFECTIOUS DISEASES XXXII. ACTINOMYCOSIS (LUMPY JAW) Description, relation to public health, parts involved, treatment 158 CONTENTS XV LECTURB ""AGE XXXIII. ANTHRAX History, distribution, susceptible animals, cause, trans- mission, introduction and spread, incubation, symp- toms, post mortem, diagnosis, vaccination .... 163 XXXIV. SYMPTOMATIC ANTHRAX Cause, symptoms, post mortem, prevention, vaccination 167 XXXV. BACILLUS NECROPHORUS INFECTIONS Explanation, cause, infection, foot rot, lip-and-leg ul- ceration, canker sore mouth, necrotic stomatitis, symp- toms, treatment, management, etc., for each . . . 170 XXXVI. FOOT-AND-MOUTH DISEASE Definition, symptoms, similar diseases, dissemination, prevention, treatment 177 XXXVII. HEMORRHAGIC SEPTICEMIA Etiology, history and development, symptoms, post mor- tem, summary, differential diagnosis 180 XXXVIII. TEXAS OR TICK FEVER Economic importance, causes, trananission, suscepti- bility, incubation, symptoms, post mortem, prognosis, treatment, prevention, tick extermination, vaccination 185 XXXIX. TUBERCULOSIS Prevalence, cause, modes of infection, structures af- fected, spiiptoms, diagnosis, treatment, prevention, summary, disposition of tuberculous cattle, accredited herd plan 192 XL. TUBERCULIN TEST FOR TUBERCULOSIS Tuberculin effect on health, accuracy, thermal, intra- dermal, and ophthalmic tests, importance to breeders 198 XLI. GLANDERS Susceptible animals, causes, incubation, symptoms, acute eases, chronic eases, farcy, diagnosis, mallein tests, prevention, suggestions 203 xvi CONTENTS LECTURE PAGE XLII. HOG CHOLERA Definition, symptoms, autopsy, cause, how scattered, vaccination, common mistakes, suggestions . . . 208 XLIII. COMMON MINOR DISEASES OF SWINE Posterior paralysis, congestion of the lungs, constipa- tion, cause, symptoms, treatment of each, drenching swine, suggestions 215 DIETETIC DISEASES XLIV. AZOTURIA Prevalence, history, parts affected, duration, causes, symptoms, prevention, treatment, prognosis . . . 218 XLV. LYMPHANGITIS (ELEPHANT LEG) Cause, symptoms, prevention, treatment, prognosis . . 222 XLVI. LAMINITIS (FOUNDER) Definition, symptoms, cause, pathology, termination, prevention, treatment 224 XLVII. HEAVES Definition, cause, symptoms, prevention, post mortem, treatment 227 XLVIIL HOVEN, OR BLOAT (ACUTE TYMPANITES) Definition, causes, symptoms, treatment, prevention . 230 XLIX. PARTURIENT PARALYSIS (MILK FEVER) Causes, symptoms, prevention, treatment, prognosis . 233 L. CHOKE Explanation, symptoms, prevention, treatment, general suggestions 238 MISCELLANEOUS DISEASES LL UNSOUNDNESS Unsoundness, normal condition, ringbone, sidebone, spavin, splints, curb, bog spavin, open joint, hygromas, miscellaneous unsoundness 241 CONTENTS xvii LECTURE LII. PAGE UNSOUNDNESS {Continued) Examination at rest, in motion, examination in detail. Lameness. — Locating lameness, tests 249 OBSTETRICS LIII. OBSTETRICS Organs described, normal periods of gestation. Accidents of pregnancy. — Sporadic abortions, infectious abortions, symptoms, results 254 LIV. OBSTETRICS (Continued) Infectious abortion. — Causes, virus, dissemination, in- fection, results, importance, various classes of stock, diagnosis, prevention, management of aborting herd, disinfection, medical treatment, vaccines, calves . . 259 LV. OBSTETRICS {Concluded) Accidents of pregnancy. — Eetention of fetus, volvulus, or twist. Accidents of parturition. — Infection, inflammation of the uterus, inversion of the uterus, retention of the afterbirth, hemorrhage 264 LVI. DISORDERS OF THE UDDER Garget. — Definition, causes, symptoms, results, preven- tion, treatment. Udder diseases and accidents. — Injuries, obstruction, warts, eowpox, etc 269 LVII. DIFFICULT PARTURITION Difficult parturition. — Nature's plan, normal presenta- tions, causes of difficulty, common faulty presenta- tions, aid, suggestions, operations 274 MEDICINES LVIII. COMMON MEDICINES Common measurements and weights, giving medicines, various common medicines as to physiological effects, doses and uses 280 sviii CONTEXTS LEC PAGE LIX. COMMOX MEDICIXES (Continued) Various common medicines, as to physiological effects. doses and uses --^ LX. COMMOX MEDICIXES ^Concluded) Various common medicines, physiological effects, doses and uses 287 MINOR SURGICAL OPERATIONS LXI. MIXOR SUEGICAL OPERATIOXS Castration, various kinds of stock- Dehorning, by caus- tic, shears, saw. Docking. Draining abscess. Semoc- ing varts. lapping for hloot 291 ILLUSTRATIONS PAGE T Skeleton. B.A.I ^«^'"^ ^ o 2. Horse Skull. Chcuieau 3. Teeth of Horse 6 Years Old (Lower Jaw) ^ 4. Teeth of Horse 8 Years Old (Upper Jaw). Oarke .... 4 5. Teeth of Horse 20 Years Old (Lower Jaw). Clarke .... 5 6. Grinding Surface of Molars. Euidekoper ^ 7. Typical Cervical Vertebra. Chauveau ' 8. Typical Dorsal Vertebra (Front View). Chauveau .... 8 9. Typical Lumbar Vertebra (Front View). Cliauveau .... 8 10. Lateral View of the Sacrum. Chauveau ^ 11. Anterior Limb of the Horse. Chauveau H 12. Posterior Limb of the Horse. Chauveau 1-^ 13. Bones of the Horse 's Foot. Chauveau 19 14. The Hoof. Chauveau 15. The Hoof Matrix. Chauveau -^ 16. Voluntary Muscle. BeynoJds ^^ 17. Muscle Fibers. Hewes ^^ 18. The Cerebrospinal Nervous System. Magnin 33 19. Neuron ^^ 20. Medullated Nerve Fibers ^^ 21. Spinal Cord and Brain in Diagram. Beynolds 36 22. Relation of the Sympathetic and Cerebrospinal Systems, Partly Diagrammatic. Chauveau 38 23. Circulation, General View. Magnin 43 24. Circulation, Diagrammatic. No. 1, BeynoJds; No. 2, after Overton 44 25. CapiUary Circulation. Eddy •*5 26. The Lymphatic System (Human). Eddy 48 27. A Lymph Node. Eddy ^^ 28. Respiration in Diagram. Eeynolds 52 29. Stomach of the Horse (External and Internal Views). Chauveau 58 30. Stomach of the Cow. After Chauveau 59 31. Section of Horse Kidney. Chauveau 68 32. Urinary Apparatus in Diagram. Eeynolds 69 33. One Quarter and Teat of the Cow 's Udder. Tlianhoffer ... 72 xix XX ILLUSTRATIONS FIO. PAGE 34. Milk Vesicles and Outlet Ducts. Chauvecm 73 35. Badly Treated Wire Wound. Reynolds 91 36. General Groups of Bacteria. Reynolds 99 37. Ventilation. Paige 109 38. Ventilation. Paige 112 39. Ventilation. Paige 115 40. Cupola A^entilation. Paige 116 41. Ventilation. Paige 116 42. Cattle Louse (Female). Neuman . 126 43. Sheep Tick and Enlarged Proboscis. Neuman 128 44. Plain Case of Sheep Scab 131 45. Sheep Scab Mites. Curtice, Lugger, Pettit 132 46. Mange Mite. Neuman 137 47. Horse Botfly and Larva. Neuman 141 48. Horse Bots and Botfly. B. A. I 142 49. Common Tapeworm of Sheep. Curtice 144 50. Nodule Disease. Reynolds 146 51. Stomach Worm on Tip of Grass Blade. Ransom 149 52. Sheep Gadfly. Brauer 155 53. Actinomycosis (Lumpy Jaw). Reynolds 159 54. Actinomycosis. Reynolds 160 55. Actinomycosis. Reynolds 160 56. Bacterium Anthracis. Reynolds 163 57. Bacillus Necrophorus. B. A. I .... 170 58. Foot Eot (Sheep). Williams 171 59. Lip and Leg Ulceration. B. A. 1 175 60. Hemorrhagic Septicaemia. Reynolds 181 61. Hemorrhagic Septicaemia. Reynolds 182 62. Hemorrhagic Septicaemia. Reynolds 183 63. Hemorrhagic Septicaemia. Reynolds 184 64. Texas Fever Tick. Pettit 185 65. Bovine Tuberculosis. Reynolds 192 66. Bovine Tuberculosis. Reynolds 193 67. Bovine Tuberculosis. Reynolds 194 68. Bovine Tuberculosis. Reynolds 195 69. Glanders (Farcy). Reynolds 204 70. Glanders (Farcy). Reynolds 205 71. Glanders (Farcy). Reynolds . 206 72. Hog Cholera. Reynolds 209 73. Hog Cholera. Reynolds 210 ILLUSTRATIONS xxi FIG. f^«^ 74. Hog Cholera. Eeynolchi 211 75. Hog Cholera. Hetjuolds 212 76. Foundercil Hoof. B. A. 1 225 77. Showing Whore to Tap for Bloat. Beynolds 230 78. Trocar and Cannula 231 79. Parturient Paralysis. Reynolds 233 80. Parturient Paralysis. Ecynolds 234 81. Parturient Paralysis. Beynolds 235 82. Wire for Relieving Choke. Beynolds 239 83. Ringbones. Beynolds 243 84. Sidebones. Beynolds 243 85. Spavins (Two Types). Reynolds 244 86. Navicular Disease. Beynolds 247 87. Generative Organs of the Mare. Fleming 254 88. Fetus and Fetal ^^lenibranes of the Cow at Mid-pregnancy. Fleming 255 89. Bovine Cotyledons. Fleming 256 90. Presentations. B. A. 1 275 91. Holding Horse's Head for Drenching. Reynolds 281 92. Throwing Cattle. Beynolds 291 93. Restraint for Castration. White 292 94. General View of Scrotum and Sheath. White 292 95. A Good Type of Emasculator. White 293 VETERINARY STUDIES 2^ J-. c3 ,^ ^ X "=3 "So L~ ^ OJ t^ cd Qi'ta >» 71 C^ •"^ r^ =^ ^ •^ p- oi ^ CO ^13 «-<^ rt C « rt a ^ +J -rH 83 73 > « ^(M ^ ^ ci ^ .^ oj >^^-2 &. 6 tK CO ^ Hi -pis •'?3- -is ,2 ^i ctf CR cS k^ OS GO T— 1 r-; <^>''" V? c -t^ 2i -r^ X - <; 03 -^ --< >o --* rt S a " t> rt ^ X a,,n a " QJ '^^ Fig. 38. — Ventilation. (Paige.) Air Currents. Manger front inlet. ing facilities to compensate for this. The incoming air should not pass over, or through, any contaminating source, such as a manure pile, and it is very important that the general plan of construction should be well considered. Temperature and weight.— The second factor, difference in weight between the lighter warm and heavier cold air, is not so important in natural (windows and doors) as in artificial ventilation, and yet it is a factor of considerable importance. The heat which warms the air in the lower levels is that which comes from the bodies of the confined animals, as it is radiated from the surface or warmed in passing through the lungs. Diffxision of ^as^es.— Carbonic gas is considerably heavier than air, but the lower air levels usually do not usually show much more CO2 than the higher ones on account of diffusion, which takes place in response to the law of diffusion of gases — operat- ing independently of relative weights. This force is so strong VENTILATION 113 in its action that considerable diffusion takes place through lum- ber and ordinary brick, and other building materials. Air Currents An entering current of air has the effect of inducing other currents within the stable, tlie induced currents setting in at right angles to the inlet current. With AvhidoAVs wide open to windward, and openings on the other side of the stable closed, and with ridge ventilation, it is found ^ that the current of air rushes in, strikes tlie floor at a variable distance after spreading out somewhat, then rises and most of it passes out at the ridge. A current decreases rapidly in velocity after the first five or six feet from the inlet. The atmosphere immediately under the inlet is l)ut moderately dis- turbed. When opposite windows are open, the air comes in from the windward side, strikes the ground, rises again, and a consider- able portion passes directly out at the opposite side. But a sud- den change in the outside currents may temporarily reverse this series. The exact movement of air within the stable is varied, of course, by stall partitions and other obstructions. A strong wind passing over a stable provided with ventilating shaft has an outward suction effect, and this is increased by a properly constructed cap which does not permit the entrance of outside air from below. ' Paige. LECTURE XXIII YENTILATION— Continued Stable Construction Space needed. — A large space — 500 cubic feet or more per animal — is important; but this does not lessen the necessity for ventilation. The atmosphere in a large stable housing a given number of animals may become just as foul as that in a smaller stable with the same number of animals, the only difference being the length of time required to reach this condition. The larger space makes possible the admission of a sufficient amount of air, without such drafts as would be the result if the same amount of air per hour were admitted into a smaller stable. Location. — In order that a stable may be well lighted and well ventilated, it is necessary to exercise care in selecting the location and in planning the proportions of the building. One of the most desirable forms is that of a main part standing east and west and used in a general way for storage purposes, with one or two "ells" at right angles to this on the south. Such an arrangement gives a very satisfactory and well-protected yard on the south, and an even lighting to the various portions of the "ells" in which the animals are kept. When a stable ex- tends east and west, and is wide enough for two rows of stalls, the animals on the north side do not get much sunlight, and the general lighting of their portion of the stable is poor. Width. — To be capable of the best ventilation, a stable should not be over 25 to 30 feet in width ; and the lower the better within reasonable limits, when one is depending on ventilation by doors and windows. Windows. — In order to secure suitable ventilation in a build- ing of this kind, two sets of windows should be provided, at least one set on each side, or better still, two sets on each side, one above the other. Door should be opposite door, and window opposite window wherever practicable. Sweep of sunlight over floor and fixtures is most desirable. In general where one is depending upon natural ventilation, 114 VENTILATION 115 and the air is brought in cold, the inlet should be high ; the out- let may be either low or high, and controlled by a damper for cold weather. Outlets and inlets. — In cases where suitable outlets are pro- vided above, and the conditions are favorable, warmed air passes upward and out of the room or building ; but if such outlets are not provided, then heated air merely rises to the ceiling, cools, spreads out and descends, and no pure air can come in to take its place. Circular, straight tubes are preferable. It is esti- mated that a right-angle bend in an outlet diminishes the velocity of the outgoing air about one half. Where it is absolutely nec- essary that an outlet tube should change its course, it should be done in a curve or slight bend rather than at a right-angle. All parts of ventilator, shafts and tubes should l)e accessible for cleaning purposes, as it is not un- common for them to become so obstructed by cobwebs and dust as to be useless. In a general way, the outlet tube, if it must be near an outside wall, should be placed on the south side of the building in order to economize the heat of the sun in rendering it more effective. Central outlet tubes are generally more efficient, be- cause they cool the column of air less, and maintain the current velocity better. One or two outlet tubes are more efficient than a larger number and should be preferred whenever construction permits. :\Iany small inlets are always better than a few large ones, as they admit the same volume of air, and give it better distribu- tion, without direct currents. Wing describes a form of cupola ventilation which has been found quite satisfactory in providing air outlet for some barns (see Fig. 40). This cupola outlet seems always in operation. There is no chance for wind to blow in and force strong down drafts. When in working order, it serves always as an outlet. It is easily closed by a rope from the ground floor. Fig. 39. — Ventilation. (Paige.) 1. Air duct obstructed by cob- webs and dust. 2. Stationary outlet cowl to utilize the force of the wind for producing upward suction, and to prevent down draft. 116 VETERINARY STUDIES Fig. 40. — Cupola Ventilation. This cupola ventilator consists of a common cupola with doors on two opposite sides, hinged above. Connected with these doors, S, 0, is a light board B, cut in the middle and hinged. When this board is straight, it holds one or both doors partly open. If the wind blows against one side, that door closes and the lee side door opens. To close both doors pull down on the rope E. Sheringham windows. — The Sheringham window is simple and efficient for a stable of suitable construc- tion. The system consists essentially of windows hinged at the bottom and guarded at the sides so as to make troughs as the windows open inward. This gives an upward current, the air passing over the backs of the animals and settling down without direct current. There should pref- erably be two sets of windows on each side, the lower windows be- ing generally used for inlets on the windward side, and the higher windows for the outlets on the lee- ward side. This affords a simple, inexpensive, and easily manipulated method of ventila- tion, and may be combined with ventilating shafts. Outlet ventilating shafts should have openings near the ceiling, and also close to the floor, so that their use can be regulated according to season and tem- perature, the upper openings of the shaft being used in hot weather, and the lower openings in cold weather. Fig. 41. — Ventilation. (Paige.) 1. Sheringham window in section. 2. Sheringham window, opening inward, from outside. Seen VENTILATION 117 There should be a number of medium-sized or even small windows in this system, rather than a few large ones. The same amount of air can be allowed to enter through the small openings without direct draft and with much better distribution. For large and expensive stables there are systems of ventila- tion based upon Prof. King's work. Competent architects should be consulted concerning the plans or the Division of Agricultural Engineering at your state agricultural college. Amount of ventilation needed. — The horse passes about 45 cubic feet of air through the lungs per hour. This, then, would be the amount which the average horse would use if he were out in the open where the supply is inexhaustible. It is impos- sible to have the air of any occupied stable as pure as the out- side atmosphere. The purpose of ventilation is to come as near to this point as may be feasible. Air passing at the rate of 3 miles per hour, which is barely perceptible, through total openings equal to 1 foot square, ad- mits 15,840 cubic feet per hour. Inlet openings amounting to 4 square feet admitting a current of air moving at the average rate of 3 miles per hour under average weather conditions are estimated to provide sufficient ventilation for 20 cows. The following data will serve as a general guide : RELATIVE AMOUNT OP AIR BREATHED Horse 100 Cow 82 Hos- 32 Sheep 21 AIR NEEDED PER HOUR (King) Horse -^290 cubic feet Cow 3o42 " " Ho- v.m " " Sheep 917 " " Hen 35 " " Professor Stewart, University of Minnesota, has worked out the following useful data for low outside temperatures : The amount of air that should be pi-ovided per cow ])or hour is estimated by Stewart as follows: At — 10° F, 1800 cul)ic feet; at 0° F, 2400 ; at + 10° F, 3000. This assumes an indoor tem- perature of 35° to 37° F, and a stable of average construction. 118 VETERINARY STUDIES TOTAL OUTLET AREA NEEDED AT VARYING HEIGHTS (Stewart) Outlet 40 feet hiiili horse 24, cow 20 square inches, " 30 " " " 30, " 25 '' " " 20 " " " 36, " 30, hog 20, sheep 12 square inches. " 15 " " " 42, " 36, " 25, " 15 " " These figures also assume that the outlet tube is vertical and straight. If the outlet shaft is not vertical or straight, then the capacity should be increased accordingly. LECTURE XXIV FOOD AND WATER Food. — Food may be a factor in animal disease when it is excessive in amount, insnt^cient, too concentrated, too coarse, bulk}', and innutritions for the animal that receives it; when it is poor in quality, when given in a poorly balanced ration or at irregular or improper intervals, or to a very tired or hot ani- mal ; when carrying vegetable or animal parasites, or when sud- denly changed, as from poor to rich pasture ; and when poi- sonous. Excessive amount results in azoturia, heaves, colic, etc., among horses ; and in milk fever, etc., among cows. It favors the de- velopment of all febrile diseases. Only a certain amount of food can be absorbed or used ; the remainder causes trouble. Deficiency predisposes to all diseases that are favored by a lessened vitality. The deficiency may be total, or there may be one or more special deficiencies, for example, deticiency of vita- min}?, which are essential to normal growth, and health ; or de- ficiency of certain mineral matters, the lack of which impairs growth and development of framework. Such animals, particu- larly hogs, tend to "go down." Lack of iodin for the pregnant sow i)roduces pigs that are born without hair, weak and with goiter. Glanders and similar diseases are especially apt to oc- cur, or to increase in severity, among horses that are poorly fed. Deficiency in mineral matters predisposes toward certain dis- eases of bone. Deficiency of albumin results in loss of energy and strength, and animals so fed are apt to be languid and weak. Coarse, hulkij, and innutritimis food may cause colic, indiges- tion, heaves and impactions, particularly in animals with small stomachs, as the horse. Poor quality, hay cut too ripe or that has been rained on after cut, light oats, etc., causes tlie same disorders as deficienc}', and also favors colic, impactions, and anemia. 119 120 VETERINARY STUDIES A food may be poorly balanced and dangerous though very nutritious. Beans, wheat, oil meal, and cotton seed meal fed alone contain too much protein and not enough ash, fat and carbohydrates and crude fiber. When fed in the unbalanced ration, such excess of protein may cause febrile disturbances, diarrhea, congestion of the liver, azoturia and milk fever. A similar excess of carbohydrates or fats may cause an injurious deposition of fat under the skin into and between the fibers of voluntary muscles, or in the heart or liver. Excess of fats causes diarrhea and checks absorption. Faulty intervals interfere with digestion and thrift, and may cause such disorders as colic and impaction. Cows may be fed at longer intervals than horses; but both should be fed regu- larly. A horse that goes a long time without food and then gets an abundance is apt to have colic or founder. The calf that goes past its usual feeding time and then overeats, is very apt to have serious bowel trouble and remain unthrifty for a long time. Animal parasites infest several foods, e.g. stomach worms (of sheep) on grass. Sudden changes, from poor to rich pastures, favor hoven, im- paction, and blackleg. There are class' differences — some animals may eat with im- punity what others cannot. By first producing digestive dis- turbances, rich cereals may indirectly cause laminitis in horses, — not in cows however. Pigs can eat acorns freely ; but acorns are injurious to other animals. Paisonoiis food, such as poisonous plants, may cause heavy losses. Such plants are usually distasteful to stock and are not eaten unless animals are hungry, for example, when on scant pasture or after long shipment by rail. Such losses are nearly all preventable by wise management. "Wild cherry" and black cherry leaves and occasionally sorghum contain a deadly poison, prussic acid. As a rule cherry leaves are not eaten, but losses of cattle and sheep from such poisonous plants have been reported many times. The common sorghum plant sometimes contains the same poison as cherry leaves. Fortunately it is unusual for sorghum to be poisonous, but serious losses of cattle have occurred be- cause of it. It is safer to test a field of fodder sorghum by turning in only one or two animals the first day. FOOD AND WATER 121 Laurel leaves are poisonous and cause losses among sheep particularly. ^Yild larkspurs have caused heavy losses of cattle and sheep, especially on western ranges. WJiorlcd ))iilkwccd is very poisonous especially to sheep. ^Vatcr hemlock (-wild parsnip), is poisonous to all classes of stock, and of all plants likely to be eaten, is considered the most dangerous. Loco plants are poisonous. Their damage is of slow develop- ment. Horses, cattle and sheep on the western ranges are often poisoned by it. This plant is peculiar among stock poisons in that it creates a drug habit in stock similar to the opium habit of people. Roots, like sugar beets and mangels, are not poisonous, but when fed in excess — to sheep at least — are likely to cause seri- ous derangement of the urinary organs, with formation of cal- culi (stones) in the kidneys, ureters, or bladder.^ Water Water. — Water may be a factor in animal disease when it is excessive or deficient in amount; when it contains bacteria, e.g. the virus of glanders or of hog cholera ; or when it contains such low forms of animal life as intestinal parasites for example; when it has received sewage matter ; when it is very hard, when it is given at improper intervals or in large quantity soon after eating, or when it is given in large quantities to a very hot or tired horse. An excessive amount of water is said to lessen the digestibility of foods, increase tissue waste, and favor indigestion. A deficient water supply may cause impactions in cattle and lessen the excretions from skin and kidneys in horses. Horses need about 2 pounds and cows giving milk about 3.5 to 4 pounds of water per pound of dry food, the amount varying according to diet and condition of the atmosphere. Cows need much more tlian horses in proportion to weight and feed, and can usually be trusted to drink at tlieir own pleasure. Horses will fre- quently drink too much, especially when tired or liot. ^ Iowa Exp. Sta. Bui. 112. For detailed information concerning poison- ous plants, consult "Poisonous Plants" by Paniniel; also Bulletin 20, and Bulletin 57;1 — both relating to poisonous plants and published hj U. S, Dcpt. Agr. Bureau of Animal Industry. 122 VETERINARY STUDIES Bacteria frequently contaminate drinking water, which may thius serve as a source of transmission for many germ diseases; like anthrax, foot and mouth disease, hog cholera, and glanders. Animal paradtcs also contaminate the water supply, which serves to spread parasitic diseases, intestinal parasites, for example. Hard water may contain much calcium, magnesium, etc., and is said to cause indigestion, unthrifty conditions, and perhaps calculi. Intervals may be w^rong. Horses should be watered regu- larly and at as short intervals as convenient. They should not be given large quantities of water sooner than one hour after eating gi-ain. Much cold water interferes with digestion, and w^hen given to a very hot or tired horse may result in founder or indigestion. Practical application. — With this lesson in mind, the student should hereafter watch for milk fever cases to see if the cow has not been in good condition and rather heavily fed for a cow not milking, and lacking in exercise. He should be on the watch for azoturia (see Lect. XLIV) and learn whether the horse has not been idle and full fed during the day or so prior to illness. Note also whether there had not been a period of regular work on full feed before this idle period. He should also watch for cases of heaves among horses to determine whether such horses have been greedy eaters and heavily fed with dusty hay or other bulky food. It will be interesting for the student to be on the lookout for an outbreak of hog cholera in a herd that had access to a small pond or very sluggish stream, to see if there is not an unusually heavy loss in such a case. The very hot, very tired, or very hungry horse should be fed and watered cautiously, with small quantities, until he is in better condition. Sudden and radical changes from old to new feed of the same kind are to be avoided. The quantity and quality should be watched. Too much hay is the most common error made in the feeding of horses. The working horse in good condition should be fed but little on holidays. For the heavily pregnant mare, excessive feeding is injurious and especial care must be taken to prevent colic in such a mare. Diseases often associated with overfeeding are: azoturia, FOOD AND WATER 123 IjTiiphangitis, heaves, founder, garget, calf cholera, colic, etc. Feeding and watering should be so managed as to avoid dis- semination of disease, for example tuberculosis in cattle. Given a common feeding and watering trough, so that food or drink can be infected by a diseased animal, and then taken by another, the spread of disease may be rapid. Such a case is well illustrated by a common cement feed and water trough, where water comes in at one end of the trough and flows past the cattle to the lower end. One diseased animal at the upper end may contaminate the feed and water for many. PARASITIC DISEASES LECTUEE XXV PARASITISM Parasitism may be temporary or permanent, external or in- ternal. Parasites of domestic animals cause greater losses than is gen- erally realized. Every stockman should be informed concerning the most common and serious parasites, especially those of sheep. Parasitism may be temporary when only a portion of the para- site's life history is with one host; permanent, when its whole life history is with the same host; external or internal, when it affects the body surface or the internal organs. Sources and causes of parasitic diseases. — Parasites may be received into the digestive apparatus with food or drink, they may gain entrance through the respiratory tract, or broken skin; or there may be external infection by contact, as with lice or scab and mange mites. Nourishment. — Some parasites have mouth and digestive or- gans, e.g., roundworms of the intestines; others receive their nourishment by surface absorption or osmosis, e.g., tapeworms. Effect on health of host. — This depends on the organ or or- gans invaded, the rapidity of multiplication, the amount of nutrition used by parasite, and the amount of irritation caused. Intestinal parasites cause trouble by obstruction, by irritating and abstracting blood from the mucous membrane, by mechani- cal irritation, and by using nutrition. Hence, we have symp- toms of indigestion, colic, and unthrift. Liver parasites cause jaundice and general anemia. Lung and bronchial parasites cause bronchitis or pneumonia. Parasites in the hlood vessels cause disease of the vessel walls, and may indirectly cause obstructions and colic. Parasites in the hraim are more rare, and usually fatal. Parasites in muscidar tissue may cause little disturbance to the animal host, but be very serious to human health ; e.g., pig measles and trichina. 124 PARASITISM 125 General treatment. — Medical treatment must be siu-h as will destroy or remove the parasites. Medicines may aid in remov- ing parasites by suffocating them, by poisoning them, or by caus- tic or irritating chemical effect on the parasites. Many para- sites disappear at a certain stage by means of their own activity and habits; e.g., ticks, bots in horses, grubs in backs of cattle, •and grubs in the nasal passages and head cavities of sheep. It is well to remember also that many parasites, bots in the horse's stomach for instance, can resist stronger medicines than the organs or tissues they invade. Practical suggestions. — Parasitism would l)e impossible if everything that comes in contact with the animal body were free from parasites. Saddles, harness, blankets, posts, and fences are the usual agents which spread Texas itch or mange among horses; intestinal worms generally gain entrance in the egg or immature form, with the food or drinking water. Parasitic diseases may often be prevented by forethought and wise management. Intestinal parasites of sheep, like stomach worms, module disease, tapeworms, etc., may be largely prevented by change of grazing ground — pasture, meadow, stubble, millet, sorghum, rape, etc. Serious trouble from lice in winter should be prevented by proper treatment in the fall, while the weather is still warm enough for vigorous treatment by dipping or w^ashing. In many cases, the parasite requires two hosts, living its im- mature stage in one host, and its mature stage in another. Cer- tain immature tape worms which cause losses in sheep, use the dog for their mature form host. Unnecessary association of dogs and sheep on feeding ground is therefore unwise. Ponds, wells which receive surface drainage, sluggish streams and marshes, shoukl thei-efore be regarded with suspicion. Sound animals should not be allowed in sheds, yards, or barns where animals diseased by external parasites, like lice or scab mites, have been, until such structures have been disinfected. Intestinal worms w^hich appear in the manure of horses should be destroyed with boiling water, — not merely crushed and thrown aw^ay. External Parasites Lice. — These are wingless insects classified into two general groups, biting lice and sucking lice. Each of these general 126 VETERINARY STUDIES groups is subdivided into various families and species. As a rule they are specific, i.e., a certain species of louse is parasitic only on a certain species of bird or animal. In size, they vary greatly from mere specks to the giant hog louse which may be 1/5 of an inch long. Lice infect especially certain portions of the body surface of each animal, e.g., for cattle, the back ; for hogs, back of the ears, for poultry, the fluff and under the wings; for young chickens, the top of the head. Reproduction. — Lice reproduce by eggs (nits) glued to hairs or feathers. The eggs are very light in color and oval in shape. Treatment. — (1) Bathe the affected parts with corrosive sublimate in vinegar, 15 grains to the pint; or (2) tobacco water, prepared by steeping for an hour 2 ounces of tobacco to each quart of water; or (3) Professor Riley's kerosene emulsion made by mixing kerosene 2 gallons, soft soap one half pound, water 1 gallon. Dissolve the soap in water and add kerosene slowly while the water is still boiling. Churn 10 minutes Fig. 42.— Cattle ^^^^^ ^^^' ^^^®' dilute by adding 8 times its Louse. Female. bulk of water. This is cheap, harmless, and^ H aematopinus satisfactoiy. eurysternus. Yqy cattle, control lice by dipping or other thorough treatment in the fall before cold weather. Use any good coal tar dip 2 to 3 per cent and repeat in about 10 days. Any treatment for lice should usually be repeated several times at intervals of 10 to 20 days, depend- ing on season, the shorter interval for warmer weather. It is usually advisable to whitewash stalls and sheds. All harboring litter should be removed and burned. Brushes, combs, etc., must also be treated. Clipping is a great aid in the treatment of external parasitism. In fact, it is difficult to treat sheep successfully for either lice, sheep tick, or scab without shear- ing. Water solutions and oils are usually inadvisable in cold weather. For treating cattle, horses, and young stock in cold weather, dust frequently into the hair along neck, back, and rump, either Persian insect powder or powdered sabadilla seed and sulphur equal parts, A little kerosene oil on a brush and PARASITISM 127 used frequently, is safe and helpful if done with reasonable cau- tion. Volatile substances, especially wood alcohol, are effective, dry rapidly, are moderate in cost, and are safe in cold weather, when reasonably used. They are more effective, also, than a powder. Powdered sodium tluorid is effective for biting lice but not for sucking lice. For poultry use whitewash in abundance, and plenty of fine, air-slaked lime dusted into the nests and on the floor. It is a good plan to throw this lime against the wall, so that it will float in the air and then gradually settle down into crevices and over the poultry. Or kerosene may be sprayed over the walls and ceiling and the perches frequently washed with it. Kero- sene is cheap, can be rapidly applied, and is very effective. Constant access to dust bath of dust or sifted ashes, air-slaked lime, sulphur, and Persian insect powder, should be given and the poultry house should be kept dry. Flies. — At times flies prove a serious nuisance for domestic animals, particularly horses and cattle. Various preparations have been tried at different experiment stations with fairly sat- isfactory results. No. 1. — Was tested and reported as satisfactory by the Nebraska Experiment Station: Oil of wood tar 1 part; neutral oil (a petroleum product) 4 parts. Mix and shake thoroughly. A very light application of this should be made by brush or spray. It is occasionally necessary to sponge off the hair with a cloth, using a little of the neutral oil on account of a little gum which collects with repeated application. The following (Jensen) is probably still better: Dissolve 1 pound naphthaline in about V/o gallons crude oil, applying just sufficient heat to effect solution. Add to this 1 gallon of fish oil. In a separate vessel, dissolve about 21/2 pounds of common laun- dry soap in about 5 gallons of water. When the soap solution is complete, mix it with the oils and naphthaline, put it into an old churn and work it thoroughly together, adding gradually sufficient water to make the product measure 10 gal- lons. Apply daily or twice a week as needed with brush or spray. Sheep tick (Melophagus ovinus). — This is not a true tick but a wingless fly. The young larvae are attached at birth to the wool fibers. The pupa stage last from three to six weeks, after which maturity is reached. It is a permanent parasite, i.e. the 128 VETERINARY STUDIES Fig. 43. — Sheep Tick and Enlarged Proboscis. entire life history is passed on the sheep host. The mature tick pierces the skiu in order to suck blood, thus causing serious irritation and unthrift. The treatment commonly used is coal tar dip, 2 or 3 per cent applied after shearing. The wool must be stored where the dipped sheep cannot become reinfected from it. Dipping should be repeated in from twenty to forty days depending on the weather. Lambs must be protected during shearing time, otherwise the ticks will leave the older sheep and go to the lambs. Sheds, pens, etc., must be cleaned and disinfected a.s for lice. Ticks. — True ticks are temporary parasites, com- monly found in brush and tall grass. Life History. — The j'oung female crawls up on brush or grass or weeds and waits for some animal to come along and brush her off. She soon attaches to the skin, gorges with blood, and drops off. After a few days, she begins laj'ing several thousand eggs and dies soon afterward. The eggs hatch in 15 to 20 days if conditions are favorable. Treatment. — Any safe oily preparation may be used to de- stroy the common ticks. (See Texas Fever for dipping.) Ringworm. — This disease appears most commonly on the heads and necks of cattle, especially calves; but man and all domestic animals are also subject to it. It is caused by a vegetable para- site (Trichopliyton) growing in the skin, somewhat like mil- dew in a grape leaf. This disease appears in the form of round, raised, and bald patches, especially on the heads and necks of calves during the winter. The patches are scaly or crusty, an inch or two across; the hairs stand erect, then split and break. There are usually several such patches close together. Ring- worm spreads readily by inoculation. It is not especially seri- ous; but it is disagreeable. A good method of treating ringworm is to use scrubbing Melophagus ovinus. Properly a sheep louse. PARASITISM 129 brush, soap, and warm water; then apply every other day 10 per cent carbolic acid in glycerin or tincture of iodin and glacial acetic acid in equal parts. Care must be taken not to get this into the eyes. LECTUEE XXVI SHEEP SCAB Sheep scab is a result of irritation of the skin, caused by mites, minute animal parasites that puncture the skin from the surface or burrow tunnels in it. There are three common types of these mites and three types of the disease which they cause. One variety of mites produces body scab, another head scab, and a third foot scab. Body scab is the most common, the others are relatively unimportant. Mites are permanent parasites, their entire life history being spent on one host ; they multiply with enormous rapidity. Body Scab Body scab is caused by mites (Psoroptes) which have power of free movement upon the surface. It is the most common and serious type of scab. This type spreads most rapidly over the individual body, and also rapidly through the flock and from flock to flock. General history. — This disease is likely to become serious before being noticed by the owner. The parasites which cause this type of the disease do not tunnel into the skin, but cause intense irritation, especially when the sheep are warm. The owner will usuallj^ remember, after he has become aware that body scab exists in his flock, that his sheep have seemed uneasy and that they have been rubbing and biting themselves occa- sionally for some time. After the disease is under way, the parasites live beneath the crusts, and constantly migrate outward, while the skin slowly heals in the center. The fleece of scabby sheep is usually rough, and the wool matted in places and easily rubbed ofi'. The para- sites which cause this form of the disease confine their work almost exclusively to parts of the body where the wool is long and thick. 130 SHEEP SCAB 131 How spread. — This form of the disease spreads rapidly through the Hock ; because of the location of parasites upon the body of the sheep, and because of the freely moving habits of the parasites. As a rule, the disease spreads most rapidly in autumn and winter, because the wool is then long and thick, furnishing favorable conditions for the parasites, and because the sheep are kept in closer contact at these seasons. The dis- ease makes more rapid progress then and is much more fatal Fig. 44. — A Plain Case of Sheep Scab. with the weaker sheep. These parasites may be transferred from one sheep to another in a great variety of ways ; for instance, tags of wool may be rubbed off and dropped almost anywhere. Diseased sheep infect posts and fences by rubbing against them, also the parasites escape from one sheep to another Avhile the sheep are in close contact in yards and sheds. A loaned buck is liable to bring back scab. Open pastures and yards usually become safe again after two months. Indoor pens, sheds, etc., once infected, may not be safe in less than a year without radical cleaning and dis- infection. Foot Scab The disease caused by foot scab mites (Chorioptes) appears on the feet and limbs. The diseased area extends very slowly, 132 VETERINARY STUDIES but may eventually reach the body. This form of scab also spreads very slowly from one animal to another. Sheep which are infected with it are apt to be almost constantly stamping and pawing. Local treatment, — Any of the sheep dips recommended for body scab may be used to treat this form of the disease. A 10 per cent solution of the creolin is simple, safe, and easily applied on small areas. Male. Fig. 45. — Sheep Scab Mites. Psoroptes, male (Cur- tice). Body scab. Sarcoptes (Lugger). Head seab. J'°fms)e. Sarcoptes (Pevtit). Head scab. Any dip or ointment that will kill the parasites is sufficient early in the disease, but it may be necessary in old cases to soften the scabs by a little oil or a thorough scrubbing with brush and hot soapsuds. Head Scab The mites (Sarcoptes) which cause head scab burrow tunnels in the skin. The eggs are deposited in these tunnels and there hatched. This type of scab may appear on almost any portion of the head. It may slowly invade the neck and other portions of the body where the wool is short ; but it is less common and less serious than body scab. General Prevention Prevention is more important than treatment in any case where it can be secured, because it is surer, it is cheaper, and is usually much easier to administer than treatment. Spread of scab. — Whether the scab spreads rapidly over the body or not depends to some extent upon the thriftiness or SHEEP SCAB 133 unthriftiness of the individual animal. When sheep are fat and the wool is well supplied with yolk, this disease spreads more slowly, and is much less serious. The infection is frequently made when one sheep rubs against posts or fences where scabby sheep have previously rubbed. In the latter case, the mites are first transferred from the diseased sheep to the post, and then from the post to the healthy sheep. In other cases, the mites are transferred when a diseased sheep rubs against a healthy one. Precautions. — Pens, sheds, and yards which have held scabby slieej) should be thoroughly cleaned and disinfected; and, unless tiie disinfection is very thorough, they should not be used for sheep until at least four weeks have elapsed. It is supposed that a hard rain will practically disinfect ground surfaces, but not fences and posts. Fields and pastures in which scabby sheep have been held should not be used again until after an interval of several weeks, and preferably not until after a heavy rain. General Symptoms History and diagnosis. — At the point of infection there oc- curs the puncture ; then a little pimple, soft on top, which rup- tures, a little fluid escaping. Dust and other foreign matter collect in this fluid, the initial scab is started, and the diseased area spreads. Affected sheep are usually uneasy and are seen scratching against posts, rubbing against other sheep, and even biting the itching surface. The irritation is most noticeable when the sheep are heated, as by exercise, or confined in a close room. At first the wool hangs in tags, the sheep begin to pull out por- tions of the wool with the mouth, and the skin becomes bare in patches which increase as the mites spread, irritating and in- flaming the skin. To determine the presence of the mites, scrape off some of the scab and a little of the healthy skin near the border of the scab. Place these scrapings upon some smooth black surface in warm sunshine, and examine with a good hand lens. The mites may then be seen as minute white bodies about 1/50 of an inch long. They are most certainly recognized when they are seen to move. It is sometimes difficult to distinguish otherwise betw'een the mites and particles of liglit-colored dust or epithelial scales from the skin surface. One is more apt to 134 VETERINARY STUDIES find the mites where the skin is greasy and glistening, and not where the skin is dry and dull. It should be borne in mind when examining a case of head scab that the mites which cause this disease burrow beneath the surface of the skin, so that it is necessary to scrape deeper than for ordinary body scab. Possible mistakes. — It is well to bear in mind, also, that other conditions may be mistaken for sheep scab, particularly dis- orders of the skin produced by other external parasites, such as lice and sheep ticks. These are easily seen and they do not cause any marked local lesion. Skin thickening is quite char- acteristic of scab, but not in the case of ticks or lice. In the so-called "wild fire" of sheep in northwestern states, the skin is red, but not thickened and hardened as in scab. Occasionally we have outbreaks of skin disease among sheep which on super- ficial examination resemble scab rather closely. These outbreaks, however, are due to the awns of a wild grass {Stipea sparta). These spearlike bodies gradually work their way through the wool into the skin, causing inflammation of the skin and con- siderable irritation. Treatment Suggestions. — Treatent is comparatively easy where there are but few sheep, but it is more difficult with large flocks. The size of the tank, material to be used, and method of dipping must depend upon the number of sheep, and the accessibility and expense of different materials. The dipping, as a rule, should not be done immediately after shearing. It is better to wait a week or ten days. Some good may be accomplished without shearing if the wool is parted by hand and care taken to get the medicine down to the skin, but it is the usual experience that dipping unshorn sheep is much less satisfactory. The entire flock must be dipped, those that are apparently sound as well as those that are diseased. And the owner must bear in mind that after shearing, the wool may be a source of danger, and that it should be so kept and handled as to avoid the possibility of reinfection. Dipping is effective only when it is thoroughly done and properly repeated. Lime and .sulphur, coal tar dips, tobacco and arsenic are the various ingredients that are commonly used in dipping for scab. The (luaiitity of dip required per sheep SHEEP SCAB 135 varies from two to four gallons, according to the number of sheep dipped and the material used. Less dip is needed for shorn than for unshorn sheep. It is a good rule to use any dip at about 100 degrees F. Dip- ping should be repeated in 10 days, and in some cases it may be necessary to give even a third dipping after a second inter- val of 10 days. For thorough work the entire flock should be shorn, then 8 or 10 days later dipped and confined for another 8 to 10 days in a place where there have been no scabby sheep for at least two months. At the close of this period of 8 to 10 days, the flock should be redipped and placed again where there is no danger of infection. Dips. — Several of the patent dips give excellent results, but these are usually more expensive than others and are objection- able, inasmuch as we do not know their composition. The fol- lowing are perhaps as good as any: Lime-and-sulphur dip. — This is cheap, safe, and very effective. It has given good satisfaction when made and used according to directions. Make this dip in the following proportions : ordi- nary sulphur, 24 lbs. ; unslaked lime or hydrated lime — but not airslaked — 8 lbs. ; water, 100 gallons. The lime and sulphur are placed in a large kettle or other suitable container with enough water to slake the lime and form a paste. After the lime is thoroughly slaked 30 gallons of water is added and the mixture is boiled and stirred for 3 hours. Add water to make up to the original 30 gallons, and allow the solution to settle overnight. The liquid should then be so drawn off as to avoid stirring up the sediment. A spigot placed about 4 inches from the bottom of the barrel or tank works nicely. For use, add enough water to make a total of 100 gallons. The ooze or sediment is not to be used on the animal body, but makes a good disinfectant for fences, pens and other enclos- ures. Lime and sulphur cannot be relied on to kill sheep ticks. Tobacco and sulphur or coal-tar dips should be used when there are both ticks and scab. Coal-tar dips. — Certain dips of this class are now approved by the Federal Bureau of Animal Industry when used in official strength and directions followed. 136 VETERINARY STUDIES Practical suggestions. — Each sheep should be kept in the dip at least two minutes by the watch, and each sheep should go under entirely at least once. Three to five minutes are neces- sary for bad cases with heavy crusts. Heavily pregnant ew^es can be safel}' dipped if handled with care. Ewes, lambs, and bucks should be dipped in separate lots. It is not advisable usually to dip sheep that have recent wounds even if the wounds are small unless they are nearly healed. Al- ways water and feed well within three to five hours before dip- ping. Soft water makes the best dip. The solution should be from 40 to 48 inches deep, with an allowance made for each sheep to carry out in the wool, two quarts to two gallons, depend- ing on the wool. Drowning and other accidents can be avoided by watchful care. Lambs may be dipped at about one month old. In using any dip no matter if proprietary or homemade, fol- low directions exactly. It is not uncommon for stockmen to have unsatisfactory results from the use of well-recognized dips, usually because they try the dip a little weaker than the direc- tions call for, or because they were a little careless and hurried the sheep through the dipping vat too rapidly, or by returning the sheep after dipping to infected pastures or yards. For a small flock the portable galvanized vats are very con- venient. There should be at least one drainage pen with floor to carry the dip from the dripping sheep back to the vat. Two such pens are a great convenience. Disinfectwn. — All structures, sheds, pens, posts, etc., that may have been contaminated should be cleaned and well disinfected unless sheep can be kept away from them for a long period, as previously indicated. Any good dip should make also a good disinfectant for this use. In case a lime-and-sulphur dip is selected, then the "ooze" or sediment which will otherwise be discarded may be used. Plowing or burning over ground makes it safe. LECTURE XXVII MANGE Horse IMange Causes. — flange of horses, cattle, hogs and many other ani- mals is similar in cause, symptoms, and spread to sheep seal). Horses, like sheep, are subject to three forms of the disease. The most common form in the horse is due to the Sarcoptes, Avhich burrows and affects the head, neck, and body. Another form is due to Psoroptes "svhich moves freely and affects the surface. A third form is due to the Chorioptes, which lives on 1lie surface, moves but little, and affects feet and legs, usually below the knees and hocks. Sarcoptes scahei var. cqui is a common cause of horse mange. This is one of the smaller mites, practi- cally invisible to the unaided eye. These mites burrow tunnels into and under the skin. The eggs are laid and the young are hatched in these tunnels. On account of this tunneling habit, spread is slow at first and the disease difficult to cure in advanced cases. Spread of mange mites may be direct from horse to horse or indirect by way of the harness, saddle, blanket, currycomb, or a post, for example. Symptoms. — The disease usually appears first on the head or side of the neck, and the first symptoms are small pimples and itching. The skin loses hair, becoming thickened, roughened, and wrinkled. Affected horses are much more uneasy at night, particularly in a warm stable. Treatment. — It is usually necessary to repeat treatment at least once, and in bad cases, several times at intervals of ten 137 Fig. 46. — Mange Mite. The cause of one form of horse mange. Psoroptes com- munis equi. 138 VETERINARY STUDIES days. Treat all horses that have been exposed to infection, and watch closely for reappearance of the disease. If the horses are halter broken and conditions permit, clip the hair and burn it. Soften the scabs and crusts by a thor- ough application of soft soap well rubbed in over the affected surface. The soap is left on for two or three hours and then washed off. The scab should then be very easy to remove. Allow the skin to dry and apply one of the following treatments. Cattle Mange (Barn Itch) This is the same general disease as horse mange and sheep scab. Mange causes serious trouble and losses in range cattle and is occasionally a source of serious trouble among farm herds. Breeding herds seem most apt to become affected on account of the most frequent opportunities for introducing it by the purchase of new breeding stock. This disease is rarely fatal in cattle that are well kept ; but is a source of financial losses by reason of unthrift. In farm herds it is a serious nuisance, and should not be neglected or ignored. Cause. — In cattle there are four types due to Sarcoptes, Psoroptes, and Chorioptes and Demodex. The Sarcoptes (burrowing) affect especially the inside of the thigh, root of tail, under surface of the neck and the brisket. The Chorioptes affect chiefly the tail and legs. This form is slow, local and much less important than Psoroptes. Demodex causes small lumps on neck and shoulders from millet to pea size. It is rare and practically incurable. The Psoroptes is most common. This form affects the general body surface, and spreads rapidly. It lives upon the surface of the body and can move about rather freely ; hence the disease spreads more rapidly than the common mange and is easier to cure. The skin irrita- tion and inflammation is due to punctures which the mites make in order to suck their nourishment. Symptoms. — Symptoms of cattle mange are similar in a gen- eral way to those shown in sheep scab and mange of horses. With cattle, the disease usually appears first on the neck or shoulder or near the tail, and from these places is spread over other portions of the body. The skin becomes bald, thickened and wrinkled and perhaps badly scratched and sore as a result of rubbing. MANGE 139 There may be very little to show for mange while the cattle are out on grass and doing well, although the mites are still present on the body. Fall, winter, and early spring are the seasons of greatest prevalence and annoyance. Treatment Cattle and horses may be either dipped ^ like sheep or treated with local applications according to the extent of the disease and number of animals affected. Dipping is more thorough and reliable. It may be done either in a long swimming tank, or the animals may be dipped one at a time in a dipping cage. All exposed animals and every portion of their body surface should be treated either by wash or dip. In case of dipping, all portions of the body should go under the dip at least once and the animal should be kept in the dip from two to four minutes. Treatment should be repeated in seven to ten days. If mange persists, after two good dippings, apply the treatment for Sarcoptic mange. In case of infected herds, dipping should be repeated twice each spring and fall until the disease is entirely removed. The dip should be quite warm, 100 to 105 degrees F. Stock must not be hungry or thirsty when dipped ; they should be fed and watered two to four hours before dipping. It is also important that stock be not heated, as by driving fast before dipping. Let them cool off first. After treatment, the stock should not be put back into in- fected yards, pens, or stables. Such enclosures should be either thoroughly disinfected or the stock should be kept out of them for a considerable period. Almost any oil when freely used on horses is liable to cause temporary loss of the hair. (a) Creosote, diluted with any non-irritating oil, 1 to 16, and iLsed by hand application for small areas, — never for areas covering more than one half of the body at one time. (&) Creosote, 1; oil of tar, 10; soft soap, 10; use like (a). (c) Lime and sidphiir dip is an old, thoroughly tried and reliable treatment which is cheap, effective, and safe. Direc- ' For detailed information, concerning dipping plants, see Nebraska Station Bulletin 74, North Dakota Station, Bulletin No. 61, or Bureau of Animal Industry, Bulletin 1017. 140 VETERINARY STUDIES tions should be followed closely as given under Sheep Scab Lect. XXVI. This dip is prepared as for sheep except that we use twelve pounds of lime instead of eight pounds. Always treat the apparently healthy skin to a considerable distance beyond the diseased border in case of small areas and local treatment. Prognosis. — The prospect of recovery is good in recent cases, but if the animal has been long and badly affected and the disease covers a considerable portion of the body, then the pros- pect is not encouraging. The Sarcoptic horse mange is much harder to cure than common body scab of cattle, and may re- quire three to five dippings at six to ten day periods, depend- ing on the weather. Disinfection. — All structures which may have become con- taminated should be thoroughly cleaned and disinfected. The ooze or sediment made in the preparation of lime sulphur dip will serve w^ell for this purpose, or a 6 per cent solution of any of the better coal-tar disinfectants may serve the same purpose. LECTURE XXVIII INTERNAL PARASITES INIany kinds of internal parasites seriously affect the various classes of stock. The few selected illustrations used here for the horse and sheep can give only o'eiieral information on th;^ subject. Space does not permit of detailed information con- cerning even those parasites selected for discussion. Losses in sheep from parasites, internal and external, are especially im- portant, and, as a rule, they are jireventable. Bots. — The common hot of the horse's stomach is the larva form of the horse gadfly or bot fly, Gastrophiliis intcsiinalis (equi). This fly is commonly observed buzzing around horses in the summer and early fall. It is about the size of a common honey ^^ bee. The bot fly reproduces by ^^ oval, light yellow eggs, which are ^^ attached by the adult fly to hairs W^ about the neck, breast, and fore- ^^ rjpj-f^g Fig. 47. — Horse Bot Fly and In due time, the eggs hatch and the small larva or bots escape. „„,,•,, e,^„^. L^rva in the third Some are licked off, burrow into the stage, mucous membrane of the lips for a few days, then escape and make their way to the stomach where they firmly attach themselves to the lining by small hooks. They remain thus in the stomach about 10 months, f nally passing off with manure. The next, or pupal stage, lasts from four to six weeks, and is passed in manure or in the ground. After this stage the mature fly appears, ready for the next generation. Another species, Gastrophiliis nasalis, locates in the horse's nasal chamber. A third species Gastrophiliis hemorrJioidalis lo- cates in the rectum, and causing intense itching at times. These parasites may be removed by free rectal injections of 0.5 per cent creolin. Bots rarely do any serious harm, although they are very com- mon, ^ledical treatment by the use of carbon bisulphide (6 141 142 VETERINARY STUDIES drams in capsules) is quite satisfactory. No food should be allowed during twenty-four hours before treatment. Four to six hours after treatment an oil physic, such as raw linseed oil, should be given. It is usually advisable to have this treatment given by a veterinarian. Nematodes (round worms). — For pin worms {Oxyuris equi) which inhabit the rectums of horses, empty this organ by means Fig. 48. — Horse Bots and Bot Fly. (B. A. I.) The eggs are deposited on the hairs during the fall. They are taken off by the tongue ; hatch, and develop mainly in the stomach, into the bots (larvae). of w-arm water injections, and then u>se I/2 gallon of warm rectal injections of astringent and bitter medicine, like a very mild solution of copperas or 0.5 per cent creolin or a strong tea made of quassia chips. ^ Repeat once daily for two or three days and follow with an oily physic, e.g., one quart of raw lin- seed oil. Ascaris equi. — For the "long white worms" 6 to 12 inches long, affecting the small intestine of horses, the treatment must be vigorous and continued. Give a cathartic of 1 quart linseed oil. Feed little or no hay for 4 days. Fast 12 hours, then give 1 to 4 ounces of turpentine in from 1 pint to 1 quart of raw linseed oil on the 5th day, and ^ A large handful of quassia chips in two quarts of ■wuter. Steep 15 minutes and let stand overnight. INTERNAL PARASITES 143 repeat on the 6th. Beginning on the sixteenth day repeat this whole process, if the first treatment does not seem entirely effec- tive. Always use raw linseed oil. A second method of treatment is as follows : After giving the preparatory treatment described above, give tartar emetic, 1 to 3 drams depending on the size and the age of the animal, mix- ing the medicine with a small, damp feed of oats or grain. Repeat in 12 hours. Keep the horse quiet and empty. Strong yles. — These are also round worms (Nematodes). The horse is affected especially by four species. In general the mature worm inhabits the cecum and the colon. The eggs are deposited, then pass off with the manure and hatch. The embryo worms are taken in by the future host with water or feed. Some of the immature worms pass through the intes- tinal mucous membrane and into the blood vessels of the abdomi- nal organs — the intestines for instance, where they are likely to indirectly cause colic and serious disease of the bowel, by ob- structing circulation. The symptoms are variable and not diagnostic. There are evi- dences of intestinal irritation like diarrhea, recurrent colic, unthrift and variable appetite, usually lack of appetite. Treatment for the strongyle infection in horses is satisfactory if given in time. Best results are secured from oil of chcno- podium. The horse is allowed no feed for 36 hours, then is given about 4 drams of this oil in a quart of raw linseed oil. For the common round worms in hogs, no food is given to the hog for from 8 to 24 hours. Then when the hog is hungry and emjjty, he is given one to 3 teaspoonfuls of turpentine, accord- ing to size and age, diluted about ten times in skimmed milk or thin slop. This dose is repeated daily for several days, and then a physic is given. Oil of chenopodium, about 45 drops in 1 ounce of castor oil per IDO i)ounds weight, is also very effective — especially when properly repeated. Tapeworms or taenia (flatworms). — These are especially seri- ous in sheep, which are infested by several species. Three kinds are common to cattle, sheep and goats. The life history of tape- worms is vtM-y significant. Taenia are two-host parasites. They pass the larval stage in one host as bladder-like cysts, and their adult form in another species of host as a flat, ribbon-like body of many short segments. For example, the sheep disease known as gid is caused by the bladder worm larva of a tapeworm which 144 VETERINARY STUDIES is adult in the dog. A common adult tapeworm of the human, has its larval or cyst stage in the flesh of the hog, causing what is called "measly pork." The adult tapeworm constantly forms new segments back of the small head. These segments ma- ture while new segments are being added in front of them. The terminal segments, filled with eggs, separate and pass off with the manure, while the head remains attached to the mucous membrane and continues to produce new segments. The injury to the host may be great or slight depending on the location — usually in the intestine — and number of worms. The worms may impair intestinal (capacity and function by mere I)resence in large numbers. They may enter bile ducts and cause serious trouble. Some species have heads armed Avith hooks which irritate the intestine and thus im- pair digestion and absorption. They may produce and free to the Fig. 49. — A Common Tapeworm OF Sheep (Curtice.) Taenia expansa, 1, Hjead and neck; A, A, suckers; B, B, folds in neck; C, C, first segments. 2. Head and body, showing segments. A, head. intestinal contents, toxins or poi- sons. The cyst stage may seriously disturb the invaded host organ, e.g., the brain as in gid. Treatment ^ can be useful only when given before weakness begins. Preparation for treatment is most important. Allow no dry bulky food for several days. Fast 12 to 24 hours, depend- ing on age and previous feed. Then give 1 to 2 drams freshly ground areca nut in a small feed such as damp bran, or in a small quantity of thin sirup, so that each sheep gets its proper dose. Copper sulphate used as for stomach worms (see Lee- ture XXX) is also a satisfactory treatment, and may be used for both parasites at the same time. Follow this treatment in 3 or 4 hours by a physic. ^ For sheep. Dose varies greatly with age and weight. LECTURE XXIX NODULE DISEASE OF SHEEP General history. — The history of outbreaks is often as fol- lows: Sheep have access during the summer and fall to low pastures or pond or well water that receives drainage from a sheep yard or pasture. Perhaps the grass was short and the tloek was compelled to graze very close. During the winter the fiock becomes unthrifty; some individuals grow thinner and weaker and a number die. A dead sheep is opened and the intestines show on the surface a large number of nodules about the size of garden peas, Avhicli are most common on the large intestine. As soon as grass comes and the sheep are turned out they begin to do better, and the disease seems to disappear. Cause. — The disease is caused by a minute roundworm. Sheep are affected by two species but OcsopJiagostomum columhianum is the common species.^ The adult worms are about three quar- ters of an inch in length and inhabit the intestines. The imma- ture forms vary from one hundredth to one sixth of an inch in length, depending on development, and exist inside of the little nodules which constitute the most prominent features of the disease as seen on examination post mortem. There is some question concerning the life history, but the eggs are apparently laid by the adult female in the intestine and as eggs or embryos pass out with manure, hatch outside, and gain entrance as embryos. The embryo worms find their way through the internal lining of the intestine, and locate in the bowel wall.^ Here they give rise as foreign bodies to the little tumors or nodules, about the size of a pea, which nature throws around them, evidently in an attempt to fence them in. They cause irritation as foreign bodies, and this irritation will account for the little tumors which are found on the side of the * Cattle and hogs have each one species of nodule worm wliich does not affect sheep. In these the loss is unimportant. ^Diniock has found evidence which indicates that the eggs may be de- posited within the intestinal mucous membrane and there hatch the em- bryo worms. 145 146 VETERINARY STUDIES intestine ; i.e., the nodules. The contents of these nodules is usually chees}^, and greenish or yellowish in color. Later the young worms leave the nodules and mature in the intestinal canal. Some of the eggs and adult worms pass out with the manure, and thus infect the pastures and feed yards, ponds, or sluggish streams which receive their drainage. Fig. 50. — Nodule Disease. (M. H. E.) Intestines of sheep. Injury done. — The extent of injury to the individual sheep depends mainly upon the number of worms present, and the con- dition of the sheep as to vitality and resisting power. There may be something of an inflammation of the bowels while the young worms are passing through the lining of the intestine, but the main injury is that of starvation. So large a portion of the bowel is affected by the parasites when they are present in great number that there is not enough healthy tissue for ab- sorption of food material. It may be, also, that the worms ex- crete poisonous substances; or their presence may lead indi- rectly to the formation of poisonous materials which are ab- sorbed. A badly infested sheep may have plenty of good food NODULE DISEASE OF SHEEI 147 and yet be too weak to eat it, or if able to eat, he may still be starving- becanse the intestinal wall cannot take up the food that may be ready for absorption. Diagnosis. — This disease is rather common among farm sheep. There is diarrhea, debility, pallor of mucous membranes, and emaciation. Diagnosis can only be made certain by finding the characteristic nodules in an examination of the dead animal, for sheep infested with some other parasitic diseases show simi- lar symptoms and conditions during life. Treatment. — It is probable that but little can be accomplished by medical treatment, because the worms, during a large part of their life history, are walled up in these nodules and beyond the reach of any medical agent. It is possible that worm-destroying medicines, like those rec- ommended for stomach worms, if frequently repeated during the summer, might prove both curative and preventive, by kill- ing the adult worms, which live free in the intestine. Pasture infection may be destroyed by plowing and cropping one season. Dr. Dahymple and others have shown that lambs may suckle the diseased dams under certain conditions and usually remain free from infection. This is accomplished by what is known as the bare-lot method. Under this system lambs are not allowed access to any pasture that can possibly have been contaminated by the older sheep. The bare-lot method provides that ewes and lambs must be kept in a lot that is bare of any grass or weeds which sheep may eat. This lot must be rather smooth and must drain promptly, without standing pools after rain. No grazing for the older sheep is permitted, the flock being fed on soiling crops and what- ever gi'ain may be necessary. Fresh, clean water must be pro- vided. Food and water must be given in such a way that they cannot possibly be contaminated from the ground ; food that falls out of the racks must be raked up rather frequently. Ewe lambs to be kept in the flock should be raised with spe- cial care to avoid trouble the next season from chance infection tliat occurs to sucli lambs from the bare lot. By this metliod the lambs may run with the diseased ewes until weaning time with comparatively slight risk of infection. In dealing with a serious outbreak of this disease it should be remembered that infested flocks usually do fairly well during the summer and early fall montlos. If a flock is badly infested with nodule 148 VETERINARY STUDIES disease, it will generally prove good management to nurse the flock through until spring, then depend on getting the sheep into shape for market during the summer, and sell out for butcher stock in the early fall. Such sheep are entirely fit for food purposes when in good flesh. Prevention. — New sheep should be purchased from a flock that has been thrifty during two previous late winters and early springs, and they should be kept for two seasons on some other pasture than the one previously used on the infected farm. It will be better still if the flock can be kept part of the season on pasture and part of the season on plowed crops; e.g., rape, sorghum, field peas, or meadow land that has not recently been used for sheep pasture. The new flock must not be allowed to drink from any pond or sluggish stream that has received drain- age from the infested pasture or barnyard. With a view to preventing this and other parasitic diseases, the flock should not be kept too long on one pasture, but should be moved from pasture to pasture; and from pasture to stubble fields, cut-over meadow, rape, etc. Sluggish streams and ponds should always be regarded with suspicion. It is possible to practically rid a flock from the nodule disease by following this course of shifting the flock about for several years, plowing up pastures occasionally, and using plowed crops. The infectiousness of pastures has been shown by care- ful experiment in which infected sheep were placed on small pastures during a season and then during the next season sheep were kept on this same pasture which were previously free from nodule disease. Rapid infection of the second flock was secured in this way. The disease spreads from ewes to pasture and from pasture to lamb. LECTURE XXX STOMACH WORMS (SHEEP) The stomach -worm is an especially common and serious para- site of sheep, and this means much, for parasitic diseases of sheep are the serious ones. This ])arasite is very widespread especially in permanent grass pastures. It affects sheep of all ages and young cattle, but especially lambs. Older sheep showing no symp- toms are the ones usually to blame for spreading the disease. The parasite {Hoemonchus contor- tus) which causes this trouble is a small, threadlike worm, perhaps an inch in length and so slender that it must be looked for carefully or one is liable to miss it. The individual worms are somewhat twisted and are found in the fourth stomach. Fre- quently they are in motion. If they are present in great numbers, the stomach contents near the mucous membrane may seem to be fairly alive and s(iuirming. The Avorms vary from reddish to dirty white in color. Life history. — Tliis parasite is pres- ent in the stomach at all times of the 'ii;. .'a. Embryo of Ila'tnonclius contortus coiled on tip of grass blailo. Enlarged 100 times. (Ransom, B. A. 1., Circular 93.) year. The eggs are passed off in the feces, hatch in 14 to 24 hours in warm weather, and reach tlie ensheathed embi-yo stage in from ten days to two weeks when conditions of temperature and moisture are suit- able. Eggs and newly hatched emliryos are very sensitive to freezing or drying, and easily die under these conditions. En- sheathed embryos are wry resistant. We cannot depend on 149 ]50 VETERINARY STUDIES their natural destruction in much less than a year. They have been shown to be capable of infection after several months. When the atmosphere is moist, embryos leave the manure or earth and crawl up the moistened blades of grass or similar objects, climbing only while there is moisture. If now they are swallowed by a suitable host, the embryo continues develop- ment for about three weeks, at which time the females may begin to produce eggs. Symptoms. — There are no diagnostic symptoms by which this disease can be distinguished from other internal parasitic dis- eases of sheep. There is a gradually developing dullness, weak- ness, and unthrift. Lambs are affected more seriously than older sheep. These are usually unthrifty during the late sum- mer, and some die during the late summer and fall. The most common and evident symptoms are pallor, loss of flesh, and weakness. The appetite is variable; affected sheep are usually dull, listless, and often have unusual thirst and diarrhea. There frequently appear swellings under the jaw. To make a certain diagnosis it is usually necessary to ex- amine the carcass of sheep recently dead or kill a sick one for this purpose. Examine very carefully the fourth stomach. If this stomach is opened at the top and contents allowed to rest quietly, the stomach worms, if present in sufficient numbers to cause trouble, will be seen in quite active motion, wiggling about like tiny snakes. They may sometimes be found in very large numbers close to the lining membrane as slender reddish worms varying from one half to about one inch in length. If the fourth stomach be emptied and the worms are present in large numbers, some may be seen attached to the mucous mem- brane. Management of infected flocks. — An infected pasture may be safe after a year if there has been no use by sheep in the inter- val. Burning over a pasture is very efficient for the ground actually burned over. A pasture that has been plowed and cropped one season is usually safe. Freezing kills eggs and early stage embryos. In dealing with an infected flock, we may treat both the lambs and their mothers, beginning with the ewes early in the season before the lambs are old enough to treat. The death loss may thus be prevented and the lambs do much better. It should be clear that there is no way of rapidly eradicating stomach worms STOMACH WORMS (SHEEP) 151 from a diseased flock. The rational hope lies in reduction and gradual eradication. Low, wet pastures are to be avoided. Hillside pastures are much safer so far as internal parasites are concerned; and if possible permanent pastures for sheep should not be used on account of danger from many kinds of internal parasites. Fre- quent changes of grazing ground are desirable for any flock, and especially one infested with internal parasites. In case of stomach worms, the flock should move every two or three weeks on pastures, meadows, fields, sowed crops, etc. Medical treatment. — Sheep intended for medical treatment should have no feed during 12 to 24 hours before the medicine is given. No matter which treatment is to be given, it should be tried on a few sheep before treating a very large number. The Bureau of Animal Industry has done some careful ex- perimenting in this line, and recommends coal-tar creosote as a satisfactory treatment. This medicine is not expensive and is very easily obtained and prepared but variable in quality. It is important to insist upon getting coal-tar creosote. If reliable coal tar creosote can be secured give as a 1 per cent solution; that is, 1 ounce of the creosote to 99 ounces of water in doses proportioned to the age and size of the sheep. Lambs 4 months old take 2 to 4 ounces; older sheep take 3 to 5 ounces. If there is any reason to suspect the presence of worms in the intestines, then thymol should be added to the creosote treatment. The dose of thymol is from 30 to 100 grains. Each dose of thymol is to be added to the dose of creo- sote after the latter has been mixed and measured, and should then be given immediately. Only fresh crystallized thymol should be accepted, Bluestone (copper sulphate) has been accepted as one of the most satisfactory treatments for tliis trouble, but it needs to be given in carefully regulated doses. Best results are secured from repeated doses every 4 to 6 weeks, from spring till frost. This medicine may be made up as follows: Dissolve 1 pound (avoirdupois) of fresh powdered bluestone in 12 gallons of water. For this treatment the animal must be kept off feed from 20 to 24 hours. The dose for a lamb 6 months old is 40 CO.; sheep 12 months old, 60 c.c. (about 2 ounces) ; 18 months, 80 c.c.; 2 years 90 to 100 c.c. ; calves 2 to 3 months old take about 100 c.c. When the bluestone treatment is used, sheep 152 VETERINARY STUDIES should receive no water on the day that they are treated, either before or after treatment. For the first treatment of a badly infected flock, repeat once or even twice at ten-day intervals. Treatment is easily given with a metal dose syringe. Drenching sheep. — For giving medicine to sheep, a drenching tube should be used, or a metal dose syringe, or a long-necked bottle. A very satisfactory drenching tube may be easily made with an ordinary tin funnel, which is inserted into one end of a rubber hose about 3 feet long and about one half inch in diameter. A piece of brass or iron tubing 4 to 6 inches long is inserted into the other end of the tube. The metal tube is placed in the animal 's mouth between the back teeth ; the funnel end is held at a convenient height and medicine poured slowly into it. It is better to give the medicine when the sheep is standing on its feet, because actual experiment has demonstrated that while the animal is in this position more of the medicine goes directly to the fourth stomach, where it is needed. The head must not be raised too high — not higher than level face ; other- wise there is danger of passing medicine into the lungs. Prevention. — Sick animals must be killed, or removed from the flock and confined where there is no drainage tc the pas- ture or yard used by other sheep or cattle. Water should be taken from wells that do not receive surface drainage, from large lakes or from running streams, although stagnant pools are lorobably not so dangerous in this connection as is commonly supposed. The tank or trough should be high enough so that the water cannot possibly be contaminated from droppings. High and well-drained pasture is always safer than low pas- tures so far as internal parasites in general are concerned. In- fected pastures should be burned over thoroughly and regu- larly for the purpose of destroying eggs and young worms. It should be borne in mind that when animals are well fed and well nourished, they are better able to resist the invasion of any parasite. LECTURE XXXI VERMINOUS BRONCHITIS, NASAL GRUB, AND CATARRH Verminous Bronchitis Cause. — This is a disease of the bronchial tubes and lungs, caused by several species of minute roundworms. The worms are similar in different domestic animals, but each animal has its own species. They vary from about one to three inches in length and are white or reddish to brown in color. There is little danger of infection from one kind of domestic animal to another. Sheep, goats, cattle, and pigs are subject to this disease. Older animals may be aflfected, but frequently carry the parasite without evident injury. Life history. — The mature worms, eggs, and embryos are found in tlie bronchial tubes. Either eggs or embryos are de- posited in the bronchial tubes. Some may be coughed up, then swallowed and pass with the manure. Future hosts take in the embryos witli food or drink, usually grass. The young parasites then go to the lungs. Apparently, but the one host is necessary. Wet pastures appear to be favorable to the spread of this trouble. It is possible that the eggs or dried embryos may be inhaled directly with particles of dust. The parasitism remains long dormant, developing slowly. Embryos are very resistant and tenacious of life. Some species have been shown to sur- vive for months as embryos in water or moist earth. If dried at certain stages of development, the embryos may revive in moisture after a year, according to one good authority. Symptoms. — At first tlun-e is a bronchial catarrh ; later a clironic anemia and pallor, with progressive loss of flesh and strength and with sliortness of breath. There is a cough which at first Is rather harsli, and later very weak. The cough is worse when animals are excited and when they move around. Sometimes small balls composed mainly of worms may be coughed out and actually seen. Respiration is difficult and in 153 154 VETERINARY STUDIES some cases accompanied by wheezing. Calves are able to resist rather longer than sheep. On examination post mortem there may be found masses of minute threadlike worms in the trachea and bronchial tubes, with a considerable quantity of purulent and viscid liquid in the tubes. Some lobules of the lungs may show very marked pneumonia. There may also be tubercles resembling those of tuberculosis, near the surface of the lungs, and also throughout the lung substance. Treatment.— Treatment by injection of medicines directly into the trachea has been tried and recommended in some cases, but is very apt to prove unsatisfactory. Benzine has been tried and reported successful. Inject about one dram (1 teaspoonful) slowly into the trachea. Use an ordinary hypodermic syringe and inject directly through the side of the trachea between two rings. The sheep must be held flat on the side at the time of injection and for five minutes afterward with the head as low as possible. It would be wise to treat but a few sheep at first and note results. The most promising treatment at present is by chloroform. Inject one-half to three-fourths of a teaspoonful of chloroform into the nostrils with an ordinary medicine dropper. Hold the head up and close the nostrils for a while. It would be well to begin this treatment cautiously. This treatment should be repeated two or three times at inter- vals of three to five days. Calves should have the same treat- ment with proportionately larger doses. Prevention. — Change pastures often ; keep sheep upon forage crops and upon frequently changed pastures. Avoid ponds, and well water which receives drainage from pastures, feed lots or barn yards. Nasal Grub — Sheep (Grub in the Head) This is a very poor name for a disease, but is the only one commonly understood, and is used here for that reason. Cause. — This disease is caused by the larva? of a fly {Oestrus ovis). This larva inhabits the various cavities of the head which communicate with the nasal chambers. See figure 52. Life history. — The mature fly resembles the well known bot fly of the horse, is of a dirty yellow or grayish yellow color, and VERMINOUS BRONCHITIS, NASAL GRUB, CATARRH 155 appears in the middle of the day, from July to September. Sheep become excited when the tiy is around, and hold their noses to the ground or against each other, although the fly does not bite or sting. The young larva^ are deposited about the nos- trils of the sheep from whence they crawl up into the various cavities of the head, including the horn cores, and may even reach the brain substance. They mature in about nine or ten months and escape from the nose during the spring and early summer. They then pass through another stage before the adult Fig. 52. — Sheep Gadfly (CEstrus ovis). Commonly called "nasal grub." a, adult; b, larva; c. puparium. fly appears, which occurs in four to seven weeks from the time the grubs escape from the nose. Symptoms. — A few larvje may not cause any evident disturb- ance. When present in larger numbers, the parasites cause great irritation accompanied by a marked catarrhal discharge from the nostrils. The affected animals may refuse to eat well and even cough. The sheep sneeze, shake their heads, and rub their noses and faces against their feet or other objects; some- times there are attacks of vertigo, and the walk may be unsteady or irregular ; severe eases may develop con\'ulsions and die. The nasal mucous membrane becomes thickened and this, with the discharge, interferes with respiration. Such sheep are unthrifty on account of the constant annoyance. On examination post mortem, grubs are found in the various openings and chambers 156 VETERINAEY STUDIES of the head, and the mucous membrane lining these cavities is inflamed. Treatment. — ]\Iedical treatment under ordinary circumstances is not practical; but much of the trouble may be prevented. Before the sheep are turned out in the morning, their noses may be smeared with tar or with a mixture of tar, turpentine, and fish oil. They may be forced to take their salt through a large hole bored in a log or a plank, tar being smeared around the edges of the hole so that when the sheep take their salt, they get tar around the nose and mouth. Catarrh in Sheep Sheep catarrh. — A form of catarrh is so frequently associated with nasal grub that it seems best to insert a brief mention of nonparasitic catarrh in this connection. Simple catarrh in sheep is usually due to bacteria, after cold rains, imperfect ventilation, and damp quarters, or undue ex- posure after early shearing have made the sheep less resistant. In other words, it is a case of so called ' ' catching cold. ' ' Many other cases of catarrh are due to parasitic invasion of the nasal chambers and head sinuses. Symptoms. — The affected sheep are noticed to be sneezing and coughing with discharge from the nose and eyes. The nasal discharge is thin at first, gradually becoming thicker. Some cases become chronic, especially when the subjects are weak and unthrifty. The inflammation of the nasal mucous mem- brane may extend into the head sinuses, causing extensive col- lections of pus, and may also extend down the mucous mem- brane lining the trachea. Prevention. — Nonparasitic catarrh is to be prevented, first of all, by abundant ventilation. Sheep are very frequently housed too closely in winter ; the interior of the building becomes damp, and the conditions in general are unwholesome. Healthy sheep do not need much protection in the winter-time, so far as warmth is concerned. If they are well sheltered from cold rains, snows, and cold winds, they are most thrifty with abundant ventilation. Sheep that are shorn early in the spring need careful manage- ment for a time in order to prevent this catarrh, however. Treatment. — Sick animals must have shelter which is dry, reasonably warm, and well ventilated. They must be well fed. VERMINOUS BRONCHITIS, NASAL GRUB, CATARRH 157 Their medicinal treatment should consist mainly of tonics; for instance, a simple, bitter vegetable tonic, like gentian root, which may be given in a powdered form in the feed two or three times daily— about one dram per sheep. INFECTIOUS DISEASES LECTURE XXXII ACTINOMYCOSIS— OR LUMPY JAW This disease is commonly called lumpy jaw or big head. It is characterized by the development of peculiar enlargements containing pus pockets, usually around the head. The disease may also affect other external parts and internal organs. Cause. — The tumors and abscesses which characterize lumpy jaw have a common origin ; namely the presence and activity of a form of higher bacteria known as actinomyces {Actinomyces hovis) aided by various common pus producing bacteria. When the abscesses are opened, there is usually found in the interior, thick glairy pus containing minute grains, usually yellow and sometimes very abundant. These small grains may be bedded in the diseased soft tissues of the tumors. Seen under a micro- scope, these grains appear to be composed of radiating fila- ments with club-shaped extremities around the border of the mass. In artificial media it forms long, slender threads, often branching. As the fungus multiplies and spreads the tumor growths increase in size. The tumors are usually very firm on account of the large amount of connective tissue which they contain. The interior is somewhat honeycombed, and the pockets are filled with characteristic pus containing the granules of actinomyces. Animals affected are chiefly cattle, horses, and sheep. Relation to public health. — Human beings are evidently sus- ceptible to inoculation from this disease, but as the affected parts of diseased carcasses are not commonly used as articles of human food, and animal meats as a rule are cooked before being eaten, there is ordinarily slight danger for human beings. The gov- ernment meat inspection regulations pass carcasses which are but slightly and locally diseased, and condemn those which are extensively and generally diseased. Parts involved. — The external parts commonly affected are the bones of the upper and lower jaws, soft tissues between the two branches of the lower jaw, and tongue. This disease some- 158 ACTINOMYCOSIS— OR LUMPY JAW 159 times affects the lungs and other internal organs, and may be mistaken for tuberculosis. The lung symptoms, as seen on ex- amination post mortem, vary so much that it is rather difficult to describe them. Sometimes the lungs resemble those seen in ordinary bronchopneumonia. Considerable areas of the lung tissue may be changed to a gray mass, soft to the touch. In still other cases there are developed distinct abscesses with fluid contents. Pig. .53. — Actinomycosis — Lumpy Jaw. (M. II. K.) Note the enlarged jaw and the raw, granulating tissue exposed. This disease is usually of slow development. A small swell- ing appears somewhere about the head, perhaps under the tongue; or the bones of the face near the teeth begin to bulge slightly outward and the enlargements continue very slowly. The animal may remain thrifty for a long time, or indeed until the disease involves the teeth, tongue, or other organs and inter- feres directly with nutrition. Prevention. — There is so little known concerning the life his- tory of the parasite and the methods of infection that a study of prevention can be only partially satisfactory. It is generally agreed that animals develop lumpy jaw only after inoculation, 160 VETERINARY STUDIES i.e., when the germs find entrance throngh some cut or scratch in the skin ; throngh the mucous membrane of the mouth on account of diseased teeth; or through some abrasion of the Fig. 54. — Actinomycosis. (M. H. B.) Inferior maxilla of cow shown in Fig. 53. mucous membrane of the mouth, gullet, or stomach. It is also generally agreed that the parasite is usually taken in with the food. It is possible that this fungus may live through one stage of its development, and even multiply, upon the surface or in Fig. 55. — Actinomycosis. (M. U. E.) A badly diseased upper jaw. the tissues of some of the common fodder plants, particularly barley and rye. Direct inoculation from one animal to another usually fails to reproduce the disease. ACTINOMYCOSIS— OR LUMPY JAW 161 An animal with a discharging abscess about the head would of course infect food in mangers, feeding troughs, and grass in the pasture, thus ottering abundant opportunities for infection. Pastures wherein cases of lumpy jaw seem to develop rather commonly should be placed under cultivation for a time and animals with discharging abscesses confined or sent to market, it being conceded by all authorities that most of these carcasses killed under inspection are fit for food uses and should not be wasted by condemnation. Treatment. — There are several possible lines of treatment : surgical, caustic, and internal medication. Surgical treatment. — Removal by knife should be undertaken only by a trained veterinarian, on account of the large blood vessels and other important structures involved. Caustic. — Destruction of the tumor mass by caustics, arsenic paste, for example is satisfactory in suitable cases, where there is time for a slow cure and the case is not far advanced. This work should also be done by a trained veterinarian. Deep hypodermic injections of tincture of iodin or of Lugol's iodin give good results in some cases. This iodin treatment causes large swelling and violent inflammation, which seems to react unfavorably upon the actinomyces. Internal medication. — This treatment consists of tlie internal use of iodid of potash, given by tlie mouth either as a drench or in the drinking water. Lugol's iodin, by deep hypodermic in- jection into the tumor, may be combined with the internal treat- ment. Early eases may be treated in this way with a good prospect of success. The dose limit is about one fourth dram per one hundred pounds live weight. This dose is given once daily until the animal seems to get off feed and discharges freely from the eyes and nose, indicating a catarrhal disturbance of these mu- cous membranes. The skin will also become drv, wrinkled and scurfy. Such conditions indicate that the treatment should be discontinued for three or four days. During tliis period a mild cathartic of epsom salts about one pound to 1000 pounds live weight, should be dissolved in water and given as a drench. The iodid treatment may then be continued for another period of six to ten days, when it may be necessary to discontinue again and give another dose of ei)som salts. Treatment sliould be continued until the tumor is reduced to about one third of its 162 VETERINARY STUDIES original size. It may as well be discontinued if there are no favorable results in 4 or 5 weeks. The time required for successful treatment in suitable cases varies from four to seven weeks. It is not advisable to under- tjake the treatment of any case where there is evident bony enlargement, or where there is serious disease of the bony struc- ture, lodid treatment is liable to check milk flow and spoil the flavor of the milk. LECTURE XXXIII ANTHRAX ' One of the oldest diseases known to medical science and one which is almost world wide is anthrax. It afifects a wide range of subjects and is usually fatal. Animals affected. — All of the domestic farm animals are more or less susceptible to anthrax. The disease is transmissible, and very fatal to human beings, chiefly by inoculation, but it may be taken by means of food or water, or by the inhalation of dried spores. Cause. — Anthrax is caused by a microscopic rod-shaped or- ganism or germ, the Bacterium anthracis. The rod stage of the organism is found in living blood, ^^^ immediately after death, while the spore stage occurs outside of the body. •«««^^— — — •« The rod is more easily destroyed than fig. 56.— b a c t e r i u m is the spore. The spore may retain its (Bacillus)^Anthracis. vitality in surface soil, manure, in- The specific 'cause of an- fected foodstuffs, blood, hides, hair and thrax. w'ool of anthrax victims for long pe- riods, and be capable of causing fresh outbreaks. A contamin- ated pasture for example remains infectious for years. • The period of incubation is probably short. In experimental animals it varies from one to five days. No true toxin has been demonstrated for this virus; but B. anthracis may be present in the blood in such numbers as to block the capillaries. It also produces an enzyme which digests blood serum and destroys the red corpuscles. Modes of infection.— (1) Dried spores may be inhaled and so reach the general circulation by way of the capillaries of the lungs. Human beings following certain occupations, as wool sorting, mattress making, etc., obtain infection in this way more often than do the lower animals. ' This lecture contributed originally by Dr. W. H. Dalrymple, of Louisiana, and later revised by the author. 163 164 VETERINARY STUDIES (2) When infection is introduced by inoculation through the skin, there results the condition known as external anthrax, carbuncular disease, inoculation anthrax, or malignant pustule. This may be occasioned by insects, especially of the blood-suck- ing varieties, such as the various horse or gad flies; probably, also, by some varieties of the mosquito. The infection may come through wounds made by infected instruments or uten- sils; or by wounds coming in contact with virulent material. In the Lower IMississippi Valley the external form occurs very frequently, and some outbreaks extend over considerable terri- tory, among horses and mules, on account of the vast numbers of horseflies during the summer months. (3) Infection may occur through the digestive tract. This internal, or intestinal, form of anthrax is generally produced by taking the virus in contaminated food or water. Methods of introduction and spread. — Anthrax virus may be introduced by imported hides, hair, wool, etc., from foreign countries infected with anthrax. Fertilizing materials manu- factured from animals affected with the disease may be a source of infection, also running water may become contaminated and spread infection along its course. The refuse water from tan- neries has been known to disseminate infection from anthrax hides. Insects, after feeding upon infected blood and tissues, may carry the virus to healthy animals at a distance. Insects may probably, also, infect food materials in troughs and man- gers, by conveying virulent matter on their bodies and feet. Carrion birds, through the medium of their excrement or soiled feet, may infect pastures on which they alight. Carnivorous and omnivorous animals, as dogs and hogs, running at large, after feeding upon anthrax carcasses, may carry away viru- lent blood on their feet; and if these animals themselves die, they become fresh centers of the disease. Foodstuffs, as grass, cereal grains and their by-products, hay, etc., raised upon lands infected with anthrax spores, may carry those spores and spread the disease. Human beings coming in contact with virulent anthrax material, and having their clothes, shoes, hands, etc., soiled thereby, may spread the disease to animals. Neglect to properly dispose of anthrax carcasses is, perhaps, the factor most responsible for the continuance and spread of anthrax. Period of incubation.— The time that elapses between infee- ANTHRAX 165 tion and symptoms depends upon the method of infection and the amount of infective material introduced, and may range from a very few hours to several days. Symptoms. — In cj-ffnial or cuitincous anthrax, there is swell- ing at the point or points of inoculation (carbuncle or ma- lignant pustule), with considerable local edema (localized watery swelling). This is painful and hot at first, but afterwards be- comes cold and insensitive. If inoculations have been made by insects, the carbuncles may be numerous over different parts of the body. Tlie swellings extend in the connective tissue along the course of the lymjili vessels and glands. This form is seen most frequently in tlie thinner-skinned herbivora — horse, mule, etc. In internal anthrax, we have various types of the disease, espe- cially a pulmonary or thoracic and an abdominal form. Symp- toms vary accordingl.y and diagnosis even by an experienced veterinarian is not always easy. Some cases, especially the first ones, die very suddenly. The illness may last from a very few hours to several days. In general there are : sudden seizure, great depression, and ])rostration ; rapid rise to high tempera- ture ; stupor ; muscular weakness and twitchings ; vertigo ; hur- ried respirations ; increased heart action ; visible mucous mem- branes are hemorrhagic, dark red or a bluish red color or ooz- ing l)lood ; sometimes the coloring matter of the blood appears in the urine. Such cases usually terminate fatally. External manifestations in the hog are usually confined to the throat ; and there are generally other symptoms of a specific fever present. As a rule, death takes place from asphyxia. The hog becomes infected from eating anthrax carcasses ; and the disease is most frequent in this animal during epizootics. Course of the disease. — In isolated cases, in limited outbreaks, and in tlie early stage of an outbreak, the course of the disease is usually very acute and rapid; Avhih", toward the termination of tlie outbreak, anthrax seems much less fatal, many of the affected animals recovering. Or, in other words, the virulence of the disease seems to become weakened toward the end of the outbreak, or the most susceptible animals die first and with acute cases. Examination post mortem. — On are-uunt of the danger to the operator, and the risk of spreading the disease, through the infectivity of the blood, post-mortem examination of an anthrax 166 VETERINARY STUDIES carcass is dangerous. It is therefore recommended only under very unusual conditions, when undertaken by an expert fa- miliar with the danger incurred, and where possible spread of the virus can be controlled. Diagnosis. — In carcasses of animals dead from anthrax, there is very rapid decomposition and bloating. The blood is dark and does not clot. Exposure of the blood to air does not restore its normal red color. The spleen is greatly enlarged. There may be bloody discharge from rectum, bladder, nostrils, etc. Severe inflammation of various internal organs, with local hemorrhages, is common in acute cases. Local swellings under the skin are not tilled with gas, and do not crackle under pres- sure, as do those of blackleg. Diagnosis is safest and most reliable by microscopic examina- tion of a small quantity of blood from the extremities (ear of larger animals, or a foot of the smaller), verified by inoculation of laboratory animals with anthrax blood, and followed by microscopic examination of the blood of the inoculated animals. Treatment. — Ordinary medical treatment appears useless in most cases. Prevention. — Prevention by vaccination should be practiced annually in anthrax districts, or in sporadic outbreaks, as re- quired, and is very important. There is a small risk of loss from vaccination anthrax ; but the loss is less serious than risk from the disease. There should be cremation of carcasses ; very thorough dis- infection of premises (stables, sheds, yards, etc.) ; drainage and cultivation of infected lands ; destruction of horseflies, mosqui- toes, etc. ; drainage of pools and stagnant water where these insects breed or frequent ; and effective live-stock sanitary leg- islation. There are now three methods of vaccinating; (a) by single, reduced virus vaccine; (&) by serum with virus; (c) by double virus (reduced). The serum-virus method should be used for horses and sheep, and for cattle, when the disease has already appeared in the herd. The single virus is not usually advisable. The double virus vaccine should be used for cattle when there is serious risk of infection, but the actual disease has not yet appeared. Serum only should be given in affected herds, to animals of any kind showing fever and not in hopeless condition. LECTURE XXXIV SYMPTOMATIC ANTHRAX Symptomatic aiitlirax is also known as blacklcp', bl-ick quarter, eU'. It is a fatal, infections ami enzootie disease of thrifty yonngr eattle. It is ai)t to appear year after year on certain pastures oi- along certain valleys. Cattle more than two years of age are not usually affeetecl. Sheep and goats are subject to this disease, but cases are rare. Attack and recovery gives immunity. Cause. — A short spore-forming bacillus {Bacillus chauvoei) causes this disease. This bacillus produces spores and the spores are very resistant, being able to renuiin virulent in the soil for years — under favorable conditions. Infection usually occurs by inoculation, through the skin or mucous membrane; more com- monly through the former. So far as it is known, this disease is not contagions by mere association. The period of incubation is short — about 3 to 5 days. Authorities are not fully agreed but B. chauvoei is apparently a producer of a virulent toxin. Symptoms. — The symptoms are local, and general or consti- tutional. Local symptoms. — There is usually a pronounced swelling in- volving the front or liind quarter, and occasionally the loin, breast or throat. It does not extend below the hock or knee. This swelling is characterized by crepitation as one passes the hand over it, due to an accumulation of gas in the loose sub- cutaneous tissues. An incision inio the swelling reveals llie presence of dark, frothy blood, with ixM-uliar acetone odor. The swelling is not invariable. Some cases, especially those which appear at the beginning of the outbreak and die very suddenly, may not show the characteristic swelling. Constitutional symptoms. — The constitutional symptoms ai-e usually acute, and develop rapidly. The animal is dull and without appetite. It shows high fever and marked debility. The constitutional symptoms may last from one to three days, and the case usually terminates fatally. The fever may reach 167 168 VETERINARY STUDIES 106° or even 107° F. There is lameness in those cases which show local swellings of the front or hind qnarters. Some cases are mild and misleading and diagnosis is not always easy. The dnration of typical cases is from a few hours to several days. Examination post mortem. — Examination of the carcass re- veals a tnmor tilled with gas and dark, frothy blood with fetid odor. The spleen is normal, and blood from the general cir- culation is also apparently normal, clotting readily on expo- sure to air. In such features as normal spleen, normally clotting blood, and gas-tilled tumor, the disease differs from true anthrax. Carcasses decompose and bloat rapidly and dark frothy blood may ooze from the natural openings as in true anthrax. The muscles involved in the local lesions are very dark when first exposed to the air, and hemorrhagic conditions are common in the chest and abdominal cavities. Prevention. — As soon as the disease appears, cattle under two years of age should be promptly changed to another and pref- erably higher pasture. If the young cattle have been on dry food, their food then should be changed. Such feed may be safely given to horses however. Blackleg carcasses should be handled like those of anthrax, to avoid scattering the virus of a serious disease. Vaccination is now satisfactory and thoroughly practical. There are a number of commercial preparations on the market that are quite reliable. The federal Bureau of Animal Industry is supplying a blackleg vaccine, which is quite satisfactory. Method of vaccination depends upon the kind of preparation used. Directions usually accompany each shipment from any of the reliable makers. Vaccination The vaccine. — The Bureau or government vaccine consists of a brownish powder furnished in packets of ten and twenty-five doses each. It is made from the muscle of animals affected with blackleg, and is prepared by drying the muscle and grinding and heating it to a temperature which lowers the virulence of the bacilli, but does not destroy them. Preparation. — The needed outfit consists of a graduated hypo- dermic syringe of about 5 c.c. capacity: rather short, stout needles of good caliber, and sharp ; a small mortar and pestle ; SYMPTOMATIC ANTHRAX 169 absorbent cotton for filtering, and a measure graduated for cubic centimeters. All these must be sterilized by boiling, or otherwise, before using. The vaccine is i)repared for use by emptying a given number of doses into thv mortar, adding a few drops of boiled and cooled water, and thoroughly grinding. Then as many cubic centimeters of water, boiled and cooled, are added as there were doses of vaccine. This is well mixed, filtered in the funnel through loosely packed cotton, and the filtered liquid is used for the vaccination. The injection is made by hypo- dermic syringe on the side of the neck or back of the shoulder. Dose. — The dose is 1 c.c. for yearlings and somewhat less for younger animals, down to .5 c.c. for calves. Suggestions. — It is not usually necessary to vaccinate calves under six months nor over two years. If calves under six months are vaccinated, they may require revaccination next season. Vaccination should be given a few weeks before this trouble usualh' appears, as the disease tends to appear at ap- proximately the .s.ame time each year. Vaccination should not be given to calves that are weak from disease or ill health, nor at the same time with, or soon after, any surgical operation like castration. There should be an interval of at least ten days after the latter operation. Calves that are accustomed to being handled may be vaccinated standing in the stable. Those that are wild must usually be thrown or confined in a chute. There are several newer immunizing preparations now on the market: (1) Aggression, prepared by extracting juices from dis- eased tissue under pressure, filtering and preserving by phenol (carbolic acid) ; (2) filtrate, a filtrate from a laboratory artifi- cial culture of B. chauvai, and preserved by phenol; (3) anti- hlackleg serum, from the blood of horses that have had a series of weekly injections of blackleg virus in large doses. This serum seems to have some curative value early in the case. Treatment. — ^ledical treatment for this disease is not con- sidered satisfactory or. as a rule, worth while. Prevention by vaccination is easily applied, inexpensive, and usually satis- factory. LECTURE XXXV BACILLUS NECROPHORUS INFECTIONS Here we have a group of similar diseases, each due princi- pally to B. necrophorus. Included in this group are: foot-rot of sheep, foul foot in cattle, lip and leg ulceration of sheep, canker sore mouth in young pigs, and necrotic enteritis of older hogs. In each case, the characteristic lesion is a local inflam- mation with a marked tendency to local necrosis, for example, an ulcer or a diphtheritic membrane. Fig. 57. — Bacillus Necrophorus. (B. A. I.) Coccoid, bacillary and filamentous forms. Cause. — The principal cause of necrophorus infections is Bacillus necrophorus. A distinctive peculiarity of this bacillus is its tendency to destroy local tissue through its products. This bacillus is associated with filth. It is apparently a nor- mal inhabitant of the intestines of swine, and perhaps of other animals. Infection is therefore liable to come from manure or from contaminated soil, soil recently fertilized with hog ma- nure, for example. 170 BACILLUS NECROPHORUS INFECTIONS 171 Infection occurs in all these diseases by inoculation, throngli wounds of skin or mucous membranes, as when little pigs are teething-. The lesions produced de])end on the point of inocula- tion, age and species of the animal, the virulence of the infec- tion and the character of the associated bacteria. Losses are often serious, especially in lip and leg ulceration, canker sore mouth, and foot-rot. In dealing ^vith any of these diseases, it is of the utmost importance that one be on guard for the first case. Prompt treatment with early isolation checks or lessens their spread. Foot-Rot Foot-rot is a very old and familiar disease. It is often insidi- ous at first, the appetite appearing good, and the lameness slight ; but it must be taken seriously at the beginning, and treated promptly, lest it extend to the deeper structures and involve even the bone. Most outbreaks are infectious. Cause. — A large percent- age of these cases are caused by Bacillus necropJiorus;, which is commonly found in dirt and barn yard filth. General symptoms. — This disease usually affects the feet and produces lameness, slight and perhaps in one fore foot only at first, be- tween and above the claws. Later the lameness becomes severe. There is a dis- charge, with very offensive odor, and the hoof itself becomes rotten in places. Loose pieces are detached and the sole may be affected in the same way. The sensitive parts may l)e exposed in very severe eases with a development of profuse granulations. The skin above and between the hoofs is red, tender and swollen, and the toes are widely spread. The animal is lame and, of course, unthrifty. The discharge is at first fluid and fetid. After one or two weeks it becomes cheesy and foul, and seems to destroy the horn and skin which it touciies. In from twenty to thirty days the Fig. 58. — Foot-Rot op Sheep. A plain case. 172 VETERINARY STUDIES claw begins to separate ; there appears to be great pain ; tlie sheep travels on its knees. Several months after the beginning of the disease, the claws may drop off in improperly treated or neglected cases. Differential diagnosis. — It is necessary to distinguish between foot-rot and a very different disease which we know as "foot- and-mouth disease." Foot-rot begins in the skin between the claws or at the crown of the foot, and slowly involves the wall and sole. It then spreads both as to surface and depth, involv- ing the deeper structures of the foot. Foot-and-mouth disease may also begin with an inflammation of the skin between the claws or just above the hoofs. The skin becomes red, then small vesicles or blisters develop which rupture and later dry. In foot-and-mouth disease the whole hoof may loosen early at the crown, the inflammation involving especially the skin at the crown and sensitive parts under the wall and above the sole. In foot-rot the horn is diseased and separates in pieces. Foot- and-mouth disease affects several feet and perhaps the mouth and udder, also, — simultaneously. Foot rot usually affects one foot at first, and there is little or no fever in common cases, whereas in foot-and-mouth disease the fever is characteristic. Foot-rot develops slowly, the animals usually eating fairly well for some time. This is not the case with foot-and-mouth disease, Avhich spreads readily from sheep to cattle and swine. Foot-rot does not spread from one species to another. Treatment. — Clean thoroughly between the toes; pare away all diseased horn and remove the loosened pieces. The hoof, if grown out of shape, must be trimmed to normal proportion. Excessive granulations must be cut away or removed by actual cautery, and be repressed by astringent measures or pressure bandages. Pledgets of tow may be dipped in tar and applied over the granulations, so as to bring pressure at the right point. Patients so treated should be kept upon clean dry footing, and serious eases should be taken up and kept in the yard or in dry stc.bles. For astringent dressing, use tincture of iron, varying it from full strength to 1 to 4 dissolved in water. Four per cent carbolized tar makes a good application for cleansing and disinfecting and keeps out dirt. Medical treatment particularly the astringent should be very carefully applied, especially in the crevices and deeper recesses. It is frequently advisable to treat a whole flock in a general BACILLUS NECROPHORUS LNFLCTIONS 173 way. In that case the flock may be driven through a large pan containing a solution which is about four inches deep and the animals should be forced to remain in the pan for several minutes to insure thorough treatment. This solution should be made by dissolving copper sulphate in water in the proportion of one pound to a gallon of water, or use chlorid of lime solu- tion made by dissolving one pound of fresh chlorid of lime to three gallons of water. Separate the diseased from the apparently healthy. Treat the latter firs^t and move these to a clean place, e.g., new pas- ture. If any of these become lame, examine, and if found diseased, move them to the diseased flock. Repeat trough treat- ment several times for the sound flock at about two-day inter- vals. The diseased flock should have the same general treat- ment, repeated and continued as long as necessary. Trough treatment is satisfactory for both sound and average cases-, severe cases must have individual hand treatment. Prevention and management. — Diseased animals should be isolated from the healthy ones. Vigorous and repeated clean- ing and disinfections of the infected premises are necessary to the proper control and must begin early. Any good coal tar dip in 5 per cent strength will do. Either very wet or very dry pastures may be favorable to the development of the disease. Hoofs should be kept pared to reasonable proportions. Cases of foot-rot should not be neglected in the earlier stages, for they are much easier treated then. They may be infectious, and careful treatment and attention may prevent a general outbreak. Foul-Foot This is a disease of cattle resembling foot-rot of sheep and is apparently infectious, and due in most cases to Bacillus necro- phonis, which causes foot-rot. Treatment. — Trim off diseased horn freely. It is sometimes advisable in the early inflammatory stages to poultice with bran or oilmeal, using powdered charcoal (|uite freely in the poul- tice. For mild cases, white lotion may be used once daily. For more serious cases, use ten per cent solution of any good coal tar dip in glycerine once a day for two or three days, then reduce to a 5 per cent solution and use every other day for a week or two as necessary. 174 VETERINARY STUDIES After trimming and cleaning, some cases are well treated, by swabbing freely with lysol, or full strength sheep dip, or some other disinfectants, and then drying and applying a powder like scarlatone, or compound alum powder or calomel. It is sometimes advisable to use a roll of tar-soaked oakum, pressed well up between the toes, and held in place by a tar bandage around the foot. Where new tissue seems to grow too rapidly, it may be repressed by means of small pads of oakum or tow, soaked with tar and bandaged firmly over the part that needs checking. For astringent effect upon the granulations, tincture chlorid of iron, full strength or diluted as indicated to one fourth with water, may be used. Four per cent carbolic acid in tar is very useful, especially as it tends to keep out dirt and foreign matter. Lip-and-Leg Ulceration In this disease of sheep we again have local necrosis as the chief characteristic. This disorder may occur in conneccion with foot-rot. Symptoms. — The chief symptom of this trouble is the ulcers upon the skin most commonly of the legs, or upon the mouth parts, especially lips and muzzle. The ulcers have dry crusts with a granulating surface beneath. They may invade the mucous membrane of the mouth or nostril, or even of the eye. There is often a considerable slough and an offensive odor. Some cases are slight and chronic ; others, more severe. Treatment. — Scrape off the dead and the spongy tissue, then apply to the diseased area either zinc chlorid or silver nitrate, 10 per cent in water, and repeat three times a Aveek, or second, use an ointment of vaseline or lard, one hundred ; sulphur, 10 ; any good dip, five. Under good treatment prognosis is favorable. Canker Sore Mouth (Stomatitis) Canker sore mouth is also due to B. necraphorus, affects young pigs as a rule and older shoats occasionally. It is a troublesome, difficult disease to manage after there has been a general spread of the virus. Ground surfaces, floors, bellies of brood sows, etc., soon become contaminated with the infection. Many cases occur during the teething of young pigs. BACILLUS NECROPHORUS INFECTIONS 175 Calves have a similar trouble (calf diphtheria) due to the same virus and characterized by patches of diphtheritic mem- brane in the mouth, nose, larynx, and even the trachea. The necrotic areas in calves are much larger than in pigs. Symptoms. — Canker sore mouth is easily recognized by the small ulcers Avhich arc most common in the mouth or on the Fig. 59. — Lip-and-Leg Ulceration. {B. A. I.) Produced by artificial infection with Bacillus necrophorus. skin near the mouth. They may invade the nose and adjacent cavities, and the trachea, and even extend to the intestines. Prevention and management. — Keep brood sows and pigs away from the foot-rot of cattle and sheep and from what may be necrotic enteritis in other hogs. Avoid old pens and yards. In case of outbreak, only the most thorough cleaning and re- peated disinfection will suffice. When the season permits, it may be necessary to move sows and litters repeatedly to fresh grounds, and in some cases, it may pay to clean and disinfect the sow's belly before the pigs are allowed to nurse. 176 VETERINARY STUDIES Treatment. — Both the affected and the suspected pigs should be dipped to the ears two or three times a day for several days in some good coal tar dip of 5 per cent strength. In case of valuable pigs the individual ulcers may be cleaned and treated with 20 per cent silver nitrate, applied by a very small cotton swab. Necrotic Enteritis Necrotic enteritis is an infectious inflammation of the bowels of older hogs, due to B. necrophorus. It is sometimes mistaken for hog cholera and is often a complication of that disease. Symptoms. — Diagnosis in the living animals is difficult and uncertain. It may involve any portion of the mucous membrane of the digestive tube. Autopsy shows the typical local necrosis involving this mem- brane, — typical ulcers and larger patches of diphtheritic mem- brane covered with yellowish, cheesy material. There may be hemorrhages on the mucous membrane of the intestine, kidneys and other organs, resembling the hemorrhages of hog cholera. However necrotic enteritis is usually a slow disease and high fever is not characteristic as in hog cholera. Treatment. — Present methods of treating necrotic enteritis are very unsatisfactory. There is as yet nothing to be positively recommended. ]\Iany cases are undoubtedly complications of hog cholera. In ease of doubt, use hog cholera serum. Prevention and management. — Infection occurs by inocula- tion; therefore, avoid feed and feeding conditions favorable to this virus and liable to produce the abrasion necessary to infec- tions. The smallest scratch is sufficient for inoculation. Various intestinal parasites may undoubtedly injure the in- testinal mucosa, and permit infections. Treatment for the worms is therefore required as a preventive of this form of enteritis. LECTURE XXXVI FOOT-AND-MOUTH DISEASE Foot-and-mouth disease is a very contagious disease, chiefly of ruminant animals and swine, but horses and other animals are susceptible to it. Some outbreaks are much more virulent than others. ^Nlany cases are so mild as to be difficult to recog- nize; but whether they are virulent or mild they are always a serious matter for the owner of the stock, even though no animals die, and a very serious matter for the public because of extreme ease and rapidity of spread, the great difficulty and expense of eradication and actual money losses incurred. Sev- eral outbreaks have occurred in this country due to importa- tions, but they were eradicated and so far as known we have none in America at the present time. Cause. — The cause is a filterable and apparently invisible virus. Little is known about it except as to its disease produc- ing power. Infection. — Usually takes place by way of the digestive tube. Symptoms. — The symptoms are here given for cattle. Sheep and swine show, in general, similar symptoms. Foot-and-mouth disease develops in from three to five days after exposure. Affected cattle are first noticed to be sluggish. They shiver and later on are stiff and lame, and inclined to lie down by reason of the sore feet. There is a profuse flow of the saliva, with frequent swallowing motions and smacking of ,the lips. The peculiar lesions of the foot-and-mouth disease are vesicles or small blisters affecting the mouth and the skin above and between the hoofs, and over tiie udder and teats. The vesicles soon break, leaving raw surfaces which, as a rule, heal, but sometimes remain as rather chronic ulcers. The skin and superficial tissues around the hoofs become inflamed and swollen ; the stomach may also be involved ; weight is lost, and the milk flow is checked. Tt should be remembered that the symptoms vary greatly in virulence in different animals and 177 178 VETERINARY STUDIES different outbreaks, and one patient does not usually show all these symptoms. This disease is not ordinarily fatal, but it causes very serious losses in the checked milk flow, a prolonged unthrifty condi- tion, and seriously diseased feet. There is a marked fever, highest just before the eruption appears. Active symptoms of the disease last from eight to fourteen days. Disease of the skin around the hoofs often follows the mouth symptoms but the two may occur together. When the disease affects sheep and swine it is apt to involve especially the feet. Many cases are obscure and difficult of recognition. Others are severe and easily recognized. Some show no mouth symptoms and others no foot symptoms. There are several diseases that are easily mistaken for foot- and-mouth disease. (See Foot-rot.) Vesicular sio'rnatitis affects horses and cattle. The mouth symptoms are similar, but there are no foot or udder lesions and horses are not apt to have foot-and-mouth disease. Hogs and sheep have foot-and-mouth disease, but not vesicular stomatitis. Cow pox and sheep pox are of slow development and slow spread and show pustules after the vesicles. They rarely affect any parts except the udder and adjacent skin. Dissemination. — The infecting virus may be present in yards, stables, and on the food or feeding utensils on infected farms. Even a road over which diseased animals have passed may be infectious. This disease may be disseminated in an indefinite number of ways, and is recognized as one of the most easily scattered of the infectious diseases. The infectious material is apparently present in the discharge from the vesicles, in the saliva, milk, urine, manure, and perspiration. The infection is probably obtained through the respiratory or digestive organs, usually the latter. Prevention. — The prevention of this disease is simply the prevention of infection. Infected premises that have not been disinfected may remain infectious for an undetermined period. Until we have more positive information on this point, we may say that it will hardly be safe to risk exposure in less than a year unless the premises can be thoroughly disinfected. This disease spreads rapidly; it causes heavy losses, and is difficult to control after it has become widely scattered. Any FOOT-AND-MOUTH DISEASE 179 reasonable suspicion of its existence should be promptly re- ported to the local health ofifieer and every possible precaution taken to prevent spread. Treatment is not advised. It is usually advisable to kill and burn every diseased and exposed animal on the farm. The owner is then reimbursed by the state and government. LECTURE XXXVII HEMORRHAGIC SEPTICEMIA This group of diseases is important because of its many forms, and because medical treatment, so far as we know, is useless, and prevention is very uncertain. Those who have had a chance to study outbreaks have often been unable to trace any connection between one outbreak and another, or to trace a previous history for any given outbreak, except that local out- breaks on farms often follow the advent of stock from public stockyards. This disease is worthy of serious consideration, be- cause it is widespread and fatal. It appears suddenly at any season, and under all sorts of conditions ; a number of animals die, and the disease may disappear as suddenly as it came. Etiology. — The specific cause of this disease in cattle is appar- ently Bacillus hovisepticus. This is one of a group of very sim- ilar bacteria, which cause a group of similar diseases in different classes of stock, e.g., chicken cholera, hemorrhagic septicemia of cattle and of sheep, swine plague, septic pneumonia of calves, etc. All are characterized by hemorrhages in the tissues or under the skin, mucous membranes or serous membranes. In- fection may be caused by inoculation or through the respira- tory or alimentary mucous membranes. History and development. — The onset is usually sudden and unexpected, but in some outbreaks the onset is rather slow, and the cases are chronic. The period of incubation is prob- ably only a matter of a few days. Season and climatic condi- tions apparently have nothing to do with the prevalence, viru- lence or disappearance of this disease. The death rate is usually high. Symptoms. — Symptoms in the living animal are variable and uncertain. There are several fairly distinct types of the dis- ease in sheep and cattle, and symptoms vary accordingly : Some cases are marked by superficial swelling, severe inflammation, and small hemorrhages of the mucous membranes of the eye, 180 HEMORRHAGIC SEPTICEMIA 181 nose, or month. Other cases show symptoms of pneumonia with pleurisy — difficult, hurried, and joainful res])iration and fever. Calves frecjuently have this type of the disease. Some cases show abdominal pain, high fever, and abnormal movements ; and their attitudes indicate abdominal discomfort. In the writer's experience, the temperatures have been either normal or subnormal except where they rose rapidly just before death occurred. Local changes which correspond to the swellings of anthrax i 1 ■ \ ' ^ 1 ,1 k 1 ■ "' f ' 1 i i ■ p ^ .^^^^^ ^ H^^Bic^ ^^^H 2 ■ ^ ^Br^^ 1 ^p; :-l: ^^1 \d fcg^YI V ^^^^^^ ■ ■^'": 'V,:-' y^m lb B ■ Fig. 60. — HEiMOrrhagic Septicemia. {M. E. E.) Meningeal type. Cow stupid. Early stage. and sj^mptomatic anthrax are occasionally present; usually, however, tliev ai'e either limited or else wanting. The urine in some cases is scanty or l)h)od-stained, and this is also true of the l)owel discharges. Many cases of hemorrhagic septicemia, particularly those oc- curring in cattle, are of the meningeal, or nervous type. In this type of the disease, some cases early sliow an extreme nervous disturbance, while others develop such symptoms gradually. Cows whii'h iiave given a normal flow of milk in the morning may give practically none in the evening ; they are otherwise apparently normal. There may be no rise of temperature; and 182 VETERINARY STUDIES no evidence of pain or discomfort. Later when they attempt to walk, the gait is more or less irregular, resembling very much the gait of milk fever in its early stage. The symptoms^ dur- ing the first 2-1 to 36 hours are not marked, except that dull- ness, staggering gait, and cold extremities continue. The skin is harsh and lacking in sensation. Still later diarrhea often appears and nervous symptoms be- come more pronounced. The inability to walk naturally is Fig. 61. — Hemorrhagic Septicemia. (M. E. B.) Hemorrhages on costal pleura. continued ; the neck may be bent to one side, and the muscles, particularly of the face and neck, are spasmodically contracted. The sick animals may remain quiet, moving around very little; but the eyes have a wild expression, and there may be a nervous chewing motion with profuse flow of saliva. The temperatures are often normal or even subnormal. Later still there often appears intense nervous activity. The eyes become more wild and unnatural ; the grinding of the jaAvs grows more active and more constant; the convulsions of face * In case of young calves, these cases may be characterized by profound nervous disturbance very early in their histories. HEMORRHAGIC SEPTICEMIA 183 and neck muscles become more intense ; then gradually a period of intense restlessness and activity, and death. Examination post mortem. — The blood is apparently normal. Subcntaneous h emorrhages are common and vary greatly in size and intensity. In some cases they are large and the hemorrhagic condition is marked; in others they are minute, scattered, and few in number. They may appear almost anywhere in the sub- cutaneous tissues, or involve any of the internal organs; and they usually have sharply defined borders and are easily recognized as hem- orrhages. The spleen is not enlarged, but there may be hemor- rhages on its surface. The serous and mucous membranes frequently show small hemorrhagic areas, and the heart, especially its auricles, is often intensely hemorrhagic. Fig. 62.- -Hemorrhagic Septicemia. (M. H. R.) Hemorrhages on endocardium (in- ternal lining of tlie lieart). Differential Diagnosis It is very imi)ortant to distinguish between blackleg and hemorrhagic septicemia, because we have no demonstrated vac- cine or serum either preventive or curative and no medical treatment for hemorrhagic septicemia, whereas blackleg can be easily and cheaply i)revented by vaccination. In both diseases, death is lial)le to occur suddenly, but black- leg commonly affects only cattle under two years of age, and rarely young calves; wliereas hemorrhagic septicemia affects all ages indiscriminately. High temperatures are characteristic of blackleg, but not of hemorrhagic septicemia. Pronounced swell- ing of the front or hind ([uarter is characteristic of blackleg, although in some cases which die very suddenly there may be no 184 VETERINARY STUDIES noticeable swelling. Swellings of this kind are not characteristic of hemorrhagic septicemia, and when present are small. Blood taken from a blackleg swelling is dark and frothy, and has a peculiar odor. This does not apply to hemorrhagic septicemia. Fig. 63. — Hemorrhagic Septicemia. {M. H. R.) Hemorrhages (dark spots) on peritoneal surface of intestine. Blackleg carcasses bloat rapidly; the others do not. The stu- dents should compare hemorrhagic symptoms with anthrax also, and note the characteristic ditferences. LECTURE XXXVIII TEXAS OR TICK FEVERS This disease passes under a variety of names, such as acclima- tion fever, red water, liloody murrain, etc. Economic importance. — The seriousness of tick fever as a disease of cattle, and its bearing upon the southern cattle indus- try, was not realized until recent years. Causes. — It has been established that the disease is caused by a microscopic animal parasite, a protozoan {Piroplasma higemi- num) which attacks the red cor- puscles of the blood. Its multi- plication in the blood is rapid and its effects are destructive, in- volving especially the red blood corpuscles, which it destroys rajiidly. Transmission. — So far as known, the only natural means of transmitting the causative agent of this disease is the south- ern cattle tick {Margaropus an- nulatus).. Other species of ticks attack southern cattle, but this is the most common and is the only one responsible for transmission of the Texas Fever parasite. The ticks do not carry the pro- tozoan directly from one in- fected animal to another, but the female ticks develop on in- fected animals and tlien transmit the Piroi)lasma in some form to their progeny, which carry it to susceptible animals. Susceptibility. — Bovines alone seem susceptible to the dis- ease, although the tick, which carries the infection, occasionally infests horses and mules. Calves at birth as a rule have a high ^This lecture contributed by Dr. Tait Butler. 185 Fig. 64. Female engorged. annulatus (Riley). Tkxas Fever Tick. {Pettit.) Margaropus 186 VETERINARY STUDIES degree of immunity; but this immunity is gradually lost until at two years of age nearly all are highly susceptible to the disease. Cattle reared in the southern states on tiek-free pas- tures are as susceptible as those raised in the North. Period of incubation. — Tick fever usually develops in from eight to ten days after direct inoculation of a susceptible ani- mal with the blood of one infected, or that has acquired im- munity from a previous attack. When infection occurs in the natural way, a variable time elapses between exposure to tick infestation and the development of the disease. In some cases no evidences of the disease can be detected before from fifteen to thirty— or even ninety — days after exposure. However, a large percentage of cases develop within ten days after inocu- lation. Symptoms. — It is frequently stated that tick fever occurs in acute and chronic forms. The chronic form, however, often follows the acute, and appears months after the acute attack. These relapses or secondary attacks are not uncommon in the late fall and early winter. It is then difficult to distinguish them from ordinary debility from other causes except by the history of a previous attack or by an examination of the blood. Fever. — In the acute type of the disease an elevation of tem- perature is usually the first noticeable s^-mptom. A tempera- ture of 107 degrees or 108 degrees F. is not unusual, but when it reaches 105 degrees or 106 degrees, other symptoms usually become apparent. While there are considerable fluc- tuations, temperature generally remains high during five to seven days and may then drop suddenly to normal or below. Many animals die during the extremely high temperature, or, if the temperature falls, it is only as a prelude to death. The period of subnormal temperature is a dangerous one, and collapse should be fortified against ; otherwise an animal may succumb that might by proper treatment have been saved. Other symptoms. — The patient usually stands apart from the herd with head down and back arched, and in severe cases, or when death approaches, it may lie or fall down. The pulse and respiration are hurried. The urine may be highly colored as port wine, or almost black, especially in fatal cases and when near death. The red is coloring matter from the red corpuscles, w^hich are rapidly destroyed by the blood parasites (P. higemi- num). Other diseases producing bloody urine are rare among TEXAS OR TICK FEVER 187 cattle in this country. At first the bowels are constipated, hut later diarrhea is not uncommon. The mucous membranes are usually pale and sometimes slijjrhtly yellow. As death approaches and the symptoms become aggravated, the animal iLSually re- mains down. Occasional periods of excitement, or even convul- sions, may oceur. The ticks are usually to be found on the tender parts of the skin, such as between the hind legs, on the escutcheon, on the inside of the elbows, or on the brisket, which is most exposed. Since the disease may develop within ten days after ticks attack the animal, and this time is not sufficient for them to become larger than twice the size of a pinhead, it will be readily ap- preciated that to find the ticks is not always an easy matter, especially if they are not numerous. Post-mortem appearances. — Only in animals that die during an acute attack are the changes well marked, and of those just the more pronounced will be given. Other changes may be seen, but they are often slight, or else absent. Small ticks on the parts mentioned are very significant. The hlood is very thin and watery. The subcutaneous tissue may be slightly yellow and infiltrated with yellow-colored serum. In cases that succumb during the height of or just after the subsidence of the fever, the spleen is much enlarged and dark colored. When held up by one end, the contents of the cap- sule will tend to gravitate to the lower end. When cut it is found to be black, soft, and engorged with blood. The liver is enlarged, yellowish, and usually mottled in color, due to bile-injection. The gall bladder is distended wath bile, which is dark colored, thick and ropy. The kidneya are usually engorged and dark, and the bladder contains urine varying in color from slightly red to almost black. Treatment. — Treatment usually proves unsatisfactory, and the results scarcely justify the expense and trouble which it entails, except in very valuable animals, and in mild cases. The whole herd should be moved to non-infested ground and the ticks re- moved at least from the sick animals. During the first stages, when constipation is present, a purgative of about one pound of Epsom salts may be given. The salts sliould be followed by quinin 30 to 90 grains or an equivalent four times a day. If 188 VETERINARY STUDIES the temperature drops to normal, or below, stimulants should be used freely for a short time and be followed by iron and stryehnin until convalescence is established. When the first ease appears in a herd, all other animals that have been similarly exposed to tick infestation should be removed from further danger of such exposure, and thoroughly greased. Any cheap, nonirritating oil will do, but if it be one fourth kerosene, it will be more effective. AVhen a dipping vat is available, dipping in the arsenical solution, now used in tick eradication, is preferable to local treatment by oil. In this way an outbreak can usually be cut short, and the losses reduced very considerably. Prevention. — Immunity to tick fever in mature animals, so far as we now know, can only be secured' through an attack of the disease. Cattle raised on tick-infested pastures have been rendered immune by mild attacks of the disease while they were young and before they became fully susceptible. If it is true that immunity can only be secured through an attack of the disease, it follows that the only preventive is the exclusion or eradication of the tick. The ticks on any pasture or farm may be easily and quickly eradicated, and the farm maintained free from them. Hence, it is possible, if not yet practicable, to exterminate these para- sites over the entire South and maintain the country tick-free. Methods by AVhich Ticks May be Eradicated 1. Keep all cattle, mules, and horses out of the tick-infested pasture, lanes, and lots for one season, or, at least, after Sep- ber 1, and the ticks will be exterminated by May of the next spring. Or, 2. Divide the pasture by a fenee^ with* a rail or board tight on the ground or make a double fence — two fences 10 to 20 feet apart, — and keep all cattle, mules, and horses out of one half, this year after September 1 ; and out of the other half next year, and the work of eradicating the ticks will have been accom- plished. Or, 3. Dip all cattle in the standard arsenical solution once every 14 days from early spring until late fail. If this is done regu- larly and thoroughly the ticks will certainly be eradicated in one season. TEXAS OR TICK FEVER 189 Life history. — The methods just given are based on the fol- lowing facts concerning the life histoiy of this tick: the full- grown female tick drops off the cattle when she becomes en- gorged with blood. Her heavy body and small, short legs make crawling difficult, so she gets under the dry grass, or ''trash" close at hand. Within a few days she begins laying eggs, and lays from 1,500 to 2,500 during the next two weeks. In Avarm weather, under favorable conditions, these eggs hatch in two or three weeks. The period may be prolonged for eight weeks, or indeed, the hatching be prevented entirely, if the weather is sufficiently cold. The young ticks are very small when first hatched, being scarcely visible. They crawl up the grass, weeds, or small twigs, and there wait for the cattle to come along. If no cow, mule, or horse comes along for several months, these small ticks die from starvation, for they have no other known means of obtain- ing food for development. If the young ticks succeed in lodg- ing upon the skin of a cow, then in three or four weeks (and in cold weather much longer) they reach their full growth. The females, being engorged with blood, drop off and begin laying eggs as did their mothers. Neither old nor young ticks crawl far, hence a fence with a bottom rail or board on the ground will stop them, but wire fences do not always afford protection. Ticks do not crawl from one animal to another. Eggs laid during the cold weather of late fall and early winter do not hatcli, but go through the winter as eggs and hatch Avhen warm weather comes in the spring. All eggs laid before September 1 will probably hatch the same fall, and, therefore, the young ticks will be killed by the cold winter weather or starve to death before spring. Vaccination. — Not only does tick fever kill hundreds of thou- sands of dollars' worth of Southern cattle every year and depre- ciate the value of all those marketed from one fourth to one half cent per pound live weight, but it also offers the greatest exist- ing barrier to the improvement of the quality of cattle in the tick-infested area by rendering the imi)ortation of ])ure-bred animals for breeding purposes extra hazardous and expensive. For the purpose of conferring immunity on imported pure- bred or other cattle, a method of inoculation has been found practicable which very greatly reduces the otherwise heavy loss. 190 VETERINARY STUDIES Method.^ — The usual process consists in drawing blood from the jugular vein of an animal (not less than two years old) that was infested with ticks the preceding summer, and injecting it under the skin of the animal to be inoculated. This will pro- duce tick fever, usually in a mild form in from three to ten days. Not more than about three per cent will die from this inoculation if the subjects have been selected with proper care and are judiciously handled. About 5 to 7 per cent are im- perfectly immunized. Tlie dose varies from 1 to 3 c.c, depending on the age of the animal. Young cattle take the larger dose and older cattle the smaller. Cattle that do not show plain reaction, fever, de- pression, etc., should receive a second or even a third treat- ment, each dose being 50 per cent larger than the preceding and given at intervals of about 40 days. Young cattle less than one year old may be immunized by the use of young seed ticks but this method is not recommended where the blood-inoculaticn method is available and is not at all suitable for older cattle. Important conditions. — The animals should be between six and fifteen months old. Older cattle may be treated, but they are less conveniently handled and results are less satisfactory. The inoculating should preferably be done during December, January, or February, for tick fever is less severe in cold weather. All ticks should be kept off the inoculated cattle for about 60 days or until they have fully recovered from the inoculation fever. The inoculated cattle may then be protected for a time from gross tick infestation by having their legs and under parts of their bodies greased. A few ticks after the cattle have fully recovered from inoculation are useful as they reinforce the immunity. Inoculated animals on infected premises should be infested with the first crop of ticks appearing in the spring, for these are probably less virulent than those hatched in the fall, and therefore produce a milder type of disease. In the opinion of the writer the best method of introducing jiure-bred animals for improvement of the native stock is to ' See also Federal Bureau of Animal Industry and State Ag^rieultural Experiment Station bulletins on Texas Fever for additional details of vaccination. TEXAS OR TICK FEVER 191 import calves that are under four months of age and allow them to become immunized by tick infestation, as occurs with our native-born stock. But since the eradication of the ticks is now such an easy matter, the only practical method of dealing with tick fever is to prevent it by complete eradication of the ticks. LECTURE XXXIX TUBERCULOSIS The importance of the tuberculosis question is evidenced by its widespread prevalance, human susceptibility to bovine in- fection, great financial losses, direct and indirect, and its dis- turbance of breeder's plans. Prevalence. — Tuberculosis is one of the most widespread and universal diseases affecting either humanity or domestic ani- FiG. 65. — Bovine Tubkrculosis. (M. H. B.) A case showing plain symptoms of disease. Rare type. mals. It affects all of the domestic animals. Prevalence is greatest in the various classes of animals in the order named : cattle, hogs, horses and sheep. Chickens are also quite sus- ceptible to avian tubercle bacilli. Cause. — No fact in medicine is better established than that tuberculosis is caused by the Bacterium of tuberculosis. We cannot have tuberculosis without these germs, and it is prob- 192 TUBERCULOSIS 193 able that few people or domesticated animals can be placed un- der continued exposure to the germs without ultimately hav- ing: the disease. Predisposing conditions undoubtedly have much to do with its development — close confinement, lack of exercise, lack of ventilation and sunshine, and injndicious in- breeding, for instance, but these alone cannot cause it. Modes of entrance. — Germs of tuberculosis enter the body (1) through the lungs, with inhaled air; (2) through the Fig. 66. — Bovine Tuberculosis. (M. H. E.) A famous show steer, in prime "condition." Liable to be as badly dis- eased as the preceding. Stomach and intestines, with food and drink; (3) through broken skin or mucous membrane by inoculation; (4) by iiit'cc- tion in utero, i.e., before birth. The latter is of very rare occurrence and of small importance. Structures affected. — Tuberculosis may affect almost any tis- sue or organ of the body. Milk from tuberculous cows may be tuberculous; but the danger is especially great when the udders are affected. Statistics indicate that about one cow out of every four and six tenths (1:4.6) of all tuberculin reacting cows, give virulent milk. The extent of tissue diseased may vary from a small lesion 194 VETERINARY STUDIES in a small lymph gland to a general invasion of lungs, liver, kidneys, mesenteric glands, peritoneum, and pleura. Sjmiptoms. — These vary according to extent and location of the disease and are in general unreliable and indefinite. A few cases become thin and rough in appearance, have a chronic cough or chronic diarrhea, and show general debility. The great majority show no symptoms, and may appear to be in the finest possible physical condition. There are a great many Fig. 67. — Bovine Tuberculosis. (M. H. E.) A great variety of tubercles on the chest lining (costal pleura). Sternum below, broken ribs above. mild or latent cases, having but a small amount of diseased tissue, and the animals may live for many years in apparently good condition. On the other hand, they may succumb to a sudden development of the disease following any condition which produces debility. When the lu7igs are involved, there may be a loersistent cough, shortness of breath, pallor of visible mucous membranes, loss of flesh, and unusual sounds in the lungs. When intestines and mesenteric glands are affected, there may be chronic diarrhea with slow and persistent loss of con- dition. All these diagnostic symptoms may vary greatly and are often unreliable; e.g., a cow may be in good flesh, her hair TUBERCULOSIS 195 and eyes bright, and yet be extensively diseased, and die in a short time. Diagnosis.— The only reliable test, practical on a large scale in routine work, is tiiborcnlin, Avhich is very accurate but not infallible. There are three recognized tuberculin tests (see Lecture XL), all of which are useful. Medical treatment. — Medical Ircatinciit is not practical. It is advisable to destroy or isolate diseased animals at once. Very Fig. 68. — Bovine Tuberculosis. {M. U. E.) Tubercles on the great mesentery. valuable animals may be kept in isolation and used for breed- ing purposes with good results when considerable added expense and work are justified. Prevention. — Stockmen should breed and manage with a view- to increasing physical vigor. Bear in mind that an animal may have a fine physical appearance and yd be easily sus- ceptible to disease, if not actual 1\ diseased and a spreader. The practice of keeping cattle almost continuously in the stable does not harmonize with phun teachings of physiology, and the results must sooner or later l)e disastrous. The great law of animal life, that use begets strength and idleness begets 196 VETERINARY STUDIES disease, applies to lungs as well as to muscles, and must always hold true. Domestic animals cannot remain generation after generation healthy and vigorous without a reasonable amount of ■ exercise, sunshine, and fresh air. Nature's laws cannot be violated without paying an inevitable penalty. It is unwise to buy cattle for breeding purposes without knowing that they are free from tuberculosis and this implies first of all dealing with an honest breeder. Tuberculin tests of cattle from an unreliable breeder or jobber are of little value. All sires — this is especially true of cattle — should have abun- dant exercise in open yards or on treadmills, or be driven or worked. Ventilation must be thorough, and barns should be constructed with a view to allowing the entrance of abundant sunshine. Sunshine kills germs. The student must not gather from this statement that a herd may not be badly diseased in an ideal stable if tuber- culosis spreaders are put into it, nor that good sanitary condi- tions will clean up a diseased herd. There is abundant proof to the contrary. Such stables are safer and spread of infectious disease must be slower than where conditions are bad. Summary. — Do not found a herd with tuberculous stock. Do not introduce the disease while trying to improve a herd. Do not allow suspicious animals in stable with healthy ones. Avoid close confinement. Allow plenty of fresh air, exercise, and sunshine to breeding stock. All breeding cattle should be bought under tuberculin test, from a sound herd and a reliable breeder. Do not buy even on test from a tuberculous herd, or from a herd that has recently been badly affected. Disposition of tuberculous cattle. — Abundant experiments have demonstrated that healthy calves can be raised from tuber- culous cows, and from tuberculous sires. In case of unusual value or breeding, it is sometimes practical to free a herd from tuberculosis by breeding out the disease, instead of by immedi- ately killing all diseased animals. Animals which the owner does not think it advisable to keep in quarantine, at an increased expenditure of time and money, should be slaughtered. It is generally recognized that tuberculous animals should be slaugh- tered under inspection and many carcasses should be passed as fit for food purposes. Tuberculous cattle retained for breeding must be kept in a TUBERCULOSIS 197 separate stable — preferably on a different farm. They must not be watered at the same tank as healthy cattle, nor fed from common mangers. The danger m allowing tuberculous and non- tuberculous cattle to associate in the open air, is less than in a stable; but this disease undoubtedly spreads in the open air. Accredited herd plan. — Every stockman should know about the accredited herd plan. This is a common movement over the United States by which state and federal authorities are cooperating to free breeding herds from tuberculosis. Such herds are officially published as tuberculosis-free and the owner receives a certificate to this etfect from his state and the federal government. Requirements of the ])lan at the present time are, in general, two negative annual tests or three negative semiannual tests of the entire herd. The owner first signs an application and agreement ; his herd is tested (at public expense, in some states), until it becomes accredited. Thereafter it must be regularly tested each year by a private veterinarian at the owner's expense. This veterinarian must have passed a certain official examination. The advantages to the breeder of being on this list are obvi- ous: advertising and reputation, shipment interstate, advance compliance with laws and regulations concerning sale of pure- bred cattle for breeding purposes, and aiding in eradication of the disease at the fountain source of dissemination. There is, as a rule, more tuberculosis among pure bred cattle tlian among grades, and the general movement of the pure bred is from herd to herd whereas the grade moves from farm to killing floor. Fortunately, the prevalence of tuberculosis among pure-bred cattle is now being reduced and the near future may see the figures reversed as between pure-bred and grade cattle. The following figures will give the student an appreciation of the volume of this new movement for accredited herds. On Feb- ruary 1, 1922, there were 12,157 accredited herds in the United States; 104,467 herds which had had the first negative test; 18,956 on waiting lists and a total of nearly 143,449 under joint state and federal supervision, ^linnesota leads in clean herds at this date (February 1, 1922) with 1310 accredited herds and 2256 other herds with first clean test. LECTURE XL THE TUBERCULIN TEST FOR TUBERCULOSIS Tuberculin is usually seen in tablets or as a straw-colored fluid, slightly more viscid than water. The active ingredients of tuberculin are chemical products of the bacilli of tuberculosis. A certain broth is infected with the virus of tuberculosis, which is allowed to multijily and grow in this medium until it has become charged with the germ prod- ucts. The whole fluid is then heated to kill the bacteria and filtered through porcelain. Tuberculin should therefore be not only germ-free, but heated to a high temperature, and cannot be infectious. Effect on cattle. — Careful experiments have demonstrated that tuberculin has no important effect, favorable or otherwise, upon the health or milk flow of sound cattle ; and that the effect on tuberculous cattle is not objectionable. An experiment was conducted by the author at the Minnesota Experiment Station some years ago, which included 23 sound and 5 tuberculous cows, and compared the total milk flow and total butter fat of each animal and of the herd for the week prior to test with the week of test. In this experiment the cattle were given ordinary handling, neither very rough nor unusually gentle. There was a moderate decrease in the milk flow during the two days of test, not more than could be easily accounted for by unusual handling of the cattle and the presence of strangers. This decrease was almost made up during the succeeding five days. There was a slight increase of butter fat during the week of test. Both variations were easily within the limits of normal variation. The experiment with the five tuberculous cows produced about the same results, the difference being easily within the limits of normal variations, as neither the total milk flow nor total butter fat for the entire week was materially affected by the test. Similar experiments have been made elsewhere, the results agree- ing closely with this general statement. It is undoubtedly pos- 198 THE TUBERCULIN TEST FOR TUBERCULOSIS 199 sible for cattle to be so roughly handled during the test that the milk flow may be seriously affected ; but this cannot be charged to the tuberculin. In cases where serious results ac- company or follow tuberculin tests, the disturbance usually can be traced to some cause other than tuberculin. There are three methods of making tuberculin tests — the thermal or subcutaneous, the intradermal, and the ophthalmic. These may be used to good advantage in various combinations. Accuracy. — Averages of very large numbers of animals tested show tliat tuberculin has a high accuracy, but is not infallible. Advanced cases, recently tested animals, recently infected ani- mals, and certain latent and healed cases may fail to give plain reaction. These are all exceptions ; in general, tuberculous cattle react, and the tests are accurate enough to be thoroughly practical. Thermal or subcutaneous test. — Any number of animals up to 100 or so may be included in one test. These large numbers can be handled to advantage only by one who is thoroughly familiar with the test, who can use a number of thermometers, and has good assistants. The injection is usually made on the neck, on the flat of the rump, or beside the tail head. A veteri- nary hypodermic syringe, holding 10 to 30 c.c. and provided with several short and well sharpened needles is required. The syringe should be first sterilized and kept clean. The needle should be short, of fair size, and inserted by sharp push rather than a stab. Some cattle are inclined to kick. This can usually be prevented if an assistant gives the tail a vigorous pull sidewise at the right moment. Tivo periods. — The time of each test is divided into two periods: (A) before, and (B) after injection. During {A) the temperatures are taken e.g. at about 8 a.m., and then again at 2 and 4 p.m. The tuberculin is given by hypodermic injection at 10 P.M. During (B) the temperatures would be taken at 6, 8, 10, and 12 a.m., 2, 4, and sometimes (i and 8 p.m. The thermometer. — Self-registering veterinary thermometers are necessary for the thermal test and they slioukl be correct between 100° and 105° F. Any thermometer wliich varies one half degree or more from the records shown by several others should be discarded. Temperatures are taken by inserting tlie thermometer into the rectum or vagiiui, usually the former. If a number of cattle 200 VETERINARY STUMES are being tested and several thermometers are in use, the latter are secured to the tails for safety. This may be easily done by a wire clamp, rubber hand, and wire hook, or by shoestrings tied so as to give the tail a few inches of play. This permits the operator to use a large number of thermometers, and prevents them from falling to the Hoor and breaking. Dose. — The dose is about 1 c.c. or i^ dram Bureau tuberculin per 300 pounds live weight. Cautions. — Cattle must be kept under the same conditions as nearly as possible on both days; i.e., watered at the same hours, — immediately after a temperature never shortly before — and fed at the same hours on each day, given as nearly as possible the same amounts, and treated alike on the two days. There are many possibilities of error if the operator is not careful, accurate, and observing. The cattle must not be excited or worried in any way but kept as quiet as possible during the whole test. If the whole stable or any portion of it be much warmer on the second day than on the first, if any cattle are allowed to become thirsty or drink large quantities of cold water, or to go much beyond their feeding time, note should be made of the fact and this considered in making the diagnosis in doubtful cases. Drinking a large quantity of cold water may reduce the temperature one or two degrees at a critical time and spoil a low reaction in a diseased animal. Cattle that show high temperatures, above 103, during period (A) should ordinarily be released from test. Heavily pregnant cows may be tested if carefully handled and temperatures are normal. It is always possible that an animal may show normal temperature during (A) and then be feverish from causes not connected with the test, during (B). This rarely occurs, but the possibility must be borne in mind. Importance to hreeders. — The value of the test to breeders lies in the fact that it enables them to know whether their cattle are free from tuberculosis, to free their herds and put them on a sound and healthy basis in case they are diseased, and to buy safely. Diagnosis. — Diagnosis is made mainly upon the fever reaction. If during (B) the temperature rises about 2.5 degrees or more above the highest normal as shown by comparison of the (A) and (B) temperatures, and careless errors have been avoided, it is usually safe to diagnose tuberculosis, providing the (A) THE TUBERCULIN TEST FOR TUBERCULOSIS 201 temperatures are not unusually low. To an expert a rise of 1.5 or less may be a plain reaction in some cases and only suspicious or doubtful symptoms in others, so that the animal should be held for retest after 60 days. If the normal temperatures run 100° P. or less, we would not ordinarily condenni on a 2 degree rise. Experience and judgment are essential in this work. A first plain reaction should never be set aside for a subse- quent negative retest, as the first test is the best and each sub- sequent retest in general decreases in reliability. Obvious re- actors slioukl not as a rule be retested. The reaction. — The most typical reaction is one wherein there is gi'adual rise and gradual decline of temperature, but many plain reactions are not thus typical. Very abrupt changes in an animal's temperature should be verified with a different thermometer. One high temperature during (B), with the others normal or nearly so, may be only doubtful or suspicious, often it indicates an error in the record. Animals that react sometimes show diarrhea, local swelling at the site of injection, or shivering. The intradermal test. — This form of tuberculin test is a deli- cate operation requiring special skill and experience. It is made by injecting into the skin, usually in one of the folds under the root of the tail, a few drops of a special tuberculin with a short and very fine needle. Tuberculous animals exhibit reaction in the form of a per- sistent, local swelling at the site of injection. This should re- main 72 hours or more after the injection has been made. Healthy cattle may have a temporary swelling but are nearly or quite negative as a rule. The intradermal test in skillful hands is probably as accurate as the thermal test and it has the great advantage of greater speed with regard to the number of cattle that can be tested by an operator in a given time. It is therefore less expensive than the thermal test. The ophthalmic test. — This test is simpler in operation and interpretation than the thermal and intradermal tests; but it is less reliable for general work. It is made by putting special ophthalmic tuberculin in the eye. This ophthalmic tuberculin may be in either tablet or liquid form. A double treatment, sensitized ophthalmic test, gives most accurate results. By this method, the same eye is treated twice, with an interval of 3 to 202 VETERINARY STUDIES 5 days between treatments. Following the second treatment, observations begin at about the sixth hour and continue every two hours until about the twentieth hour unless plain reaction occurs in the meantime. Observations may also be made after the first eye treatment, if convenient. Tuberculous cattle react with a temporary inflammation of the eye structures; for example, hyperemia of the conjunctiva, pro- fuse flow of tears, pus in the eye — usually at the inner angle — , and sometimes by swelling of the lid. This reaction may be slight or very temporary, and the evidence, such as pus, may be easily wiped off or lost. Any two or all of these three tests may be used together in making a combination test. Any wise combination is necessarily somewhat more accurate than either of the single tests, because there are a few tuberculous cattle which at any given time will respond plainly to one test and not to another. Combination tests should be used, at least in badly affected herds and in herds of great value. A positive reaction by either test should usually condemn. A suspicious reaction by either test should at least isolate all animals giving such suspicious reactions. LECTURE XLI GLANDERS The words "glanders" and "farcy" refer to the same disease, the latter being commonly used for those forms where the skin and external parts are especially affected. This disease is seri- ous because it may be transmitted to human beings with usually fatal results, and because it results in great loss in horses. It is easily spread among susceptible animals. Obscure cases may be highly infections. Susceptible animals.— Glanders is practically confined to don- keys, mules and horses which are susceptible in the order named. Human beings, sheep, and goats are susceptible. Cattle are immune. Causes. — A minute rod-shaped germ (Bacillus mallei) is the direct and specific cause of glanders. Unsanitary conditions and everything wliich lessens the animal vigor may act as predis- posing causes. The disease is more severe and more rapidly fatal among animals which are crowded or overworked. Incubation. — The period of incubation varies greatly. Dif- ferent authors have given it variously from three to seven days in experimental work; but in natural cases it is usually about two weeks. Symptoms For our purpose, glanders will be divided into but two types: (a) Respiraiorjj glanders, with or without lung lesions; and (&) Farcy, affecting principally the skin and superficial connective tissue. Lung lesions may accompany either type. Acute and chronic cases of each form differ mainly in severity of symptoms and rapidity of development. Respiratory glanders. — Tliis type is characterized in general by the development of nodules, which change to ulcers on the mucous membrane of the respiratory ajiparatus; by a peculiar sticky discharge from the nose; and sometimes by chronic cough. Certain lymph glands between the branches of the lower jaw 203 204 VETERINARY STUDIES are affected in a peculiar way, becoming swollen, tender, then hardened and adherent. Acute cases. — In acute cases of respiratory glanders, small tubercles or nodules develop rapidly on the mucous membrane of the respiratory organs and soon change to small ulcers, which increase in size and even coalesce. Thus is developed the peculiar ulcer of glanders, with its dirty gray base and overhanging edges. Very large ulcers and even ragged, gutterlike excava- tions may develop, partic- ularly on the nasal sep- tum. The ulcers may heal, leaving light-colored, more or less star-shaped scars. The fever may be severe in acute glanders of either type, the temperature ris- ing rapidly to 105 or even 107, and then be quite variable for a few days. There may be also per- sistent chills. There are also areas of lung inflammation and nodules in some eases. Oc- casionally there is an ap- parent recovery from the acute symptoms and then development of a chronic case. This condition applies to both types of glanders. Chronic cases. — If the disease be chronic, then in general the symptoms develop less rapidly and the disease is slower and milder. The chronic pulmonary form of glanders may be sus- pected when there is a mild, dry cough, especially if such cough be accompanied by debility and occurs in a stable where an obvious ease of glanders has been demonstrated. When the lungs are much affected in chronic cases of pulmonary glanders, the horse is apt to show symptoms of heaves, and on examination post mortem there are found numerous tubercles, usually show- ing, or easily felt, on the surface of the lungs. Fig. 69.— Glanders (Farcy). (M. H. B.) A recent case. Note the enlarged leg without farcy buds. GLANDERS 205 A horse may he affected with a mild, chronic form of the disease and remain in good flesh, he vigorous and apparently in the hest of health for years, showing no marked nasal discharge or farcy sores, and yet be very actively infectious to other horses. Chronic eases may show a chronic nasal discharge, nasal ulcers, and hardened, ad- herent maxillary glands and unthrift. Farcy. — In the farcy form of glanders the su- perficial connective tissues and Ij-mph vessels and glands are especially in- volved. In the acute farm, there is high temperature and local swellings. These swellings often occur on one or both hind legs. As the swellings abate, the characteristic nodules, or farcy buds, appear. The head may swell badly and farcy sores ap- pear later at irregular in- tervals and places. Farcy buds tend to heal slowly and leave scars as shown in Fig. 71. When farcy buds break, there is discharged a clear, viscid pus that is very characteristic. The specific symptoms of farcy may be summed up as the hud, the ulcer, the lymphatic cord, and the characteristic viscid, sticky discharge. In the chronic form we have similar histories and symptoms, but the latter are less obvious and develop less rapidly. Diagnosis. — A positive diagnosis on the clinical symptoms may be frequently made. P>nt there are a great many cases which cannot be so diagnosed with certainty. Some show indefinite symptoms and others show none. In such cases, we must rely upon mallein tests of which we now have three. Mullein tests. — The temperature test is conducted as follows: 1^'iG. 70. — Glanders (Farcy j. {M. H. E.) An old case. Note enlarged leg with old farcy buds, healed. 206 VETERINARY STUDIES Temperatures are taken at, e.g., 10 a.m., 2 p.m. and 6 p.m. The mallein is then given by a hypodermic injection at about 10 P.M. On the following day temperatures are taken every two hours, beginning at 6 a.m. and continuing until 6 or 8 p.m. or even later if the temperature is rising and the reaction is indefi- nite. A rise of three degrees or more above the high normal to 104 or higher is diagnostic, and usually means glanders. Such a rise of temperature is spoken of as a reaction. Reacting animals usually show a prominent and painful swelling at the point of injection — an important con- sideration in the diagnosis. This test is being superseded by the newer and simpler tests. The second mallein test, the intrader- mal, is made by injecting a special mal- lein with a fine needle into the skin of the lower eyelid. The glandered horse reacts with an inflammation and per- sistent swelling at the point of injection. The third mallein test, the ophthalmic, is made by placing a special tuberculin in the eye. The glandered horse reacts by inflammation, and pus in the eye, usually at the inner angle. Mallein has revealed the rather serious fact that there are unquestionably many cases of glanders which are never recognized, some of them without doubt infectious. Prevention. — The common methods of spread must be borne in mind, and the fact be clearly realized that the germ which causes glanders is very easily disseminated. Some of the more common mediums of spreading it are drink- ing water, feed boxes and troughs, hitching racks and posts, and public water fountains, which should be abolished and re- placed by individual pails. Any means which serves to bring the virus, B. mallei, into direct contact with mucous membranes or with the broken skin may be sufficient to cause the disease. Pus from the farcy sores and the nasal discharge are very virulent. Prevention therefore consists in avoiding conditions which may bring the virus into contact Avith the mucous membranes Fig. 71.- (Farcy). -G- L A N D E R (M. E. B.) Farcy sears in the face. An old case. GLANDERS 207 or brokoii skin. It is never safe to purcliase from a stranpjer, a horse that lias nasal discharge or suspicious sores. Stories of having: caught cold or a "little distemper" may usually be sus- pected, under such circumstances. Treatment. — It is probable that some cases of glanders recover under favorable conditions without treatment, especially in the Northwest ; but the disease is dangerous and we have no means of knowing which cases have a reasonable probability of re- covery, for medical treatment by the use of drugs is not re- liable. For these reasons treatment of glanders is not justified. All cases should be reported to the proper health officers. Suggestions. — In many states it is wisely made a punishable ofifense to water a glandered horse at any public watering place, hitch it to a public rack or post, or place it in a public barn. All plain cases should be killed and all exposed horses and mules should be tested with mallein. Reactors should usually be killed, whether showing symptoms or not. In some states, OAvners receive state reimbursement for glan- dered horses killed by order of the state. LECTURE XLII HOG CHOLERA To be considered hog cholera, the disease must be infectious by pen exposure, and an attack followed by recovery must give immunity ; the blood from a diseased hog should be virulent and capable of reproducing the disease ; the living animal should show the symptoms later described ; and the carcass of the dead animal should show the symptoms given under {lutopsy. Variations in virulence. — Outbreaks of hog cholera vary greatly in virulence and symptoms. In some outbreaks the virulence is marked, and the hogs die quickly ; in others a ma- jority of the cases assume the chronic type, the hogs do not die so quickly, and the percentage of loss is not so gi-eat. Various gradations may appear between cases of the utmost virulence and those of the milder type. General symptoms. — Lack of appetite, fever, and thirst are early symptoms of hog cholera. The hair becomes harsh and dry, the eyes may be watery, and the gait becomes weak and irregular, with imperfect control of the hind legs. The skin around the flanks and fore legs and abdomen may become purple ; that of the ears frequently becomes much inflamed, and, if the hog lives for several days, may assume a scabby appear- ance. Sometimes the tips of the ears slough off. The sick hogs soon separate themselves from the rest of the herd, being dis- posed to hide in sheltered places, and are little inclined to move about. Chronic cases lose flesh rapidly and sometimes show extreme disturbance of the nervous system, exhibited in partial or complete paralysis of the hind parts, or extreme nervousness. The cough is usually short and hacking. Occasional constipa- tion appears among the earliest symptoms, but is usually not noticed ; later, diarrhea appears. In some of the very acute eases which appear at the beginning of an outbreak, the animals die very suddenly — sometimes before the owner realizes that they are sick. Later in the history of the disease, as it appears in a herd, the cases tend to assume the more chronic type. 208 HOG CHOLERA 209 At times quite large portions of skin and underlying muscu- lar tissue die and slough off, leaving large sores. These sores appear more commonly, perhaps, around the neck, head, and back than elsewhere. This is probably not due to the filterable virus but to secondary invaders. Farmers must bear in mind that symptoms vary greatly in different outbreaks, and avoid being led into tlie costly error of mistaking mild cholera for something else. It is not always easy even for an expert to diagnose cholera, and for this reason it is safer to assume that a questionable outbreak is cholera. Fig. 72. — Hog Cholera. (M. H. E.) Subcutaneous heinorihages resembling those of hemorrhagic septicaemia. Note the dark spots. Autopsy. — The skin on parts of the body where the hair is thin, like the Hanks and inside of the fore legs and thighs, may be deep red or purple. Hemorrhages may be usually found in the fatty tissue under the skin and on the internal organs. The lungs often show scattered and sharply defined areas which are dark in color, solid and much like liver. Or, there may be a severe general pneumonia with pleurisy. The lymph glands in the mesentery and elsewhere are deeply hyperemic or hem- orrhagic. When the large intestine is opened, dark spots, more or less bloodstained, or even clots of blood, may be seen upon tlic lining membrane when the disease is of a very acute type. The more chronic cases show peculiar and characteristic ulcers in the lin- ing membrane of the digestive tract, especially the large intes- tine, and they are usually more numerous near the cecum or blind pouch. These ulcers are irregular in outline, with yellow- ish or dark centers, and frequently appear as being raised above 210 VETERINARY STUDIES the surface. Small ulcers may occur in the back part of the mouth, in the gullet and stomach. Very small hemorrhages are found on the surface or through the deeper structure of the kidneys. Cause. — Hog cholera is a very infectious disease which has its origin in a living' virus. The virus particles are probably so small as to be invisible with our best microscopes and are capable of passing in some form through a laboratory germ filter. This is probably a complicated disease in most outbreaks. The filterable virus is evidently the principal and specific infec- tion. With this virus there is usually one or more secondary invaders. One of the secondary invaders may cause or con- tribute to the chronic lesions, ulcers of the digestive tract, for instance. Another may cause or contribute to the lung and pleura lesions. This accounts, in part, for the wide variations in symptoms and lesions. Infection usually occurs by way of the mouth, and the period of incubation is from 8 to 14 days. Simple conditions of keep and feed have much to do with making the animals susceptible, but food and surroundings cannot serve as the first cause of hog cholera. Predisposing factors must be given due consideration, but the most important things to remember are the sick hog and the living virus and that hog cholera never appears without the infection which may be easily carried from one place to another. If the hog is fed exclusively on corn diet and kept overfat ; or if it is kept shut up in dark, damp, and perhaps filthy pens, it will not be able to resist any disease as would the hog kept under more favorable conditions. But these are only contribut- ing factors. The laws of hygiene cannot be neglected without rendering any animals more susceptible to disease ; but no de- gree of ordinary vigor can give assurance of immunity to cholera. Fig. 73. — Hog Cholera. (M. H. B.) Hemorrhages (dark spots) on iliapliragin. Hemorrhages are char- acteristic. HOG CHOLERA 211 How scattered. — The virus of this disease may be carried from place to place in any way that very fine particles of heavy dust may be carried, e.g., by people, upon shoes, or by Avagons or stoe-k cars. Dogs are frequent carriers of the tlisease. Running streams and shallow lakes are serious factors in its spread. Bowel discharges are very important sources of infection^ and, if yards or pens drain into streams or lakes, water tlien becomes the carrier of infection. Hogs that have died of cholera are J^^^SP ■^ ^Bfii^^M^ ■^ ^^H • '^ ^ ^ 1 ^Sk^ ^^^^ N "1 K%..>^:- -< ^'^'^f%^. ^trifc ;iii>r,jJ ^■IrB^cBHHBm^^H I^SS^SkMsBm S^Bl^Bi^BSB^'v ^^^^Hi^^iSfls^^^^l ■ """^^^kS-^' ^^^^2^«r^1 ^^ V »- ' «4* J:*"" gy^T^'wi-S-^- ■^ ^i: 1^ 31 Fig. 74.— Hog Cholera. (M. H. E.) Large intestine; mucous membrane showing general distribution of typical ulcers. /, Ileum; C, caecum or blind pouch. sometimes thrown into streams or buried in sand near the edge of a stream or lake, thus infecting the water. Hog cholera virus may live many months; around strawstacks and old sheds under favorable conditions. When an outbreak appears.— In cas<> ihere is a suspicious disease among hogs, the matter should be reported promptly to health officers so that this first outbreak may be i)roniptl,y and rigidly (luarantined and the hogs vaccinated. If reliable serum for vaccination is not available then but one person should have the care of a herd of healthy hogs, and should not be allowed to go where there is possibility of carrying the infection on shoes, 212 VETERINAEY STUDIES for example. No member of the family should go to any farm where swine disease has appeared ; nor should any one from the farm where such sickness is present be allowed to walk about the yards of his neighbor. Dogs and other dangerous visitors should be kept away from the pens on uninfected farms by a temporary fence if necessary. Hogs should not be allowed access to small ponds or mudholes during the prevalence of any suspicious disease. Such ponds and mudholes become deadly centers of infection. Before a herd becomes infected, it may be desirable to divide it into three or four parts, if serum is not available, and sepa- rate these groups widely on different portions of the farm. The Fig. 75.— Hog Cholera. (M. H. E.) Ulcers in mucous membrane of large colon. Bowel split open. View of the interior. owner may then lose one group, or even two groups, and still save the others. If the weather is cool or wet, the herd should be given quar- ters as warm and dry as possible, because, under conditions of exposure, the mortality is apt to be very high. So far as we know now it is useless to spend money on medi- cines in the treatment of hog cholera and before giving credit to patent medicines, one should bear in mind that outbreaks often check suddenly without treatment. Experience demonstrates that it is desirable to luove the healthy animals away from the sick promptly, if serum is not available, and to place them in uninfected sheds, pens, or yards. It is also important to keep the pens, both where the sick and the healthy hogs are confined, thoroughly cleaned and frequently disinfected. For cleansing and disinfecting purposes, unslaked lime used freely is satisfactory, and easily applied. The better grades of coal-tar disinfectants are also satisfactory. HOG CHOLERA 213 Hog" cholera vaccination. — The Dorset-Niles serum is now freely available and is reliable when properly nsed. The method of produeing this serum is, in general, as follows: A hog that is immune by reason of having ])assed through the disease or having been vaeeinated is given a large quantity of virulent hog-eholera serum, llis own blood then develops a property which protects other hogs when it is injected under the skin or into muscular tissue. The serum of this hog's blood produces a prompt but temporary immunity. If the hog which has received such serum be given pen exposure with sick hogs, or an injection with a small quantity of virulent blood (simul- taneous vaccination), it then becomes rather permanently im- mune, for it has had the disease in a mild form and recovered. There are, therefore, two ways of vaccinating by the Dorset- Niles method : serum only, which gives prompt but temporary immunity; and simultaneous vaccination, which gives perma- nent immunity. The dose of serum varies according to the weight of the hog treated. Serum should be kept unopened and cool until used, and all precautions should be taken to insure clean work in vaccinating. There are other useful fields for this vaccine : Owners may wish to vaccinate valuable hogs in advance of any possible out- break, or exposure to disease at stock shows. Another and per- haps the most important field relates to outbreaks of the disease where vaccine can be used early iii an outbreak to prevent or lessen losses and thus protect surrounding herds and check the outbreaks. Common mistakes. — It is a mistake to bury hogs that have died of cholera when the carcasses can be burned, for burning is by far the most ef^cient means of destroying the germs of such diseases. If it is not convenient to burn the carcasses, they should be buried under at least four feet of earth and covered freely with fresh lime. It is a mistake, and frequently a serious one, for a farmer to ship in strange hogs from stockyards, and put these with stock hogs already on hand without vaccination or quarantine. The mere fact that the hogs came from an uninfected district is no argument to the contrary, for the car in which they were shipped may have recently carried hog-cholera victims. New breeding stock should usually be isolated for three weeks before putting them with hogs already on the place unless the latter be immune. 214 VETERINARY STUDIES This allows time for the disease to appear in case the new hogs have come from infected herds, through infected stockyards, or in infected cars. It is a mistake to visit your neighbor's hogpens, and walk about among the hogs out of mere curiosity, when your neigh- bor has told you that some peculiar sickness has appeared in his herd. It is a mistake to allow the last one or two sick hogs, which usually show a very chronic type of the disease, to linger for months on the farm. It is a better policy to kill such hogs promptly, and have done with the disease. They do not usually become thrifty and profitable feeders for a long time after re- covery. On the other hand, they may remain infectious to the last period of their sickness, thus keeping the yards and pens infected and furnishing a supply of infectious material for future outbreaks. It is a criminal mistake to leave carcasses in gullies, or throw carcasses into any stream, lake, or pond, or to bury them near such body of water. SuggestioTi. — An outbreak of hog cholera may be quarantined when it first appears; but it is extremely difficult to quarantine the disease after it has been scattered over several townships. Quarantine to be effective must be prompt and rigid ; partial or imperfect quarantine is worse than useless. iJisinfection. — The virus may live for months, under favor- able conditions. Sometimes the cheapest way to disinfect is to burn old sheds and pens where the siclc hogs have been con- fined. But if these structures are valuable, other means of dis- infection must be considered. Corrosive sublimate, dissolved in water in the proportion, of 7.5 grains to each pint, is a good disinfectant ; or, whitewasli that is made by adding fresh chlorid of lime, one half pound to the gallon, may be used instead of the corrosive sublimate solution. All bedding and loose stuff should be burned or plowed under. The gi'ound may be disinfected by saturating the surface with corrosive sublimate solution, or by burning off straw that lias been scattered over the surface, and the danger of infection may be lessened by plowing and planting the infected area. LECTURE XLIII COMMON MINOR DISEASES OF SWINE Posterior Parx\lysis Posterior paralysis is a rather conmion and serious condition affecting swine; it involves tlie hind quarters, and is probably a symptom of several different disorders. In some cases it is probably a disorder of the spinal cord ; in others, there is weak bone due to poorly balanced diet. Still others are due to injury inflicted b}' other stock, etc. Fracture of the femur or other leg bones' sometimes occurs in connection with rachitis (rickets), and is mistaken for paralysis. Rachitis may appear, like pa- ralysis in growing swine. Some cases are due to injury of the spinal cord. Paralysis often appears in heavy hogs after ship- ment by rail. Other cases are due to slow organic disease of the spinal cord, the direct cause of which is not known. A common type of posterior paralysis develops suddenly in old and heavy swine, particularly those in high flesh, and is due to simple constipation. Symptoms. — Some cases develop suddenly; others gradually. Those wliicli develop slowly show at first, irregular gait behind. The legs cross in walking; there is dil^culty in rising and a general lack of control for the hind legs. If the case develops suddenly, there is inability to use the hind limits, which are limp and weak — not unlike affected limbs of horses having azoturia. Hogs affected with this trouble often retain good appetite and are, apparently, in good health for weeks, having perfect control of the front limbs. If they move at all, Ihe liind limbs are dragged. Treatment. — For the heavy hog lacking in exercise, give a decided pliysic, 10 to 20 grains of calomel or else two compound cathartic i)ills in a small piece of pork; or 2 oz. castor oil. The rachitic form in young hogs is prevented by feeding skim milk, tankage, etc., and giving more exercise. 21.", 216 VETERINARY STUDIES Congestion op the Lungs Congestion of the lungs is essentially an engorgement of the pulmonary blood vessels, often caused by active exercise of swine in high flesh. Symptoms. — These cases are usually acute and are likely to end fatally. The symptoms are those of suffocation. There is marked distress and hurried respiration, the mouth being held open in an effort to get air. The pulse is rapid and weak, and the animal is apt to fall suddenly. On examination post mortem the pulmonary vessels arc found engorged and the lungs dark. Treatment. — If the condition of the hog permits, use a stimu- lant : aromatic spirits ammonia 1 to 2 drams, alcohol 4 drams, in water, repeated at short intervals ; for example, 15 minutes to one half hour. The animal must be kept warm and the ex- tremities rubbed vigorously. Extreme care is necessary in giv- ing liquid medicines in these cases to avoid killing the animal by suffocation. Hypodermic stimulants are safer. Constipation Constipation is a rather frequent cause of trouble among swine. Cause. — This trouble is very frequently associated with high feeding and lack of exercise, especially when the food is dry and lacking in laxative material. It rarely aff'ects hogs when on grass, clover, roots, pumpkins, or other fresh vegetables. Symptoms. — The aft'ected hog is restless, and occasionally strains as though trying to pass manure; its manure is hard and frequently covered with mucus^ and the hog becomes dull and loses appetite. Treatment. — Give 1 to 3 ounces of castor oil, depending on the size of the hog, or as a substitute for the oil give Epsom salts, in 1 to 3 ounce doses dissolved in warm water and admin- istered as a drench. For mild cases of simple constipation, old- fashioned senna tea, with rectal injections of warm water, is usually very satisfactory. It is necessary to exercise great caution in giving liquid medicine to hogs lest they be suffocated by drawing liquid into the lungs while squealing. COMMON MINOR DISEASES OF SWINE 217 A very simple method of drenching swine is to cut a hole in the toe of an old shoe ; insert the toe into the month, and allow the hog to chew it while the medicine is ponred in slowly and carefully. A short piece of ordinary garden hose with a funnel inserted at one end is also very satisfactory for this purpose. Or, put a piece of rubber hose on the neck of bottle, give medi- cine slowly and cautiously and, if possible, when the animal is not squealing. The animal may either be thrown down and held, or tied. A loop may be passed around the upper jaw back of the front teeth and held by a turn around a post, but, in this case, medicines must be given with great care. Black teeth. — Hlack teeth in young pigs are not of serious importance so far as the teeth are concerned. DIETETIC DISEASES LECTURE XLIV AZOTURIA Prevalence. — Azoturia is a common and very serious disease Avhicli nsually affects horses under certain well-defined condi- tions. It affects the best and most valuable horses and is fre- quently fatal. Farm horses in the North do comparatively little work during the winter, and are in high tiesh when early spring work opens. This condition, together with the fact that the early spring is necessarily a season of irregular work, will ex- plain why so many cases of azoturia occur during the spring months. History. — Azoturia rarely appears among horses at pasture or among those at regular work. It usually appears dur- ing exercise after a period of idleness, on full feed which has succeeded a previous period of work. Any severe exertion after an idle period may cause it, e.g., struggling in the casting harness or when halter-cast in the stall. This disease is frequently confounded with colic; sometimes farmers call it spinal disease, and sometimes an inflammation of the kidneys ; but it is easily distinguished from any of these by its history — which is very uniform — ^by the symptoms and by the condition of the urine. Duration. — Ordinary cases begin to either recover or fail within three or four days. The more severe cases may either die in a few days or develop a persistent and more or less com- plete paralysis of the hind quarters and limbs lasting weeks or even months. Causes. — The causes of azoturia are classified as predisposing and precipitating. The predisposing causea include high flesh, diet rich in pro- teid, and full feed during a period of rest following a period of regular work. Most cases appear during the prime of life. ]\Iares are more frequently affected than geldings, but all horses are subject to azoturia. 218 AZOTURIA 219 The precipitating factor is active exercise, following idleness on full feed. Symptoms. — The symptoms appear suddenly, with little or no warning?, and are very unifoi-m. The horse comes out of the stable fecliii<2: unusually well, tlien after ji:oinf]^ a short distance goes suddenly- lame, or stiff, or weak, in his hind legs. Both legs may be affected alike, or one only, or one first, then the other. Occasionally one or both front limbs are affected. The horse staggers, is very weak on his affected legs, and may fall before he can be unhitched. He perspires very freely ; the muscles over his loins and hips are rigid to the touch, frequently tender on i)ressure, and may tremble or twitch. The urine is highly colored, varying from red to almost l)laek, and increased in specific gravity. This abnormal color is due to the presence of red coloring matter of the blood and volun- tary muscles. It may not be conspicuous, however, in mild cases. Th(> pulse may run up to (iO oi- 80 per minute (normal, 42 to 48) ; and the temperature increase to 102 or 104 (normal about 101) if the animal is restless, l)ut in many cases they vary but little from normal. The bowels may be normal, and the appetite fairly good in mild cases. Skin sensation may be di- minished, as shown by pricking with a }un. The natural peris- taltic action of the intestines may be suppressed, but the bowels will usually empty under the influence of an injection or other local irritation. A chronic paralysis affecting one or both hind limbs may be a troublesome factor in the case. Prevention. — Prevention is simple, easily applied, inexpen- sive and reasonably certain, and for these reasons, preferable to treatment, which is frequently unsatisfactory even if the pa- tient recovers. Moreover one attack predisposes to another, and the second attack is more easily brought on than the first. Pre- venting tlie first attack may j)rev('nt several attacks and ulti- mate death of tlie horse. There is but slight danger of azoturia for the horse tlial is thin and weak, or for the young colt or for the aged horse. This disease often affects the best horse in the barn, one that is in good flesli and in the ])rime of life. AVhen such a horse has been working on full feed for ;i lime and tlien stands idle for a few days, or even twenty-four iioui-s, make a large reduction in the grain ration, or if tlie horse is (|uite fat, stop all the grain. 220 VETERINARY STUDIES A fat horse needs but little grain when standing idle. If he has worked recently, allow him plenty of water and turn him loose in the yard or exercise him every day if possible. If the grain has not been reduced as it should have been while the horse was idle, the next best course is to give him a decided cathartic, a quart of raw linseed oil for example, thirty-six hours before hitching, and then at first, work him very moderately for several hours as quick or violent exercise seems more likely to bring on an attack. Treatment. — At the first warning of azoturia stop working the horse immediately. Treatment should be done by competent veterinarians whenever such are accessible, for treatment is difficult. The principal purpose of this lesson is to direct attention to prevention and not toward treatment; but cases will arise, and these cases will occur in sections where competent veterinarians are not located. If not voided naturally, means should be taken to draw the urine as soon as possible after the disease appears, and three times daily thereafter. This may frequently be accomplished by inserting a hand in the rectum and pressing down moderately on the bladder. The azoturia patient has a much better chance for recovery if he can be kept upon his feet a portion of the time at least, and it is very desirable that this be done for several reasons ; but slings should not be used unless the patient can support a portion of his weight upon the limbs. When the patient is unable to do this, put him in a clean, dry stall with plenty of bedding and turn him every four hours, until he can stand with the aid of a sling. Quiet and rest are very important. Many different lines of treatment have been used by veteri- narians during recent years, with differing and even conflicting opinions as to results. Common baking soda has been used in large, half pound, doses. Some veterinarians with wide experi- ence believe they get best results with good nursing and very little medical treatment. For a cathartic, give one quart of raw linseed oil, or, better, one ounce of aloes with two drams ginger, made into a pill by mixing these with a little molasses. Encourage the horse to drink as much as possible. If he will not drink freely, he may be drenched with weak salt brine to make him thirsty. The AZOTURIA 221 more he drinks within reasonable limits the better. If restless and violent, he should have a sedative ; e.g. 1 ounce broraid of potassium witli 3 drams fluid extract of gelsemium, given in half a pint of sirup. If weather and stable conditions are favorable, the muscles of his hips and loins should be fomented with hot water twice daily, two hours each time during the first few days of illness ; after this treatment a stimulating liniment should be used over the muscles twice daily until the patient has recovered. "When chronic paralysis remains after the acute stage has passed, nux vomica should be used. Give one to two drams fluid extract nux vomica or one to three grains strychnin sul- phate twice daily in feed. Begin with small doses and gradually increase until there appear symptoms of nervousness and mus- cular twitching; then discontinue or rapidly reduce the dose. Prognosis. — Estimates of results must be made with great caution, for sudden and unexpected changes occur, A large percentage of azoturia cases die in general practice. Prognosis is bad when complete paralysis occurs; when the disease develops violently from the start, the horse going down at the beginning and soon losing control of both limbs ; or when the patient grows more and more restless during the progress of the disease, and is unable to support part of his weight in the sling. It is a hopeful sign if the patient can stand alone, or fairly well when assisted by sling. LECTURE XLV LYMPHANGITIS (ELEPHANT LEG) In general, lymphangitis is an inflammation of any lymphatic tissues, but in veterinary practice it usually refers to those of the hind leg of the horse. It appears suddenly and is quite painful, although rarely fatal. Cause and history. — This disease usually appears among heav;y' horses of sluggish temperament, such horses seeming much more susceptible than others, and it almost invariably occurs among those that are full fed and have had a period of idleness, perhaps of only one day. In some cases, it results from a local infection, in the foot, for example. Symptoms. — This disease usually makes its appearance with a chill, followed by fever. The horse is uneasy and in evident discomfort. A sudden extensive swelling appears on the upper inside portion of the hind limb. The swelling increases grad- ually, extending around the limb and downward. The lymph vessels are swollen and corded. Lymph glands high up in the inguinal region or groin become involved ; and these may even develop abscesses, but this is rare. Actual death of the patient from septic infection may even occur. The horse is quite lame, and the affected limb is very sensitive to the touch. He perspires freely ; the pulse is increased ; res- piration is somewhat hurried and the temperature is raised. The bowels are constipated and the urine is usually dark, colored, and scanty. Most of the swelling in the limb gradually subsides, and as this general swelling goes down, the inflamed lymph vessels ajipear as long, cordy swellings. Usuallj' some thickening and enlargement of the leg remains and this disease is apt to recur, each time leaving a somewhat increased enlargement until finally there develops what is commonly known as elephant leg. Lymphangitis might be confused with simple dropsy or with glanders. It can be distinguished from simple dropsy, however, by its acute pain, its fever, lameness, and cordy swellings ; and 222 LYMPHANGITIS (ELEPHANT LEG) 223 it may be distinguished from the farcy form of glanders by its more acute fever and more acute local trouble in the leg; by its early inflammation of lymph glands in the groin, its absence of farcy buds, and failure to react to mallein test. Prevention. — The grain ration should be very greatly reduced during idle periods. This is true for any horse in fairly good tlesh, and particularly true of horses of the type that has been mentioned as especially subject to lymphangitis. Treatment. — Prompt and vigorous treatment seems to abort the disease in a fair proportion of cases. Hot fomentations over the swollen part, continued for several hours, are one of the most important parts of the treatment. Bet^Yeen the periods of fo- mentation there should be given a vigorous friction — rubbing upward — and long-continued light exercise. If the horse is able to walk, he should be kept moving about slowly for several hours at a time. During the first 3 or -4 days, and until the active symptoms abate and the horse is again receiving normal exercise, the food should be light and laxative. Later full feed may be resumed. For acute cases with high fever, four or five quarts of blood may be drawn from the jugular vein. A moderate physic should be given : e.g., 4 to 8 drams of aloes in a physic ball ; or, 14 pound Epsom salts dissolved in a pint or more of water, 3 times a day may be substituted for the aloes. One-ounce doses of acetate of potash, dissolved in two pints of water and used as a drench,* or given in the drinking water — if the horse will take it so — should be given three times daily for a day or two. Prognosis. — Lymphangitis usually ends in recovery so far as the general disturbances are concerned. Something may be estimated concerning the i)robable severity and duration of ill- ness by noting the severity of the chill which comes at the begin- ning of the attack. LECTURE XLVI LAMINITIS (FOUNDER) Laminitis is a painful and rather frequent disease most com- mon in horses but other classes of stock are subject to it. It is commonly called founder and is essentially an inflamma- tion of the sensitive parts within the hoof, especially the sensi- tive lamina?. Founder is more common in the front feet, but may affect either or both the front and hind feet. Symptoms. — The horse shows unmistakable evidence of ex- treme pain and usually persists in lying down. The pain is due to the fact that the horny wall and sole do not permit the inflamed tissues to expand. Respiration, pulse, and tempera- ture may increase as a direct result of the pain ; the fever may be marked, the pulse full and strong, and the attitude and expression indicating anxiety. If the front feet are affected, the horse carries as much of the weight as possible upon the hind feet, the two front limbs extending forward. If the hind feet are involved, he extends them forward and stands with the front feet back, under the body, and carrying as much weight as possible to relieve the sensitive hind feet from pressure. He refuses to back, and the artery (planter) just above the ankle throbs. There is often excessive perspiration and a tendency to constipation unless the case be associated with excessive diarrhea. Causes. — Laminitis frequently results from disturbances of the digestive organs, due to unusual over-feeding, for example, or to a large quantity of cold water, drunk when a horse is very hot or tired. It may be caused by unaccustomed concussion on hard roads, in case of a horse not accustomed to this work, or by exhaustion, and exposure to cold wind or cold water. Lami- nitis often occurs in one front foot, or one hind foot, as an indi- rect result of lameness in the opposite limb ; the horse overworks the sound limb in order to relieve pain in the lame one, and thus causes laminitis in the foot which had been sound. Lami- nitis is frequently associated with parturition (delivery) in the 224 LAMLNITIS (FOUNDER) 225 mare or cow, or with pneumonia, or bronchitis. Laminitis espe- cially is apt to occur in a horse that is worked during a period of digestive disturbance. Pathology. — There is first of all an inflammation of the sensi- tive parts within the hoof, especially tlie sensitive laminte, and velvety tissue. In severe cases, this inflammation may become supi)urative. This early inflammation is followed by an exu- date, which may be either slight or profuse and more or less persistent. In persistent eases with considerable exudate, the toe of the os pedis (third phalanx) is gradually drawn dowuAvard against the sole, leaving the sole convex, and the horse per- manently unsound. Termination. — Lami- nitis may terminate in re- covery and practical res- toration of the affected fig. 76.— Foundered Hoof, (B. A. I.) parts, or there may remain Au old case. a convex sole and a chronic soreness with a tendency for the hoof to grow to an unnatural shape. See Figiire 76. In the latter case, the wall becomes wrinkled transversely, and grows unevenly. Treatment. — These are usually serious cases, and call for pro- fessional attendance and skill if such is obtainable. Any general treatment that could be suggested might be unwise in some cases, and wrongly applied in others. A treatment that is frequently satisfactory consists in keep- ing the feet wrapped with burlap and wet with cold water for some time — several days if necessary. Sometimes this may be done by standing the horse in a shallow stream, preferably with a soft bottom, or a pack of crushed ice maj^ be used. If he is compelled to stand for any great length of time in order to keep the feet in cold water, then he should be sup- ported by a sling. AYhen a horse must be kept in the stable, he should have a large box stall with deep, soft bedding. Severe cathartics must be avoided, but it may be desirable to give very mild doses of aloes, or raw linseed oil. A dose of aloes for this purpose would be one half ounce or less; that of the oil would be about one pint, either one repeated as necessary. Two to 226 VETERINARY STUDIES three or even four, ounces of saltpeter also may be given, dis- solved in drinking water, or as a drench in a pint of water, three times daily. Large doses of alum often give especially good results, particularly in cases where the foot trouble follows a digestive disturbance. The alum is administered in 2-ounce doses every two hours, each dose dissolved in one quart of water and continued if necessary until a limit of six or eight doses have been given. During this treatment little water is allowed. Ordinarily the shoes should be removed and the toe, if long, shortened ; but the sole should not be thinned or otherwise inter- fered with. If the horse is compelled to stand he may do so more comfortably with shoes that are rounded, high in the center and thin at toe and heels. If the pain is extreme, and not eased by soft bedding and continuous application of cold water, then som.ething should be given to relieve it. If an acute case can be induced to lie down, great relief and rapid improve- ment in respiration, pulse, and pain are soon noted. Prevention. — Intelligent care will prevent many ordinary cases of laminitis. Accustom horses to markedly changed con- ditions gradually. This applies especially in case of fat and idle horses put to work and to country horses put on city pave- ment. Keep a heated horse out of cold winds and cold water. Avoid overfeeding and overdriving, and feed a hot horse or tired horse very cautiously. LECTURE XLVII HEAVES This is a disease of horses. It is characterized by a peculiar disturbance of respiration, in which althoujjjh inspiration is about normal, there is difficult expiration, the air being expelled by two distinct movements instead of the normal one. True heaves is usually associated with the feeding of consid- erable quantities of timothy and clover hay — especially dusty hay — and it lessens very materially the value and usefulness of horses affected by it. Light feeders are as a rule free from this disorder, while horses that eat hay greedily are most liable to have it. In the lungs of horses so affected, the air vesicles are gradually dilated, losing their elasticity; they may even rupture together so as to produce small cavities, from which the air is expelled with great difficulty. During forced expiration, the air may escape into the surrounding tissue. This escape of air from the air cells into the lung tissues (emphysema) usually occurs in connection with heaves, but its relation to the disease is quite problematical. Plainly a horse may have such air leakage with- out heaves. This condition is probably to be regarded as an effect rather than a cause. Cause. — Any chronic irritation of the bronchial mucous mem- brane may cause heaves — chronic bronchitis and severe cough, for example, or repeated violent exercise by a horse not in condition. But we may say that the usual direct cause of heaves is the excessive eating of bulky food, especially hay that is overripe and dusty,— or worse, musty. Tame hay cut very ripe and dusty clover hay are both prone to cause tliis trouble, which rarely, if ever, develops in horses on pasture or that have only bright, wild hay or a reasonable (|uantity of early-cut tame hay. This disease is said to be almost unknown in arid regions where timothy and clover hay are grown by irrigation, and where such hay is never exposed to dew or rain and there- fore does not develop fungi to a serious extent. Mere bulk and 227 228 VETERINARY STUDIES over-ripeness are probably not the only factors. Many eases of heaves may be due to fungi, especially their spores, rather than to the character of the food with which the fungi are taken. Symptoms. — A peculiar, explosive cough usually appears be- fore the breathing becomes noticeably disturbed. After a time it is noticed that exercise produces unusual difficulty in breath- ing, the air being taken in quite easily but expelled with dif- ficulty. When this stage develops, the air is expelled in two efforts instead of one, the latter portion of the tidal air being expelled by a special effort of the belly muscles. Overfeeding, of course, increases the difficulty. Some cases of heaves may be disguised temporarily by the use of drugs and the feeding of a concentrated diet. This trick may usually be detected, however, by allowing the horse a hearty feed and water, and then giving active exercise or even by actively exercising him without the special feeding and water- ing. A horse drugged with any belladonna preparation shows greatly enlarged pupils of the eyes. It is usually easy to dis- tinguish between heaves and roaring. The latter is a disease of the larynx due to paralysis of one of the laryngeal carti- lages and is shown by the abnormal sounds known as roaring or whistling during inspiration, the movements of the flank and chest being normal. Prevention. — The prevention of most cases of heaves may be easily described and almost as easily accomplished — by mere avoidance of well-known causes. There is a very general and wasteful feeding of hay. This is not merely a waste; it is an injury to the horse. A case of heaves due to over-feeding is usually discredit to the feeder. Heaves often indicates that the horse is a good feeder and under wiser management would be able to digest a large amount of food and do hard work. There is no satisfactory evidence that heaves is hereditary, and no proof to the contrary. It is not wise to allow a horse to do very fast or hard work on a distended stomach, which means that the work should be slower and easier during the first hour or so after hearty meals. Little hay should be fed in the morning, and at noon, and a reasonable quantity in the evening. To prevent heaves, then, feed reasonable quantities of good wild hay, or tame hay cut early and not allowed to become musty. Avoid dusty foods. The amount of hay should be HEAVES 229 restricted to much less than is usually fed. Horses that are greedy feeders should be bedded with sawdust or shavings or protected by a muzzle in case other bedding is used. Autopsy. — On examination post mortem, the lungs may be found to be somewhat bloated and to contain more air than normal. The chambers in the right side of the heart are apt to be enlarged and their walls tliickened. In examining the lungs of long-standing cases of heaves, we note that they are pale and tloat abnormally high in water, due to the emphysema or air in the tissues previously mentioned. The stomach is often larger than normal, due to the overeating of bulky foods and conse- quent stretching. Treatment. — In cases of heaves avoid overripe and dusty hay. Allow little bulky food of any kind. Give a small quantity of hay for the morning feed, none at noon, and a very moderate amount in the evening — much less than would be considered care- ful feeding for a healthy horse. If the hay or grain is dusty, sprinkle it as a regular custom. Use such horses for slow work, and give as much rest as possible after meals. A month or two of this management will very greatly improve most cases. ]\Iedical treatment is considered unsatisfactory so far as cura- tive effect in bad cases is concerned. Fowler's solution in one- ounce doses three times a day in the feed, long continued and coupled with careful feeding, is often a great help. Proper feeding alone may be said to be almost curative, although sub- sequent attacks are easily brought on by injudicious manage- ment. LECTURE XLVIII HOVEN, OR BLOAT (ACUTE TYMPANITES) Hoven, or bloat, is a form of indigestion in cattle and sheep which is characterized by an abnormal collection of gas in the first stomach or paunch. Causes. — Bloat is caused by excessive fermentation, which results indirectly from such conditions as sudden changes from dry food to pasture, or from one pasture to a better one, or Fig. 77. — Showing Where to Tap. (M. H. E.) See white cross in the flank. from grass to clover. Easily fermented foods favor lioven. Grasses or clovers, wet by dew or rain, seem especially apt to cause hoven. Frosted roots and impaction from overfeeding may also re- sult in arrested digestion, and then hoven ensues. Sick cattle frequently bloat after lying for a long time on the side. Choke often leads to hoven. 230 HOVEN, OR BLOAT (ACUTE TYMPANITES) 231 Symptoms. — There is extreme distention of the stomach, most prominent on the left side with consequent difficulty in breath- ing:. The pulse may be nearly imperceptible. The animal moans, may stagger and fall, then die in convulsions. Treatment. — If breathing is difficult, do not wait for the ef- fect of medicines ; sheep require very prompt treatment to save them. Tap with trocar and cannula, high in the left flank and well forward. (See Fig. 77.) The tube (cannula) may be left in the flank for some time if gas continues to accumulate. Then give the following as one dose in one pint of sirup: — (A) Arinnalic sjiirils of ainiiioiiiu 2 oz. Tuiiioiitiiie 2 oz. This is a suitable dose for a thousand pounds live weight. Repeat this in half an hour if necessary or give one double dose ; or give (B) 4 oz. hyposulphite of soda in 6 ounces water every half hour until gas ceases to accumulate or until a limit Fig. 78. — Trocar and Cannxtla. For tapping bloated sheep and cattle. of six doses have been given. A third method consists of alter- nating the two doses (A and B) just described at half hour intervals. Half an ounce of formalin in a cpiart of water is a very effec- tive remedy. For mild cases, a large hay rope placed in the mouth and tied around the liead is useful. Vigorous massage of the l)elly by two men witli a limber pole is useful in such cases. Both of the latter methods are more effective when sheep are made to stand high in front, or on their hind legs or when cattle are made to stand with the front i)arts high as possible. Do not exercise a badly bloated cow or sheep. To do .so is dangerous, because the breathing is interfered with by the pres- sure of the stomach against the diai)liragm. When the acute symptoms have subsided give the following for physic: 232 VETERINARY STUDIES Epsom salts 1 lb. Glauber salts Va Ginger (gTOund) 3 oz, F. e. nux vomica 3 drams Dissolve these in three pints hot water and use the solution as a drench; repeat in 16 hours if bowels do not move freely. Prognosis. — A large percentage of cases recover if properly treated soon after disease appears. Death occurs from asphyxia, rupture of the paunch, or rupture of the diaphragm. Prevention.— H oven is likely to be quickly fatal to sheep; hence, sheep should be closely watched, when they are first put on dangerous feed like green clover, rape or alfalfa. A large proportion of these cases may be prevented, but some will ap- pear occasionally under conditions which cannot be prevented. There are two reasonably safe methods of turning cattle and sheep on new pasture at any season; from a poor to a richer pasture; or from grass to clover. First, feed heavily and then turn them on the new pasture for a few minutes the first day, and increase this time a little each day for a week. Or second, give the cattle or sheep a large ration of the dry food to which they have been accustomed, for several days before they are to be turned on the new feed; feed later than usual on the last morning and then turn them out as soon as they are done eat- ing, which should be after the dew is off the grass and not soon after a rain. Under these conditions, cattle and sheep usually may be turned on grass in the spring or put on new or dif- ferent pasture and left there with little risk. Pastures where the old grass stands quite heavy, and the young grass has grown up in it, are much less dangerous than those where the stock gets only the new grass. When cattle or sheep are once safely on a rank pasture, or clover, alfalfa, etc., the more continuously they can be left there, the safer they are. LECTURE XLTX PARTURIENT PARALYSIS (MILK FEVER) This serious disease of eows usually appears within a very- few days after calving;, althougfh it may appear before or some time after calving. Its cause, nature, and pathology are not well understood. However, prevention and treatment are, as a rule, very satisfactory. Fig. 79. — Partitrient Paralysis — ^Milk Fever. {M. H. R.) Early stage. Unsteady on hind legs. Causes. — The causes of parturient paralysis are of two classes, predisposing and precipitating. Predisposing causes include age (maturity), heavy feeding and milking qualities, pregnancy, easy delivery, lack of exer- cise, and high temperature in stables. The cow that is a heavy feeder and milker and in the prime of life, with her third or 233 234 VETERINARY STUDIES fourth calf, is the one most subject to this disease. A young heifer, an old cow, or a cow in thin flesh and underfed during pregnancy, is not likely to have this disease. Precipitating causes include delivery, sudden increase of gland activity in the udder, disturbance of circulation, anxiety and exposure to cold and damp. Symptoms. — These are known as: early or warning, and diagnostic, or positive. mmm -amm. ^im^ <-^*5»- Fig. 80. — Partukient Paralysis. (M. H. E.) Later stage. Head held unsteadily. Early symptoms. — Uneasiness, sudden constipation, eyes either stupid or wild, tail switching uneasily, and checked milk flow are early symptoms of milk fever. The gait is peculiar, show- ing imperfect control of the posterior limbs. Such symptoms, if occurring during the first five days after calving, or within two days before should warn of danger. Diagnostic symptoms.— The patient goes down, is more or less unconscious and lies in a peculiar position, with her head in the flank; she loses sensation and power of voluntary motion, the sensory and motor nerves become paralyzed; her pupils dilate; she is unable to swallow; her pulse, at first bounding and full, is later depressed; her temperature is usually normal, or even sub-normal; respirations are slow. In typical cases, the symp- PARTURIENT PARALYSIS (MILK FEVER) 235 toms are uniform and plain; but some atypical eases are not easily recoguizocl. Prevention. — Prevention is always more satisfactory than treatment. P'or a heavy milker, sudden changes in diet are to be avoided, unless toward one lighter and more laxative just before calving. It is sometimes advisable to change especially susceptible cows from pasture to light, dry feed. Food should be light, laxative, easily digested, and small or moderate in quantity. Exercise is desirable. A mild laxative may be given .ur^X.^f^=3^r Fig. 81. — Parturient Paralysis. Cow very stupid. Skin has lost sensation. Head in the flank. Still later stage. 2 to 5 days before calving, one quart raw linseed oil, for ex- ample. Allow the cow abundant exercise during the last month of pregnancy, and, if she is nervous, leave the calf near hei- for a few days. Usually there should be no milk drawn before calving and but little removed during the fii'st twenty-four hours afterward, not more than the calf would take naturally. This precau- tion is especially important as a preventive of milk fever in high-type dairy cows, and is reasonably satisfactory if followed with intelligence. Treatment. — Acute cases are liable to die in 12 to 24 hours if not treated ; others may improve greatly and then relapse. Since these cases require skilful treatment, and the affected animals are usually valuable, stockmen sliould not treat them if com- petent veterinary services may be had. A line of treatment is 236 VETERINARY STUDIES suggested here because cases for the stockman however fre- quently occur where it is not possible to obtain professional assistance. The patient must not be allowed to lie flat on the side on account of danger from hoven, but should be propped up by means of bags of sand, bran, or hay, so that she lies on the sternum. If the head is thrown around violently, it should be supported by means of a rope tied to some overhead support. The cow must also be kept quiet and thoroughly warm and dry. Severe cases may require stimulants, like strychnin or camphor oil (1:4) hypodermically injected. Retain heat in cold weather by a covering of four or five blankets. Draw urine twice daily and use large quantities of slightly irritating rectal injections repeated several times, if necessary. Give no medicine or liquid food by the mouth, except as directed by a competent veteri- narian, bcause of difficult swallowing and the danger of pro- ducing fatal pneumonia in a case that should have recovered. Air treatment. — The injection treatment for milk fever has passed gradually through several stages from iodid of potash solution (Schmidt treatment) to various other solutions, then to oxygen gas, and finally to simple, clean air. This air-injection treatment is the one now in most common use. Apparently full distention of the udder is the essential thing, and it matters little what is used for the purpose providing it be clean and not irritating. Great care in cleanliness is necessary to avoid in- fection of the interior of teat and udder with germs which might cause garget or septicemia (blood poisoning). The udder and teats should be well brushed, then placed on a clean towel or piece of oilcloth and disinfected with 1 to 1000 corrosive sublimate in water, or 3 per cent lysol or creolin, or 5 per cent carbolic acid. The hands of the operator, the teat tube, the rubber tubing, etc., should all be disinfected, the two latter by boiling. After the teat tube is disinfected, it should not be carelessly handled or be allowed in contact with anything that can contaminate it. Bacterial cleanliness is of the utmost im- portance. Air is injected by a special syringe in which it is filtered through cotton before entering the udder. The utmost care must be taken as to clean handling and the injection of clean air. Tlie quarters are milked out and pumped full of the filtered air; it is well to give the udder massage treatment in order to disseminate the air through the milk ducts during the PARTURIENT PARALYSIS (MILK FEVER) 237 injection process. A broad tape is tied around the teat and left on for about six hours. The injection may be repeated in three to six hours if neces- sary. In an emergency, an ordinary bicycle pump connected by rubber tubing to a milk tube may be used, but this, of course, does not filter the air. Prognosis. — It is difficult to make an accurate estimate. But there is in general a good prospect of recovery in serious look- ing cases if they are properly and promptly treated. Sudden and unexpected variations occur. Mortality under the air treatment is not large. The prospect is less favorable if the ease develops soon after calving ; if it develops rapidly and seems to overwhelm the system ; if there is decided loss of animal heat ; if tjTiipanites or bloating, or convulsion occurs ; if the cornea becomes insensible ; if the lower lip hangs loosely. The prospect is favorable if : the circulation remains good ; if feces are passed ; or the patient attempts to rise or eat ; if rectal irritation causes a discharge of feces, or a subnormal tem- perature changes to normal. LECTURE L CHOKE Choking, as ordinarily understood, is an obstruction in any portion of the pharynx or esophagus. In horses it is more com- monly caused by diy food, rapidly eaten. Cases in which a long section of the esophagus is packed with soft, dry food are especially difficult to handle successfully. Cows more frequently choke on pieces of roots, pumpkins, and even old bones. Symptoms. — The horse or cow stops eating suddenly and makes ineffectual efforts to swallow, then there are spasmodic actions of the neck and belly muscles. When the animal at- tempts to drink, some of the water returns through the nose. If the obstruction is of considerable size and is located along the neck portion of the esophagus, it may usually be seen or felt. There is usually a profuse flow of saliva, and particularly in the case of cattle an involuntary chewing action. If the chok- ing occurs in the thoracic portion, then medicines or liquids are swallowed in small quantities without difficulty until the esophagus is full, when they return by the mouth, causing the animal to cough. There is usually marked dejection and dis- tress, with an appearance of anxiety, food and water are re- fused. Cattle frequently bloat. Prevention. — Roots should be sliced or pulped unless they are large. Cows often choke when eating hurriedly, especially when attempting to swallow under threatened attack from some other member of the herd. Hence individual feeding lessens this. Horses choking on dry feed are almost invariably rapid eaters, and for such horses it is well to avoid dry bran. Grain, espe- cially oats or similar food, should be fed in such a way that the horse gets it slowly; it may be scattered over the bottom of a large manger, for instance — any device which forces the horse to eat slowly lessens the difficulty. It should also be borne in mind that an animal which has once choked is liable to a stric- ture, with consequent recurrence of the same difficulty, during the first week or two after the accident. 238 CHOKE 239 Treatment. — In case of choke, food, drink, or medicine may easily cause a fatal pneumonia, by entering the lungs through the pharynx; hence the need of great caution. If the obstruction is within reach, it should be removed by the hand, the teeth being held apart by some suitable device to protect the arm. A person with long arm and slender hand can frequently relieve choking in the pharynx or upper portion of the gullet, especially if he has an assistant to shove the obstruc- tion upward toward the hand. A thin glove with the ends of the fingers cut off is desirable for protecting the hand. Dry food that cannot be reached by hand should be softened by the use of oily or mucilaginous drinks, and then gradually worked loose by external manipulation. Frequently the ob- structing mass can be loosened at the lower portion, a little at a time, and the loosened portion swallowed. Fig. 82. — For Relieving Choke. {M. IT. E.) Made of No. 10 or 12 wire. If the choke is along the neck, and caused by dry feed like oats or bran, then water or raw linseed oil injected directly into the dry mass with a good hypodermic syringe may soften and dislodge the obstruction. A case of this kind may often be relieved by washing the feed out through a double-current stomach tube. A single-current tube may be used to siphon out soft feed. Loosen the upper portion of the mass with the fingers, then fill the tube with water, drop the outer end, and siphon out. Repeat as many times as necessary. For this pur- pose, or for use as a probang, a small sized lawn hose, well oiled, does very well. This method is applicable whether the obstruction is in the neck or within the chest. A probang should not be used in cases where the trouble is due to di*y food. The simple device shown in Figure 82 is very satisfactory for relieving choke due to ]neces of vegetables. It consists of a piece of No. 10 to 12 wiic, about 12 feet long, the ends bent together and twisted as shown in the cut, leaving a suitable loop at the point which was origiiuilly the middle of the wire. This instrument is introduced into the gullet. The farther end passes the obstruction, which is then included by the loop. By pulling 240 VETERINARY STUDIES on the wire the obstruction is loosened, moved upward a short distance, or removed entirely. If the obstruction is merely loosened then the process is to be repeated. This has proven fairly satisfactory in the writer's experience. In all such work the nose should be extended, the gullet be kept in as straight a line as possible, and the work be done carefully. The tube or wire loop should be introduced slowly and carefully, high up and well back in the mouth. If the animal coughs, the instru- ment should be removed and another trial made, as the cough- ing indicates that the instrument has entered the trachea. Tense, spasmodic action of the gullet gripping the choke may be controlled by the use of morphin or aconite. AVhips and other stiff instruments must be avoided, as they are apt to tear the gullet just below the pharynx. Whatever is used must be smooth and flexible. For at least a week after the removal of the obstruction, the diet should consist of soft food. There is usually no reason for haste in treating choke. Some cases will recover naturally if water is kept before them and they are left quietly alone. However, in severe cases, and when ordinary measures fail, call your veterinarian before you have bruised and torn the esophagus, making the case hopeless. MISCELLANEOUS DISEASES LECTURE LI UNSOUNDNESS If at any time a horse has any disease {e.g. bone spavin or heaves) which actually makes him less capable of his proper work, or which in its ordinary progress will diminish his natural usefulness, he is unsound. A blemish, e.g. a barb-wire sear, impairs appearance and sale value, but not actual service, and is not an unsoundness. Soundness is usually relative, being; rarely if ever absolute or perfect. What we mean in passing a horse as sound, is that he is practically sound. To be sound, then, a horse must have no disease or other con- dition that interferes or is likely to interfere with his useful- ness. For instance, a horse may have a spavin, which both les- sens his ability to work and injures his selling value. The same would be true of heaves. A horse may have a disease from which he will recover ; but at the time of examination, he "will be technically unsound. Unsoundness may be temporary or permanent. Temporary unsoundness may be illustrated by an intluenza, from which a horse would probal)ly recover, or by a light sprain or an ankle bruised from interfering. In the latter case the question would arise at once as to whether the interfering was due to faulty conformation or to faulty shoeing, for the latter could be easily remedied. In the former case the condition would be incur- able and serious; in the latter condition it would be unim- portant. Normal conditions. — It is necessary first of all to become familiar with the usual and unusual normal conditions and ap- pearances for comparison. For instance, the hocks may be perfectly sound, and yet have peculiar bony development. In such case it will be found that both hocks are alike. The knees may have a similar i)e('uliar development, and yet be perfectly sound. 241 242 VETERINARY STUDIES Common Unsoundness and Blemishes Ringbones, splints, spavins, etc., are abnormal developments of bone tissue, the result of an inflammation of the periosteum. These are all recognized as forms of unsoundness, and usually cause lameness. The inflammation of the periosteum may have its origin in bruises or other injuries, or it may possibly be the Fig. 8.3. — Eingbones. (M. E. B.) 1. Ring-bone and sidebone, with general anchylosis. 2. Ringbone and sidebone, with general anchylosis and marked bony en- largement. 3. High ringbone with anchylosis on first and second phalanges. 4. Low ringbone with sidebone, and anchylosis of the second and third phalanges. 5. Ringbone with sidebone^ and unilateral anchylosis. result of an extending inflammation from some adjoining tissue, but in either case the result is usually a projecting development of bony tissue, i.e., an exostosis. Hereditary tendency is an- other important item among causes. Ringbone. — This is characterized by an exostosis on some por- tion of the pastern bones. It may be in front, behind, on either side, or extending entirely around the pastern. It may be lo- cated near the crown of the hoof or very much higher. Some ringbones involve the articulation, and are then called articular. UNSOUNDNESS 243 These necessarily cause lameness. Others affect the extremity or the shaft of the bones witlioiit involving the articulation. Some are due to injury, others are of rachitic origin (rickets), and due to faulty nutrition resulting in poor (juality of bone. Ringbones are usually much more serious forms of unsound- ness than splints, as they are more apt to be permanent in effect, and even if the soreness be relieved, there is likely to be a me- chanical lameness because of a stiffened joint. This unsound- ness and the lameness resulting from it are very easily detected in plain cases. Sidebones. — A sidebone is an abnormal condition of the lat- eral cartilage— most common on the external cartilages of the front feet — characterized by firmness under pressure and some- Fig. 84.— Sidebones. (M. H. B.) Due to an inflammation and ossification of the lateral cartilages: 1, nor- mal OS pedis; 2, 3, 4, varying types of sidebones. times enlargement. These cartilages are normally quite elastic. The firmness is due primarily to a deposit of lime, a process of ossification, i.e., bone formation — in the cartilage structure. Sidebones are detected as bonelike structures which appear above the crown of the hoof at tlie quarter and just beneath the skin on either side. They may or may not cause lameness during the period of inflammation and hardening. In some cases the lameness is persistent. Otlier cases are very slow and mild and no lameness is noticed. Spavin. — Bone spavin is one of the most serious forms of unsoundness. This is a disease of the tarsal bones at the lower, inner, front portion of the hock. There is usually something of an exostosis, varying from very small size, commonly called by horsemen a "jack," to very large size which every one rec- ognizes as bone spavin. There is another form of bone spavin in which there is a slight or no external development. In this form there is disease 244 VETERINARY STUDIES of the bones in the deeper parts ; and erosions of the articular cartilages. Bone spavins have a tendency to recover without treatment, although in many cases the period required for natural recovery is very long, extending through a period of years. In other cases recovery can never occur. Recovery when brought about by natural or artificial conditions implies that certain of the tarsal bones have united, a process called anchylosis, i.e., union. Inflamed, sensitive surfaces are then no longer rubbing together as the limbs move. Fig. 85.— Spavins. Two Types. (M. E. B.) I. Spavin with marked bony enlargement. A, metatarsals; B, tarsals with enlargement and anchylosis. II. Blind spavin. Extensive ulceration of articular surfaces ; no en- largement; no anchylosis. 2, os calcis; 3, scaphoid or large cuneiform. ]\Iany bone spavins doubtless appear as the result of slight injuries in susceptible subjects, particularly those that have a strong hereditary tendency to disease of this kind. Symptoms. — These cases come out very lame after hard work, step on the toe, and improve with exercise. They often stand with the foot resting in a peculiar way against the other hind foot. In motion they carry the hock joint with as little move- ment as possible and step on the toe. What is known as the hock test is made by holding up the limb, with the hock sharply bent, for several minutes, then the horse is started suddenly. In case of spavin the first few steps are very lame. Old horses without spavin may respond to this test and so lead to error if one is not careful. UNSOUNDNESS 245 Splints.— Splints apperr as small tumors of various shapes and sizes along the metacarpal bones, usually at the junction of the large and small metacarpals. They are generally more seri- ous when located near the knee. Occasionally there appears what is known as a pegged splint, in which the growth extends across the back of the cannon, beneath the suspensory ligament. It is important to avoid mistaking for a splint, the nor- mal enlargement on the inferior extremity of the inner meta- carpal. The lameness which results from splints is recognized by lo- cating the splint and noting sensitiveness on pressure over this point. The horse walks nearly or quite "sound," but trots very "lame," especially on hard ground, lie is apt to get worse after long exercise and is worse on rough, hard road. There is a natural tendency to recover. For this reason lame- ness from splints is rarely seen in aged horses. When the splint appears very close to the knee, or in the pegged form, there is less prospect of natural recovery, and, with the latter form, lameness is very apt to be permanent, unless relieved by surgical means. Curb. — A curb is a result of injury or strain of a short liga- ment at the back of the hock joint, and is characterized at first by a hot, sensitive swelling just back of the lowest part of the hock joint. After the period of swelling and inflammation sub- sides, there is apt to remain a hard tumor, particularly on what is known as curby hocks. In cases of young animals with other- wise good legs, proper treatment may reduce the enlargement to slight size or practically remove it. Capped hock. — This is a soft enlargement, on the point of the hock, and is produced by bruises. Some horses get it by back- ing up against the stalls and striking so as to injure the i)oint of the hock; bruises may be received during car shipment. The first swelling may usually be reduced by prompt treatment, but upon slight injury it returns and after several attacks is apt to be permanent. A capped hock does not injure a horse for actual use, ])ut it is unsightly, and materially reduces sale value. Shoe boil. — Shoe boil appears as an enlargement on the jioint of the elbow or superior extremity of the ulna. It is very simi- lar to capped hock in cause, character of structures involved, and subsequent history. Shoe boils are unsightly and injure sale, but do not cause lameness. 246 VETERINARY STUDIES Synovial sacs. — The ordinary wind puffs, bog spavins, and thoroughpins are typical illustrations of enlarged synovial sacs. Thej' are not usually the cause of lameness and are to be re- garded rather as blemishes and indications. They are common in overgrown draft colts that have not had sufficient exercise. Wind puffs are found just above the ankles and in mature horses usually indicate too much hard work. Bog spavins are enlargements of the synovial sac of the hock joint, and appear on the inner and front part of the hock. They are often hereditary. Thoroughpins are similar to bog spavins and wind puffs, ex- cept in location. Thoroughpins appear at the upper and back part of the hock. They may or may not connect with the syno- vial sac of the hock joint. Open joint is usually the result of puncture of the synovial sac and the entrance of bacteria, which cause an acute inflam- mation, known as synovitis. This form of lameness can usually be very easily detected, and the cause recognized. It is very serious under all circumstances, and frequently results in death. The veterinarian should be called at once. Hygromas. — These are enlargements of serous sacs at promi- nent points and due to injury. They are found at the elbow, knee, external angle of ilium, point of the hock, "pin bone," point of shoulder, etc. They sometimes have thick, hard walls. A common example is found at the knees of stabled cows. Miscellaneous. — Corns usually appear at the inner heel of the front foot — in the angle between the bar and wall. They may be caused by bruise of the sole but more commonly by lateral pressure of the weight from above upon the sensitive laminte and velvety tissue in a contracted heel. They appear as bruised areas under the sole at the point mentioned. The wall at the affected heel is apt to show ridges which are not parallel with the coronary band. A horse with a corn frequently "points" as in a case of navicular disease. In case the bruised area becomes infected, pus forms and eventually discharges at the coronary band. The case is then known as a "quittor." Navicular disease is a slowly developing, chronic affection of the navicular articulation. The navicular bone, with its articu- lar cartilage, the deep flexor tendon, and synovial membrane at that point may be involved in the inflammation and its re- UNSOUNDNESS 247 i5ults. The disease is more common among light harness horses. It is detected by "pointing" in the stabk's; after the case is well developed, lameness grows worse if the horse continnes to work and generally improves with long rest only to return again with work. The history of navicular trouble is significant. Slow and vague in its onset, the lameness is variable and irregular at first. Later the horse "goes on his toes" in a stilty manner and Fig. 86. — Navicular Disease. (M. U. E.) 1. Normal navicular bone. 2. p]xostosis (bouv enlargenicnt) with fracture. 3. Exostosis with 'extensive ulceration of the articular surface. 4. 5, 6, 7. Varying types of exostosis. Stumbles easily if both feet are affected. There may be heat in the hollow of the heels and pressure of the thumb in this hollow together with sharp flexion of the toe causes increased lameness when the liorse is made to move. Dummy. — ^A dummy is a horse with a l)rain disease which is indicated by peculiar attitude and stupid actions. The liorse is listless, stands with his licad down, jicrhaps resting it on the manger and fre(|ucntly rests one foot upon the coronet of the other. He drinks with his mouth deep in the water; walks with his head low, although stepping high or dragging tiie feet; is unal)le to back; and is subject to sudden brain disturbances such as unreasonable fright and panic. Such a horse will usually leave the front legs crossed if they are put in this un- 248 VETERINARY STUDIES natural position by the examiner. A sound horse will not do this unless trained to do so. Roaring, ivhistling, heaves. — These disorders of the respira- tory organs have been previously described as serious and chronic and should not be overlooked. Heart disease. — This trouble is indicated by violent or irregu- lar heart action, inability to stand exertion, etc. Ruptured perineum. — Ruptured perineum is a tear between the rectum and vagina in a mare at the time of foaling and is very objectionable. Some cases are curable by an expert surgi- cal operation. LECTURE LII UNSOUNDNESS {Continued) Examination. — An examination for soundness should be sys- tematic and thorough, although it may be rapidly done. Ex- amination should be made with a horse in the stall and as he backs out, stands at rest, and moves about. It is usually neces- sary to both see and feel and it is not safe to trust the eyes alone. In the stall examine to see whether the horse cribs, weaves or points, or has any stable habit which is objectionable. As he backs out of the stall, he may show peculiar use of the hind legs or imperfect control due to disorders of the nervous sys- tem. Very frequently the iirst intimation of spavin is given as the horse is made to step from side to side, particularly when he steps toward the spavined leg, or an obscure stringhalt may be detected as the horse backs out of the stall or comes ont of the stable. At rest. — Outside the stall the observer should observe the attitude again for a favored limb, dummy, cribber, wind sucker, poor hearing, bad disposition, etc. Beginning in front, examine the ears for hearing, for tumors that may develop at the base, for split ears, etc. In examining the eyes it should be borne in mind that periodic ophthalmic (moon blindness) recurs at intervals and leaves the eye more or less nearly normal between times. The eye may show a weakened, or squinting, or hazy appearance that is suggestive. The nostrils should be examined for ulcers, scars, or dis- charges which would suggest glanders. Dishonest dealers some- times plug the nostril with sponges to prevent the appearance of suspicious discharge. The teeth should be examined for evidences of cribbing shown by the rounding of tlie incisors, for age, and for a condition commonly known as parrot mouth, i.e., overhanging upper teeth, which interferes with pasture feeding. The lips should be examined for evidence of paralysis. The 249 250 VETERINARY STUDIES submaxillary lymph glands under the lower jaw should be ex- amined particularly with reference to glanders. (See Glanders. Lecture XLI.) Foul breath may show diseased tooth or diseased maxillary sinus. The 2)oll should be examined for scars or other evidences of present or previous poll-evil, which is a deep discharging sore like fistulous withers. The withers should be examined for scars, for discharging sores, and other evidences of fistulous withers. The shoulders should be examined for sweeny, sore neck, and, particularly, for so called collar boils. The latter are either flat and broad or more prominent tumors, which will usually subject a horse to sore shoulders when he is put to work. The elbow should be examined for shoe boil ; the knee for scars or what is commonly known as "broken knee," which indicates that the horse is inclined to stumble, and also for knee spavin, a bony enlargement, usually located on the inside. The cannon or shin bones must be examined for splints, and behind them the tendons must be examined for evidences of sprains and other injuries, which are usually indicated by a thickening. Ankles are to be examined for evidences of interfering, and fractures or other injuries of the sesamoid bones and attached ligaments. The pastern is to be examined for ringbones, side- bones, and evidences of the operation known as nerving. In case of doubtful sidebone have the foot lifted and then examine it again. Evidences of nerving are found in scars about mid- way of the pastern on each side and just at the edge of the back tendon. The sides of the back tendons should also be examined just above the ankle for scars, which would suggest another nerv- ing operation. The mere fact that a horse has been nerved, whether going sound at the time of examination or not, is a very serious objection. This operation is not usually resorted to except as a measure of last resort, and it does not in any sense cure the original disease. The feet should be examined for evidences of contraction at the heels, for flatness or convexity of the sole, corns, founder, navicular disease, thrush, and other foot diseases, such as quar- ter and toe cracks, and serious injuries to the crown of the hoof by sharp calks. UNSOUNDNESS 251 In examining: the feet, the shoe should usually be removed and every portion of the sole and frog examined for nail punc- ture. A blacksmith's sage knife is best for the purpose. While passing along the side and flank the breathing should be observed to determine whether it is even and regular, or jerky, suggesting heaves. The flank and lower i)art of the abdomen must be examined for i)0ssible ruptures. Stepping behind the horse compare the two hips for evidences of fracture. A horse so affected is commonly described as being hipped or liiji-shot. Tliis unsoundness is due to fracture of a small piece off the external angle of the ilium. It does not in- terfere seriously with working ability, but produces a very awk- ward appearance and materially lessens value. The /ior/.'.s' must be examined for bog and bone spavins, thor- oughpins, curl)s, and capped hock. The same examination is made of the cannon, ankle, and pastern as for the front limbs. In motion. — The horse should be examined wliile walking and trotting. The movements of the neck and head are studied as he comes toward and passes by the observer, the movements of the limbs being noted as to the height to which they are raised, and the bend of the joints (whether easy and natural or other- wise). The way in which the limb is carried and the foot "lands" upon the ground — whether flat, on the toe, on one side, or on the heel — -is to be noted and considered. As the horse passes from the observer, the movements of the hips and hind legs are noted with a view to detecting lameness in those parts. To bring out diseases of the feet examination in motion on hard road or pavement should be made. Then if there is uncertain lameness, motion in deep mud or in snow should be studied. If such conditions are not available, the horse should be made to step over a wagon tongue or a plank, held up about a foot from the ground, in order to detect or make more prominent possible soreness or lameness in the shoulder or hip. Finally, the horse should be given vigorous exercise on a full stomach ; for instance, a run to a heavy wagon, or a short run uphill, to determine whether the respiration is normal, or in otlier words to test his "wind." While a horse is at rest or at light exercise, it is i)ossible to partially disguise abnormal breath- ing; but severe exercise on a full stomach will usually bring it out. The most common and obvious forms of unsoundness are : 252 VETERINARY STUDIES Bad eyes ; especially cataract ; glanders shown at the nose ; poll- evil, just back of the ears, at the top of the neck ; fistula at the withers ; heaves and roaring, shown in breathing ; splints, along the cannon; injured tendons; farcy sores on limbs or body; ankles bruised from interfering ; sidebones and ringbones at the pastern; navicular disease, corns, founder, cracks in the hoof; fractured hip (hipshot) ; spavin at the hock in front, and curb at the hock behind. Lameness. — A lameness is any irregularity of the gait, re- gardless of cause or degree of severity. Locating the lameness. — It is usually quite easy for any observer to see that an animal is lame, provided the lameness is at all decided, but there are many cases where lameness is so very slight or complicated that it is difficult even for an expert to locate it. Examination may be necessary before, during, and sometimes after exercise. Side. — A very common error is that of locating the lameness on the wrong side. The head and weight of the body in gen- eral, come down most noticeably with the sound limb. For in- stance, a horse which is lame in the left front leg will nod and drop the head, neck and front quarters, as he lands upon the right front leg. Gait. — Some forms of lameness are detected with great dif- ficulty when the animal is walking, but are easily seen when the horse is trotting. It is usually conceded that the latter is the best gait for diagnostic purposes, although the observer should study the movements at both walk and trot. The pacing gait is rather confusing. General examination. — The horse should be examined at rest and when he is unblanketed in the stall. He may "point" or he may uneasily raise and repeatedly shift the same foot, indi- cating the unsound limb and even the location and nature of the trouble. The horse should then be made to step from side to side, and forward and back, then taken out and observed while walking and trotting, coming toward, passing by, and going from the observer, the latter observing carefully the movements of the entire body and the use of each limb. It is especially important to obsei-ve the head and hips in solving the first problem of locating the diseased limb. In case of doubt, circle the animal UNSOUNDNESS 253 both ways ; he may show plain lameness when the diseased limb is on the inside. The horse should be tried on both hard and soft ground and on side hill. If the lameness is in the foot, it is most marked when the animal travels on hard ground. When it is in the shoulder, he is likely to travel with great difficulty in deep mud or in snow, or when stepping over a wagon tongue. When the trouble is in front it should always be borne in mind that the front foot is an especially common seat of lame- ness, whereas in the hind leg, trouble is most common at the hock. Sometimes unusual combinations are confusing. A horse lame in both front or both hind limbs is short and stilty in stride, carrying his feet close to the ground, and backing with dif- ticulty. If in trotting two diagonal limbs are lame, the whole body rises as they land and falls as the sound pair land. If two limbs on the same side are lame there is a peculiar see-sawing of the entire body. Lameness at shoulder, stifle, and hip is indicated by difficulty in bringing the limb forward and there is "swinging leg lame- ness. ' ' A horse affected with shoulder lameness often rests the lame limb on the toe, with the knee flexed and the limb directly be- neath the shoulder. He has a short forward stride, and a swing- ing leg lameness, which is worse when he travels up hill, or in mud, and often shows plainly when turned short. He has great difficulty in backing, and drags the limb. OBSTETRICS LECTURE LIII OBSTETRICS Obstetrics is the science which deals with the birth of young animals. The female organs stndied in obstetrics are: ovaries, Fallopian tubes, vagina, and uterus. Ovaries. — These are two small, more or less flattened, spheri- cal organs, suspended in the front part of the broad ligament (see uterus) in the sublumbar region. Their function is tj develop, mature, and discharge the ovules or eggs. Fallopian tubes. — Two slender tubes con- sisting of mucous, nnisfular, and serous coats, the mucous mem- brane being contin- uous with that of the uterus. They connect the ovaries, one on each side, with the horns of the u t e r u s. The ovules or eggs pass through these tubes on their way to the uterus. Uterus (womb). — The uterus is a muscu- lar sack small in non- pregnant animals and very large in pregnant animals — located partly in the pelvic cavity and partly in the abdominal cavity. Structure. — The uterus consists of three layers or coats: {a) outer or peritoneal; (&) middle, muscular; (c) inner, mucous. The outer (a) is the thin, delicate, glistening membrane, the peritoneum, which lines the entire abdominal cavity and covers with another layer every organ within that cavity. The middle coat (&) is composed of two distinct sets of muscle 254 Fig. 87. — Generative Organs of the Mare. 1, ovaries; 2, Fallopian tubes; 6, horn of uterus intact; 7, horn of uterus laid open; 8, body of uterus; 9, broad ligament; 10, cervix or neck of the uterus; 13, outlet of the ure- thra. OBSTETRICS 255 fibers. The outer fibers extend lengtliwise, and tlie inner ones around the uterus. The muscular coat gives strength and support to the womb and aids in expulsion of the fetus at birth. The inner coat (c) is a mucous membrane and very similar to that which lines the mouth and whole alimentary canal. This coat has especial importance, since it provides for early nourish- ment of the ovum and later develops the maternal placenta or afterbirth which gives the l)ond of union l)ct\vcen the mother and fetus during gen- pregnancy. Shape. — In eral the body of the uterus is cylindrical and divides in front into two branches. Each branch con- nects with a Fallo- pian t u b e a n d through that with the ovary. The body of the uterus narrows behind to a neck which pro- jects into the va- gina except in the sow. The cervix Fig. 88.- -Fetus and Fetal Membranes op the Cow AT Mid-pregnancy, Uterus opened on the right side, exposing fetus and membranes. Note the small, light-colored bodies (cotyledons) which connect uterus and mcndiranes. 8eo also Fig. S9. A, uterus; B, cer- vix (neck of uterus). (neck), body and horns differ greatly in the various domestic animals, e.g. the cervix in the cow is from two to three inches long, very firm and with a tortuous canal. The sow has the body of the uterus short, horns long and the cervix not very distinct, the vagina and uterus being more nearly continuous. The rectum is above the uterus, and the bladder below it. Supports.— The uterus is held in place by four ligaments which are partly folds of the peritoneum. The most important of these are the broad ligaments. These are two wide folds of the peritoneum witli some fibrous and muscular tissue, which are attached to the body of the utcnis and its horns, one on each side and to the sublumbar region above. A third liga- ment is attached al)ove to the rectum, and a fourth below to the 256 VETERINARY STUDIES floor of the pelvis. These four ligaments all give support to the uterus and hold it in position. Openings. — There are three openings into the uterus : one behind, opening into the vagina, i.e. the cervical canal through the cervix ; and two in front, for the Fallopian tubes. Function. — The function of the uterus is to receive and nour- ish the ovum and mature it after it has been fertilized. The ovum attaches to the uterine wall and three covering and supporting membranes are developed around it. These in order from without in are the chorion, allan- tois and ammion. Here the fetus develops, re- ceiving oxygen and food materials from the ma- ternal uterine walls, through the surroimd- ing placental mem- branes. There is no direct circulation from mother to fetus. In the cow, sheep, and goat, contact be- tween the mother 's uterus and the chorion is by about 60 to 100 large, rounded button-like bodies called cotyledons, developed from the mucous membranes of the uterus. Over these fit cap-like bodies from the fetal chorion. The mare has a very different relation between fetus and uterus. Her uterine mucous membrane is provided with a very large number of tiny pockets into which fit minute capillary tufts, making a practically continuous contact between uterus and chorion. Vagina. — This is a membranous tube which contains much muscular tissue in its walls. Structure. — There are three coats: (a) outer, of loose con- nective tissue ; (6) middle, muscular; (c) inner, mucous. Close to the cervix, the external surface is covered also by the peri- toneum. Location. — The vagina is located in the pelvis between the rectum above and the floor of the pelvis below. It is capable of great dilation to allow the passage of the young at birth. Be- B ^B ^B 1 ^£ ^^s ^^w 1 m ^s ^B 1 |b ^^^S ^^^K ■ jjg ^^M 1^^^ 1 Fig. 89. — Bovine Cotyledons. A, pedicle of uterine cotyledon; B, B, uter- ine cotyledon; D, fetal cotyledon; E, fetal membrane. OBSTETRICS 257 tween the uterus and vagina the connection or common open- ing is through the neck of the uterus, properly the cervix. At this point the uterus narrows greatly and is composed of firmer tissue, especially in the cow. As the time for delivery ap- proaches this narrow canal is dilated until the opening is large enough for the young animal to pass through. Normal period of gestation. — This varies from two years in the elephant to 30 days in the rabbit. The cow carries young about 283 days; mare, 345 days; sow, 119 days; ewe, 149 days. All these may vary greatly. Old animals usually carry longer than young. Accidents op Pregnancy The most serious accidents of pregnancy are : abortion, reten- tion of the fetus, and volvulus (twist in and near the neck of the uterus). Abortion. — For the purpose of this lesson, abortion may be defined as any premature birth. Abortions are either sporadic or infectious, usually the latter. Sporadic abortions may be due to a great variety of condi- tions; e.g., death of very weak embryos; strong medicines, espe- cially purgatives; mechanical injuries; sudden and unaccus- tomed exercise ; extreme nervous excitement ; diseases accom- panied by cough or severe pain or high fever ; disease of the uterus and lack of constitutional vigor in either sire or dam. Infectious abortion is an ^exceedingly serious disease. The actual abortion should be considered as merely one of several serious symptoms of the disease. See "General results." It is due to contagium ; i.e. to the action of living germs upon the uterus, fetus, and placental membranes. Infectious abortion, unlike hog cholera, does not spread rap- idly through a herd. Cases usually come at irregular intervals throughout the season until a large percentage of the herd may have aborted. See next Lecture. Symptoms. — Symptoms of approaching abortion depend on the stage of pregnancy, and are frequeritly obscure or even lacking if the abortion occurs very early. Sometimes there is a discharge from the vagina aiul its mucous meml)rane may be dee'^ily congested. Slight labor pains sometimes appear several hours before the fetus is expelled and before the sac is rup- tured. Occasionally tlic animal may be noticed moving around 'v 258 VETERINARY STUDIES uneasily. Ligaments at the tail head on each side relax and drop. The udder develops prematurely, especially noticed in heifers. General results of abortion. — The afterbirth is frequently retained and septicemia ("blood poisoning") may ensue in the absence of skillful treatment. Garget may appear, which seems to be associated with the condition of the uterus, probably by transfer of infection from the discharge. The appetite may be impaired or lost. The patient may lose flesh or she may come in heat frequently, but remain barren. Sterility, retention of afterbirth, white scours in young calves, calf pneumonia, calves born weak with tendency to diarrhea may all be features of infectious abortion. LECTURE LIV OBSTETRICS— Continued Infectious Ahortion In many respects, infections abortion is the most serious dis- ease confronting the American breeder. Those responsible for its control are confronted with many and serious difficulties. The disease is insidious, the period of incubation being rather long. There is no satisfactory means of individual diagnosis and prevention is uncertain. Management of an infected herd is tedious, expensive, and results often unreliable. Causes. — Infectious abortion is due to living microorganisms, usually bacteria. It is evident that several different germs are capable of causing this trouble, and if this be true, then we do not have a specific disease due to one specific germ. It is most common in cattle at five to seven months, but may occur at any time after a few weeks of pregnancy. Cattle, horses, sheep, and swine are all subject to an infectious abortion, due to several different microorganisms. The virus generally accepted as being chiefly responsible for abortion in cattle and swine (the Bacillus of Bang) appears to be the same, although the disease apparently does not spread from the one class of stock to the other. In mares and ewes, however, the viruses are different. The student should remember that the act of abortion is only one of several disastrous symptoms, as taught in the preceding Lecture, and not in itself a complete disease. Abortion in horses, swine, and sheep is less common and less serious than in cattle at present, and this Lecture will treat chiefl}" of infectious abortion in cattle. It is evident that infectious abortion may be spread in many ways. It is most easily introduced by the purchase of an in- fected pregnant cow from a herd in which the disease has pre- vailed. A cow may abort one or more times, then become more or less immune and subsequently carry calves to full term, but remain infectious for an indefinite period, and thus prove a 259 260 VETERINARY STUDIES very serious, because unsuspected, source of spread. Under natural conditions, infection may occur by way of the respira- tory, digestive, or genital tract in breeding. The afterbirth, discharges from the womb and vagina, and manure of abortion calves are all probably infectious. Results. — A serious percentage of cows which abort subse- quently become sterile. Most cows do not abort more than twice and thereafter may become either regular breeders, or shy breeders or sterile, or they may become immune ' ' carriers, ' ' i.e. raise calves but remain infectious. Contamination with the virus of abortion may result in abortion, or in a birth at or near full term, with the calf weak and predisposed to diarrhea. Cows which abort are likely to retain placenta and be unthrifty for a long time. Some contract infection of the udder probably from vaginal discharge, terminating in serious case of garget; or there may be a general septicemia or blood poisoning. Diagnosis. — ^We have first the history of an unusual number of cows in a herd dropping their calves prematurely. Fre- quently the vaginal discharge wdiich accompanies abortion is dirty in appearance with shreds of tissue and a foul odor. The mucous membrane of the vagina may become congested and the lips of the vulva swollen several days before abortion occurs. A coming abortion in heifers is often indicated by marked pre- mature development of the udder, and the ligaments at the tail head on each side relax and drop. Older cows are apt to abort without any warning. There are two serum tests which give useful, but limited in- formation. In a general herd test they furnish information as to the general condition of the herd with reference to the dis- ease. But they do not tell whether a certain cow has aborted or will abort or is a spreader of the disease. Prevention. — It is necessary to bear in mind the probable cause of this disease and the common methods of dissemination. A farmer owning a healthy herd should not purchase cattle of breeding age from a herd in which this disease has prevailed within three years. He is safer in any case if he buys unbred heifers or mature cows that are heavy springers with good breeding history. He should not do public service with a herd bull where there is possibility of contamination, nor should he use a neighbor's bull if it is possibly contaminated with this infection. It is also safer policy for the breeder to raise his OBSTETRICS 261 own females as far as possible and purchase young males that have not been used. Mana-gement of an aborting herd. — Abortion should not be allowed to occur in the herd stable if it can be avoided. The calf and afterbirth should be buried deeply or, better still, burned. Floors and partitions and other contaminated surfaces should be carefully cleaned and disinfected. In case the calf is mature enough to survive, its manure should be treated as though it were certainly infectious. Some outbreaks of what seems to be infectious abortion are apparently gotten rid of very easily under a treatment which to an experienced veterinarian or bacteriologist would be absurd; but as a rule very painstaking work, long continued, is essential to any assurance of success. An owner should not undertake the treatment of a considerable number of animals unless they are sufficiently valuable to make it worth while, and he realizes that he has a hard task ahead of him. Sell for slaughter females that have ever been bred and which are not valuable enough to justify the additional work and expense of treatment. Cows that have aborted should be sold for slaughter only; but it is not asually advisable to sell good cows merely because they have aborted. Medical treatment is now generally discarded as ineffective. There is no reliable cure. Various vaccines and serums are on the market and are well advertised; but they are of doubtful value. There is a living virus vaccine which appears capable of harm by dissemination of the disease. There is also a killed culture vaccine which appears to have little protective value. Neither is advised as yet as a preventive of abortion. It frequently happens in affected herds that valuable cows abort and then remain sterile. Others are infected and remain sterile without known abortion. Many of these choice cows can be cured of their sterility by expert veterinary treatment. AA'hen a cow has aborted well along in pregnancy, the after- birth should be removed as soon as it will come away easily. Cows that have aborted should not be bred until the discharge has ceased for at least a month and the generative organs are normal again. Males should be used with caution. For cows that have never aborted, use a bull tliat has had no chance for infection, the 262 VETERINARY STUDIES bull's sheath to be disinfected internally before and after each service. If possible, use a different bull for cows that have aborted, he also to be disinfected before and after service, but with a different tubing and nozzle. In any herd where there is danger of this infection, calves should be born in clean and recently disinfected stalls and from clean and externally disinfected dams. Treat the stump of the calf's navel cord with tincture of iodin in a cup or wide mouth bottle : This is easier to do with the calf on his feet. Iodin treatment is to be repeated until the cord is dry and hard. Soak it several minutes at each treat- ment. Equal parts of alum and boraeic acid may be dusted freely over the cord after the iodin treatment. It is important to remember that a calf may be infected early in life through milk from dam or nurse cow, the virus coming from the udder in the milk. Or the young calf may be infected from external contamination of the teat and udder by vaginal discharge. It is safer, therefore, in an aborting herd to wean the calf early and raise it on pasteurized, or even boiled, milk. Tliere is then less risk of calf scours and calf pneumonia, which are common in such herds. Calf-scours serum appears to give good results as a preven- tive and should be given to all calves in affected herds, as soon as possible after birth, in addition to the sanitary precautions already advised. Internal disinfection as used here means injection into the vagina, not uterus, for females and into the sheath for males. External disinfection for cows means surface in general, but especiall}' around and under the tail and between the thighs ; for bulls, the outside of the sheath, especially around the opening. For internal disinf ectioii use one half per cent solution of Lugol's iodin; or, for simple cleansing, common salt, a table- spoonful to the gallon of water. A container, a funnel, and a few feet of i/^-inch rubber tubing with a short smooth nozzle of some kind is all that is necessary for apparatus. For treating a large number of cows, a simple container for a gravity appa- ratus is very convenient and cheap. This may be made from a large galvanized iron pail with a stopcock at the bottom. An old-fashioned "shotgun" milk can is an ideal container, since it is already fitted with stopcock at the bottom and has a glass OBSTETRICS 263 gauge at the side where the amount given each animal may be easily read off as the fluid lowers in the can. The container may be very conveniently held by an ordinary snap sliding on an overhead wire extending across the stable back of the cows. Stables. — Frequent cleaning and free use of stable disinfec- tants is necessary for mangers, partitions, floors, etc., with plenty of lime in the gutter. Manure should be removed and used so that it cannot carry infection to pregnant cows. Feed for breeding females must not be contaminated by discharges from aborting cows, or by manure from calves born of aborting cows. For disinfection of the cow stable, litter should be cleaned out of the mangers and stalls; walls, partition, floors, etc., should be thoroughly scrubbed using plenty of water and then be disinfected by means of corrosive sublimate, 1 to 1000 in water, or copper sulphate, 5 oz. to a gallon of water, or, by corrosive sublimate in fresh whitewash in the proportion of 1 lb. corrosive sublimate to 1000 lbs. of water (125 gallons). :\Iany bulletins on abortion have been issued by state experi- ment stations and the Federal Bureau of Animal Industry. These may be easily secured and should be consulted for details of herd management and individual treatment. This work should be under the supervision of a competent veterinarian who has given special study to the problems involved. LECTURE LV OBSTETRICS (Continued) Accidents of Pregnancy Accidents of pregnancy are nearly all serious and should be handled by a veterinarian whenever possible. A neighbor's meddling has killed many a fine cow and mare that could have been saved. Retention of the fetus. — This trouble is most common in cows. The period of retention may vary from normal up to years. A fetus may be dead and mummified, or it may decom- pose. Aged mares sometimes carry beyond the normal period for delivery and then give normal birth. Sijmptoms. — The mother may show labor pains at normal time and all other symptoms of parturition may be present. The symptoms soon disappear and the cow goes on as if non- pregnant, but does not come in heat. Causes. — Retention of the fetus is due to such causes as par- tial paralysis of the uterus, excessive adhesions between fetus and uterus, deformed pelvis, and torsion of uterus. Treatment. — At the normal period of delivery with the cow in labor and not progressing properly, the veterinarian should be called, to dilate the cervix and force delivery if indications justify such radical procedure. This is very difficult in the cow and easier in the mare. If the cow has gone safely past this period, then fatten and sell her for beef. Volvulus (twist). — A twist sometimes occurs in and near the neck of the uterus and makes delivery exceedingly difficult. It is much more common in the cow than in the mare, and usually occurs near the termination of pregnancy. Symptmns. — Labor pains and the normal symptoms of de- livery appear at the usual time. If not relieved serious illness may follow. The cow becomes anxious and restless, her respira- tion is hurried. She shows abdominal discomfort, and if not relieved will probably die. On examination, a spiral twist of 264 OBSTETRICS 265 the uterus is easily recofjnized unless it be far forward and out of reach — which sometimes occurs. Cause.— YoUulns may be caused by the patient slipping or falling, and especially if the cow or mare rolls over, late in the period of pregnancy. Some authors think it may be due to active and unusual movements of the fetus. Treatment.— U the twist is slight, the operator may be able to reduce it by introducing the hand into the uterus, grasping some portion of the fetus, and causing the uterus to unwind by a strong, twisting motion. Even when it is possible to intro- duce the hand, treatment is apt to be a slow and difficult task. It is necessary to proceed slowly as the tissues relax. If the case is at all difficult, call your veterinarian promptly. Some- times it is necessary to throw the cow or mare, then introduce the hand, grasp firmly one or more limbs of the fetus, and have the cow rolled in the opposite direction from the twist, holding firmly to the fetus meanwhile. If the operator can succeed in getting his hand into the uterus, and especially if he can get one or more fetal limbs through the neck of the uterus, the twist often may be reduced. ]Many of these cases, however, are exceedingly difficult or incurable. Accidents of Parturition The most common accidents are: (a) Infection; and inflam- mation of the uterus (metritis); (&) inversion of the uterus; (c) tear in the vagina; followed by infection and vaginitis; (d) retention of fetal membranes; (e) hemorrhage; (/) mam- mitis (garget). Metritis.— Inflammation of the uterus is a very serious dis- order and apt to result in death from septic metritis or peri- tonitis. The symptoms usually appear within one to four days, with chill, high fever, thirst, abdominal pain, and cold extremi- ties — ears, horns, etc.— straining, vaginal discharge and swollen, discolored vulva. There is frequently posterior pa- ralysis. Pressure in the right flank is very painful. Inversion of the uterus. — This disorder is most common in the cow, and may be partial or complete. There may also be partial eversion of the bladder and vagina. It may be due to excessive force used in aiding delivery, or to failure of the uterus to contract after delivery. 266 VETERINARY STUDIES Treatment. — Cleanse the protruding uterus thoroughly with hot water and invert it over the hand and arm. Be careful to smooth out each fold and leave the uterus in a natural posi- tion. If the organ is greatly swollen and heavy, bathe it in cold astringent solutions, like strong alum water, until the size is sufficiently reduced to permit replacement. A clean, com- mon washtub is very convenient for bathing the soiled and swollen uterus. Bandaging very firmly with a wide roller of muslin forces out much of the blood, reduces the bulk, and allows handling of the uterus without injury. The bandage should be wide, and be rolled from both ends. To put on the bandage, begin with the middle of the bandage at the end of the uterus and carry the ends around in opposite directions, pulling firmly all the time so as to force the blood back into the general circulation. In very troublesome cases it may be advisable to first throw a cow carefully, then hoist her hind parts by pulleys and ropes until only the shoulders and neck rest upon the floor. The rope should be attached by hopples or otherwise just above the ankles, and suitable provision made so as to avoid injury to the skin and underlying parts. A good hopple strap will usually do very well. Ordinary rope could be used with several thick- nesses of heavy cloth or a flat pad of oakum inside of the rope to protect the skin. In this position the uterus of a very troublesome case may usually be replaced easily, and no harm is done to the cow if she is carefully handled. After replacing, it is sometimes advisable to pack the uterus with cotton and close the outlet by means of sutures through the vulva, or to put on a rope truss. Finally give the cow 3 oz. tincture of opium and 2 oz. bromid of potassium in i/^ pint of sirup. Give a mare two thirds of this dose and the ewe one eighth. Repeat the dose in three hours if the animal is still straining. If necessary, apply rope truss as shown in classroom. Tear or bruise in vagina. — A vagina may be torn above or below by excessive size of the fetus, by faulty position of the fetus, or by excessive force used in delivery. Infection and inflammation (vaginitis) then follow. This is indicated by unusual swelling of the vulva with dark and discharging mu- cous membrane. This discharge soon has foul odor. Slight cases usually make prompt recovery under hot water irrigation or OBSTETRICS 267 fomentation. Tears and severe bruises must have veterinary service. This calls for immediate operation by a veterinarian, and the injury is much more dangerous for the mare than for the cow. Retention of the placenta (afterbirth) .—This trouble is most common in cows, but is less serious for cows than for mares. It is caused by unusual adhesions between the placenta and the womb, imprisonment of the placental tufts in the corresponding cavities of maternal cotyledons and by a mild inflammation due to infection, often from infectious abortion. There is normally a short period of exhaustion following delivery. After this period the uterus should recover its nor- mal tone and expel the afterbirth and accompanying fluids. Note the order of development : infection, inflammation with accompam'ing swelling, and then adhesion. Treatment. — For the mare the placenta should usually be re- moved within twelve hours if it fails to come away naturally. If the cow's afterbirth can be removed easily and without hemorrhage, then the sooner it is removed the better. Everything in this work must be done carefully and with a view to cleanliness. Ifirst, irrigate the vagina with an antisep- tic, e.g. one half per cent Lugol's iodin, and disinfect the sur- rounding external parts. As nearly as possible the entire placenta should be removed by introducing an oiled hand into the uterus, gently separating the placenta from its uterine adhesions, and pulling with the other hand outside. If a cow's afterbirth does not come away easily and com- pletely and there be no urgent reason for removal, then treat- ment should be directed against extension of infection. A good authority recommends iodoform and boracic acid, equal parts, and suggests that this may be put in a capsule and the capsule either left to dissolve in the uterus or opened and the powder scattered in the uterus by hand. The purpose of this treatment is, of course, to check the development of infec- tive organisms. The patient should be examined from time to time, and it will usually be found after awhile that the afterbirth has been released and will come away easily. In some cases of retained afterbirth there develops a rapid necrosis (death) of the ma- ternal cotyledons, in which case the cotyledons themselves may 268 VETERINARY STUDIES come away with the afterbirth and their removal cause no seri- ous harm. Hemorrhage. — This is rare in the lower animals. It is de- noted by rapidly increasing paleness around the eyes and in the mouth and by quick, feeble pulse. Blood may not appear on the outside, and yet the bleeding be "extensive. Give 3 oz. f. e. ergot at once, in 4 oz. sirup, and then give 1 oz. ergot in 2 oz. sirup every hour if necessary, up to a limit of six doses; meantime pour ice water over the back and loins. LECTURE LVI DISORDERS OF THE UDDER Garget (Mammitis) Mammitis is an inflammation of the gland tissue and other structures composing the udder. Some congestion and harden- ing of the udder is probably normal at about the time of par- turition. Causes. — Garget (mammitis or mastitis) is usually caused directly by germ infection or injury, aided by infection. Germs probably gain entrance in many cases through the milk ducts of the teats. There is great variation in the severity of these cases. Some cases of garget are very mild, and some lead to rapid loss of the udder. Many cases of garget are the result of infection through the teat from retained afterbirth, or from some purulent discharge from the vagina. The infection from a retained afterbirth or from the vaginal discharge becomes smeared upon the teat-, bacteria gain entrance into the milk canal, where they find favorable conditions for multiplication and rapid extension up the milk canal into the udder. Some cases receive their infec- tion from the hands of milkers who have milked other cows which have such infectious material upon the teats or the udder. In other cases the infection may have been carried into the milk duct by milk tubes. Many preventable causes contribute to garget, e.g. excessively high feeding, cold cement floors, high door sills and low udders, washing followed by chilling, etc. Symptoms. — The symptoms of garget are the usual symp- toms of inflammation in any soft organ: i.e., pain, heat, redness, and swelling. This is one of the most easily recognized diseases of live stock. Results. — Garget usually leaves a damaged udder. In some cases the damage may be extreme and in others slight ; but it is probable that few cases are ever completely restored to normal. 269 270 VETERINARY STUDIES The injury to the milk-gland structure includes various de- generations, connective tissue hardening and permanent enlarge- ment, abscess, or even gangrene. Development of gangrene may be detected by noting that the part which has previously been hot and tender becomes cold, dark in color, and insensitive. Prevention. — Cows that are wisely fed seem much less liable to udder troubles at the time of calving. Heavy milkers espe- cially should be carefully fed during the last period of preg- nancy. The food should be laxative in character, and this same method of feeding should be continued until about the fourth day after calving, when the grain ration may be gradually increased, the cow being put on feed very gradually for several days. In case of a valuable cow that has just calved, it is well to disinfect the udder and teat with 1 to 1000 bichlorid in water, which may be washed off with water. If possible, this disin- fection should be given before any milk is drawn after calving, and should be kept up for a week in the ease of a valuable cow. It seems that the cow's udder is most liable to this trouble dur- ing the first week or so after calving. Later there does not seem to be so much danger of garget. Milk tubes do very much more harm than good as a rule, and should never be used except when absolutely necessary, and then only after thorough disinfection of the teat and boiling of the tube. The latter must not be handled in any way to infect the portion which is to enter the teat. Care should be exercised not to milk a cow with hands that have been contami- nated from purulent discharges of any kind or with any kind of infectious material. A cow with garget should always be milked last. Milkers should clean their hands thoroughly for the sake of simple cleanliness and pure milk, if for no other reason, and in addition for the very good reason that they are then not liable to carry infection which may cause garget in the udders of valu- able cows. Floors, door-sills, etc., should be as little likely as possible to injure udders. A cow with very long udder should be so placed in the stable as to avoid injury from tread by another cow. Treatment. — The diet should be light and laxative. Light feeding during the last few weeks before calving is a good preventive measure in any case. DISORDERS OF THE UDDER 271 If intcriial, or vaccine, treatment of any kind is needed it should be given— or at least directed— by a veterinarian. In most cases the owner can safely give nitrate of potash (salt- peter), 2 ounces at a dose, with 1/2 pound Epsom salts, three times a day, each dose dissolved in a quart of water. For external treatment of the udder, apply hot water freely for long periods of time ; e.g. twice a day 2 or more hours at each treatment. The water should be used as hot as it can be comfortably handled— it is easy to scald an udder— and should be used very freely. This hot-water treatment may be applied to good advantage by putting a sling around the cow's body under the udder and in front of the hips to support the udder. Four holes may be cut for the teats, and woollen cloths packed around the udder to hold the heat and moisture. The hot water can then be poured in from above or be thrown against the pack- ing from below by means of a small dipper. The object is to treat the udder with moist heat for a long period of time. After each water treatment rub the udder dry and apply a light dressing of olive oil. Long-continued, moderate rubbing and handling of the udder is beneficial. This is best accom- plished by first milking dry and then a combined rubbing and gentle kneading action with the hands. This massage, if not unreasonably severe, is helpful, and should be given freely sev- eral times a day and for 15 minutes or more at each treat- ment. Udder Diseases and Accidents Injuries. — Udders and teats are often injured by barbed wire, for example, or by being tread upon in the stable by a cow in the next stall; and these injuries require careful treatment usually by a veterinarian. Treatment. — In general such wounds should be trimmed, well soaked in a mild, hot antiseptic, like hot saturated boracic acid solution, and then covered with an antiseptic powder. In case but little tissue has been destroyed, it may be well to partly or wholly close the wound and cover a generous portion of the teat with surgeons' adhesive tape. Tears into the milk duct require skillful surgical treatment, and the teat may often be saved in good shape. The owner should not insert a milk tube except as a last resort. It is often safer to trust to long con- 272 VETERLNARY STUDIES tinued hot mild antiseptic treatment and gentle massage to reduce the swelling and re-open the duct. Fistula. — This is a small opening in the side of the teat, which opening connects with the milk duct and usually leaks milk at least during milking. It is just an unclosed portion of an old wound. Treatment. — When the cow is dry, sterilize the teat with tinc- ture of iodine, then with a very slender pointed and sharp knife that has been boiled and carefully handled to avoid infection, rim out the old skin edge, so as to get a fresh raw edge for healing; or sear very slightly and superficially in the fistula with a hot wire. After this treatment, sterilize the wound and teat again with the iodine, and bandage it with adhesive tape, covering plenty of the teat. This must not be tight enough to interfere with the circulation and should usually be left in place several days. Teat obstruction. — This may be due to a stricture or narrow- ing of the canal as the result of an injury. Many cases are due to small growths of various forms, wliich result from a mild infection. They often form while the cow is dry and are found at the next milking. Many of these cases can be cured by a veterinarian's skillful surgical operation. Warts. — In case warts cause trouble, they may be removed in various ways, as by cutting them off with sharp shears, taking a bit of normal skin all around the wart, or by tying them off by a stout thread close to the teat. Hard milker. — Otherwise choice cows are often sold or killed, because they are hard milkers. The difficulty in these cases is usually superficial, the end of the milk duct opening being too small. In many cases this can be cured by careful dilation with a slender cone of smooth hard wood or metal. Sterilize the teat with tincture of iodine. Boil the dilator ten minutes and handle in a way that avoids contamination. Insert the dilator carefully, and leave in place between milkings. Caution is necessary to avoid over-dilation and consequent leak- age. The veterinarian uses special dilators or makes a small cross-shaped incision in the outlet by a special instrument. Cowpox. — Cowpox is a contagious disease and apparently due to a filterable virus which is very closely related to or identical with human smallpox virus. Sheep-pox is probably an entirely different affection. This trouble may be brought into a herd by DISORDERS OP THE UDDER 273 recently vaccinated persons. Thereafter, the disease is spread in the herd chiefly by the hands of milkers, but may be transferred from cow to cow by other means. The period of incubation is from four to seven days. Then there is a little fever and mild general symptoms of slight ill- ness. There soon appear a few nodules on the udder and teats, the size of a pea or smaller. In a day or two these change to vesicles (blisters) which contain a thin, clear fluid. At eight or ten days the centers of the vesicles become depressed and the contents become purident (pus). A dry scab gradually forms and falls, leaving the typical pitted scar. The sores heal nicely unless injured in milking. Small, slow healing ulcers may be caused in this way. Treatment. — Little treatment is necessary beyond very careful milking, unless the vesicles are ruptured and the raw surfaces injured, e.g., in milking. Careful handling and a little vaseline or lanoline are then needed. LECTURE LVII DIFFICULT PARTURITION (DYSTOKIA) Nature's plan. — ^When the delivery occurs according to nature's evident plan, the ligaments of the pelvis relax; the water bag appears through the neck of the uterus and finally outside the vagina; the neck and vagina gradually dilate to accommodate the fetus, which presents first the apex of a wedge or cone. Normal presentations. — We recognize two normal presenta- tions, viz., the anterior, in which the two front feet and the nose appear with the fetus resting upon its sternum, and the posterior, in which the two hind legs and tail appear with the fetus resting on the sternum. Variations from these cause difficulty in delivery. Cause. — The cause of difficult parturition may lie with either the mother or the fetus, though more commonly with the latter. If the fault lies with the mother, it is usually because of premature delivery; extreme narrowness and closeness of the pelvic outlet; volvulus; deformities of the pelvis (sometimes fracture); tumors within the pelvis; or induration, hardening, of the uterine neck. Sometimes the trouble is due to excessive accumulations of fat within the pelvis. If the difficulty lies with the fetus, it is because of faulty presentations, excessive size, monstrosities, or deformities. Common faulty presentations. — Faulty anterior presentations may be : head, or head and neck doubled back ; two feet, or feet and legs back ; or the neck and one front limb back ; or the neck and both front limbs back. Faulty posterior presentation may be: one limb back and doubled at the hock or stifle ; or both limbs back with one flexed at each of these points, or both flexed at the same joint, which may be either hock or stifle. Various other false presentations may occur. 274 DIFFICULT PARTURITION (DYSTOKIA) 275 Fig. 90. — Presentations. (B. A. I.) A and B, normal; C, D, E, F, common abnormal presentations. 276 VETERINARY STUDIES Assistance What may be needed. — There is probably no trouble with farm stock where trained and experienced veterinary assistance is more urgently needed. Call your veterinarian promptly, if one is available. Do not let all the neighl)ors try it first and ruin all chances for the veterinarian's success — especially with mares. If no competent veterinarian is available, then the owner must do the best he can for himself, or with the aid of a careful and experienced neighbor. Plenty of bland oil, e.g. linseed, may be required; two small window cords with smooth loops in one end of each loop to loop around limbs ; two similar ropes with short, sharp hooks in end to hook in underjaw or ej^e socket or leg ; a pair of small combination pulleys, possibly an embryotomy knife, large trocar and cannula, some antiseptic — e.g. creolin — to be used in 4 per cent solution for hands, instruments, and ropes. These should be kept on hand and ready. Suggestions. — Do not interfere until the water bag has rup- tured, unless labor pains have continued for several hours and the water bag does not appear. Then examine by rectum and note location of fetus. Possibly it may not yet be even in posi- tion for delivery. In that case if you cannot have veterinary service leave the cow alone and await normal delivery. Examine by rectum every twelve hours or so to note progress. If the cow is strong and the calf alive it may be born naturally a day or two after the first false labor pains. However, if the first examination by rectum shows the calf well advanced and presenting for delivery and no progress being made then examine by vagina and cervix. There may be a vohiilus. See Volvulus in preceding lessons. If the water bag ruptures, in a natural way, and the head, for example, should present without the feet, or the head and one foot, or if one hind foot presents and not the other, or any evidently faulty presentation occurs, then it is time to call your veterinarian, and plan for assistance. If you cannot have expert help then clean and oil the arm and examine carefully to learn the cause of trouble and position of fetus. Then decide what you will do and how. The rectum should also be examined as the hand goes into the vagina, and if distended should also be emptied. DIFFICULT PARTURITION (DYSTOKIA) 277 The patient should stand or lie with head do^vnhill. It is much easier to operate with the patient standing. Occasionally it is of great advantage to have the patient on one side or the other or on her back for a time so as to place the missing part on the upper side. Be patient and not in too great haste. When missing members are secured and all is ready to pull, pour plenty of oil, or, in the absence of oil, warm water, into the uterus and vagina by means of a funnel and rubber tubing. The parts that will offer friction are probably dry by this time, and should be freely oiled or moistened. Clean, non-irritating oil is better. It is frequently necessary to shove the fetus forward into the uterus in order to secure and straighten some missing parts. Tearing the mother is an accident that must be carefully avoided on account of probable blood poisoning (septic infection). "When one part presents, and others are to be secured, or when one has been secured and it is desirable to return it into the uterus to secure another part, make sure of progress gained by attaching a rope to the part secured. If the patient cannot be made to stand, have her on the side opposite the missing part, which thus comes on top. "Work between labor pains, and, when all ready to pull, the assistance should be given moderately and while the mother is straining. Great force is seldom justified either by necessity or by results. Dropsies. — Sometimes the retarded delivery is due to large accumulations of fluid in the brain cavity (hydrocephalus) of the fetus or within the abdominal cavity (ascites), or to a general accumulation of fluids or gas beneath the skin in the connective tissue and also in the abdominal cavity (general dropsy). In these eases the difficulty may be overcome by tapping the brain and squeezing the soft bones together, or tapping the abdominal cavity and allowing the fluid to escape. A large trocar attached to rubber tubing is convenient for this operation. Gaseous distention. — Difficulty in delivery may be due to an excessive accumulation of gases within the body of a dead and decaying fetus, and the obvious treatment is to tap with trocar or knife and allow gas to escape. Embryotomy. — If it becomes necessary to open the fetal body or remove one or more of the fetal limbs, and veterinary help is not available, the operator must know that these are difficult operations and observe certain precautions. 278 VETERINARY STUDIES Beware of injuring the maternal parts; be patient and work slowly. In case of twins, both presenting at the same time, force one back into the uterus and deliver one at a time. Avoid all un- necessary dissections, which are usually very tedious, exhausting to the operator, and mother as well. Always save the skin, leaving enough to cover the bones and rough parts of the fetus, and to pull on. Removing a fore linib. — Take the limb that is presenting, attach cord and draw out, as far as possible ; slit the skin from as near the top of the scapula as possible to the knee or pastern by means of an embryotomy knife, and dissect the skin loose from the limb, largely by fingers or with the aid of a thin bladed case knife wdth a square end ; then cut last the skin around the knee or pastern. Next cut the muscles between the limb and the sternum. By twisting and pulling at the same time, the limb can then be removed entire, leaving the skin attached to the shoulder. Do the dissecting with one hand, while the other pulls on the skin outside. The skin gives an object to pull by, and protects the parts of the mother from bones. It also keeps the soft parts of the fetus from rolling up as an obstruction when pressed against the parts of the mother. Removing the head. — If the head can be brought outside the vulva, and there is good reason for removing it (which is not often), cut the skin around the neck, back of the ears, and dissect the skin loose from the muscles by the hand or by a thin bladed case knife with square end, using a knife to cut the connective tissue bands that interfere, as far as the operator can reach. Then cut the cord on top of the neck, the cord that supports the head, and also the muscles around the vertebra?. Strong pulling and twisting on the head will usually bring away head and neck, leaving a- quantity of skin to cover remaining vertebra? and to assist in pulling. Removal of the hind limbs. — This is done on the same general principle as for the fore limb. Supposing the limb is present- ing, cut across the pelvic articulation of the limb on the inside so as to sever the ligament which holds the femur strongly to the pelvis. Slit the skin from this point to the hock or pastern according to the case. Dissect the skin loose from the limb, as directed for the fore limb. Then by strong pulling and twisting the limb can be torn loose at this joint. DIFFICULT PARTURITION (DYSTOKIA) 279 It is not always necessary to remove both liind legs. "With one out of the way the other can sometimes be straightened or the body of the fetus removed with the other straightened for- ward in the uterus. The soft organs may often be removed from the body of the fetus to advantage, and then delivery be accomplished easily. In some cases it is sufficient, and easier, to disarticulate at the hock instead of at the pelvis. Caesarian section.— Removal of the fetus through the flank or median line of the belly is done sometimes, but only as a last resort, more commonly and successfully done with cows and sows than mares. This should only be attempted by an expert, unless the plan is to save only the fetus. In the latter ease the work must be done very rapidly. This operation is often performed on sows and is reasonably safe for them. MEDICINES LECTURE LVIII COMMON MEDICINES Common measurements: A dime weighs about 40 grains, a nickel 80, a quarter 100, a half dollar 200, a dollar 400 grains. One half dollar and a dime, e.g., would weigh about half an ounce or a dollar and a nickel would weigh approximately an ounce. Teaspoon holds about 1 fluid dram (Vg oz.). Tablespoon holds about 4 drams (14 oz.). Dessert spoon holds about 3 drams. Teacup holds about 6 oz. Giving medicines. — Internal medicines may be given to do- mestic animals in the form of liquid drench, gelatine capsule ball, or dry powder ; or may be mixed with honey or molasses and smeared on the tongue. Some medicines are given under the skin by hypodermic syringe and some by injection into a vein. In giving a drench, remember that a horse's mouth and throat are very sensitive and more easily injured or irritated than the human. Taste the medicine before giving it, if there is doubt about its being too strong. Powders should be finely pul- verized, and must not be caustic or irritating. Balls should be in the shape of a cylinder about 2 inches long and i/o to % of an inch in diameter. They should be wrapped in thin paper and oiled. They must be reasonably soft and pliable, and the horse should be offered water immediately after swallowing them. Drenching. — In giving a drench the patient's head must not be held too high, the face should be nearly horizontal, with the nose just a little higher. If the head is too high swallowing is difficult. The operator must not be in a hurry. The medicine should be given in small quantities on top of the tongue, as far back in the mouth as possible, and the horse should be given plenty of time to swallow. If the horse is obstinate about swal- lowing, pour a tablespoonful of water into the nose after medi- 280 COMMON MEDICINES 281 cine is poured into the mouth. ]\Iedicines should not be given through the nose because of danger of choking, and of causing pneumonia. For supporting the head to give a drench, a rope may be tied to the noseband of halter and thrown over the beam — never tied, but held by an assistant. Bet- ter still, a cloth loop may be passed around the upper jaw back of the front teeth and through the nose- band of the halter in such way that it cannot slip off. This cloth loop is fastened to the overhead rope, which should be held — not tied. Medicines may be given when the patient is lying down, but the oper- ator must be careful not to pour out any medicine when the patient is about to struggle lest choking occur. Plenty of time should be taken. A bottle of rubber or horn, or a dose syringe, is much pref- erable to a glass bottle, which may break readily, and cut the mouth. Cathartics Fig. 91, — Holding Horse's Head for Drenching. (M. H. E.) Note cloth loop under nose- band. Aloes. — Cathartic,^ laxative,- or bitter tonic, depending upon the dose given, is very reliable and satisfactory for horses, but less so for ruminants. It is very soluble in alcohol and boiling water, but imperfectly so in cold water, and usually requires 15 to 20 hours for operation. It is often desirable to combine it with one fourth its weight of ginger, and give it in conjunc- tion with nux vomica in case the bowels are torpid. Large rec- tal injections of warm water may be given until the physic acts. Doses.— Cattle, 1 to 2 oz. ; horses, 2 to 8 drams ; sheep, 1 to 2 drams; hogs, 1 to 2 drams. These doses may be administered in a ball with ginger and lard or molasses, or, as a drench, in water or sirup. Epsom salts (sulphate of magnesia). — This is a saline ea- * Cathartic, moderately vigorous physic. 'Laxative, mild physic. 282 VETERINARY STUDIES thartic, which causes a large secretion of fluids from the intes- tinal walls, thus rendering the bowel contents very fluid. It is very soluble, for it will dissolve in its own weight of warm water. This is a very satisfactory laxative or cathartic for cattle and sheep, but not so good for horses. Epsom salts is useful in small doses for horses in feverish conditions. j)oses. — Cattle take for cathartic one to three pounds; sheep and hogs take one-eighth to one fourth pound. It is frequently desirable to add one sixth the total weight of powdered ginger and give as a drench and it is better to give rather dilute drenches; e.g. the cow's dose should be dissolved in two to three pints of water, and the others in proportion. Raw linseed oil. — Raw linseed oil is used in veterinary prac- tice for diluting stronger medicines, for making liniments and various applications for external use, and it is administered internally as a laxative or cathartic, depending upon the dose used. It is very safe and but slightly irritating for horses, cattle, sheep or swine. Boses. — Cattle take two to four pints; horses, one to three pints; sheep and hogs take one fourth to one pint. Rectal injections of warm water may follow the dose of oil, and it is desirable, if there is sufficient time, to prepare horses by several warm bran mashes before giving the oil. Stimulants and Tonics Alcohol.^ — Alcohol is a difl:'usive stimulant, diuretic, antispas- modic, and diaphoretic. Large doses are narcotic. Medicinal doses check spasmodic conditions of involuntary muscle fibers, stimulate the heart and lungs, equalize circulation, and tem- porarily overcome depression. Alcohol is soluble in all pro- portions in water, and should be diluted at least four times for internal use. Doses. — Cattle, two to four ounces; horses, one to two ounces; sheep, one half ounce; hogs, one fourth to one half ounce well diluted as above. Aromatic spirits of ammonia. — This is a quick, very useful and typical stimulant. It consists of ammonia carbonate, am- ^ A diuretic stimulates the kidneys and increases the flow of urine. A diaphoretic stimulates perspiration. An antispasmodic relieves crampy conditions, especially of involuntary muscle fibres. COMMON MEDICINES 283 monia water, alcohol, water, and various aromatics. It quickly stimulates the heart, lungs, and digestive organs, and increases bronchial secretions, etc. It is antacid and leaves few harmful after effects. It is very useful in cases of exhaustion, sunstroke, colic, hoven, and in certain coughs. The dose for horses and cattle is about one ounce in half a pint of water. Sheep and swine take about one eighth as much. Camphor. — Camphor is commonly known as camphor gvun. Spirits of camphor consists of the gum dissolved in alcohol, in a strength of ten per cent. The gum is readily soluble in alco- hol, ether and chloroform, and but slightly soluble in water. Used externally in liniments, it has first a mildly stimulating and then slight local anesthetic effect. The vapor kills fleas, moths, bugs, etc. Internally it is a useful, safe, and dependable stimulant to the vital centers in cases of great depression, shock, or collapse. In urgent cases for which camphor is most commonly used it should be dissolved in olive oil and given by hypodermic injec- tion. The dose for a horse is about one dram dissolved in four drams of olive oil — about two drams of the solution to be in- jected at each place. Gentian. — Powdered gentian root is a stomachic,^ and tonic. It promotes appetite, increases the secretions and improves digestion. It has some value also as a vermifuge ; - but it is especially useful where a simple, bitter tonic is needed, as for highly fed stock "off-feed," or where debility follows an acute disease like influenza or pneumonia. It is helpful in other cases of debility which are accompanied by poor appetite and digestion. Horses take one half to one ounce and cattle one or two ounces. Ging-er. — Ginger, as usually seen, is in the powdered root — or, rather, rhizome. This is another stomachic and stimulant. It is very useful for mild digestive disturbances. It is often combined with i)urgatives as an aid and to prevent griping and depression. It is especially important with the salines, like epsom salts, given in full doses. Horses take about one ounce, and cattle two to four ounces. * Stimulates normal activities of tlie stomach. ^ E.xpels worms. LECTURE LIX COMMON MEDICINES (Continued) Antiseptics Boracic acid. — Boracic acid, a non-irritating, antiseptic pow- der or crystals. Boracic acid is mainly used externally either in solution (about 3 per cent) or as dry powder dressing for wounds. Sometimes it is used internally for colts and calves which have diarrhea. Boracic acid is soluble in 26 parts cold water, in 3 parts boiling water, or in 6 parts alcohol. For solu- tions, use the crystals. Doses. — Colts and calves take 10 to 30 grains in sirup three times a day. As an outward application for wounds and sores, the acid may be mixed with half its bulk of iodoform. Carbolic acid. — Carbolic acid deodorizes and kills germs (germicidal). In strong solutions it is irritant, caustic, and locally anesthetic. Internally it is at first a stimulating and afterwards a depressing narcotic, poisonous in sufficient dose and strength. It is used more commonly as an external dis- infectant, in 2 to 5 per cent solutions. Dilute solutions kill external parasites. Carbolic acid is useful in the treatment of ringworm used as 10 to 15 per cent solution in glycerine or linseed oil. It is not so commonly used as a dressing in surgi- cal work as formerly — usually dispensed from the drug stores as a 95 per cent solution of the crystallized drug. Corrosive sublimate (bichlorid of mercury). — This is a caus- tic, and irritant poison. It is used externally as a caustic and antiseptic. Strong solutions and ointments produce very severe blisters, and frequently destroy the hair follicles. It is chiefly used as a germicide. For this purpose it is greatly diluted. Corrosive sublimate is cheap and very satis- factory for disinfecting buildings, and other purposes where large quantities must be used. Dilute solution destroys lice and itch mites in the proportion of fifteen grains to a pint of 284 COMMON MEDICINES 285 water. For antiseptic and disinfecting purposes, it may be used four to seven grains to the pint. lodin.— lodin occurs as bluish black, heavy crystals, readily soluble in alcohol and ether, and but slightly soluble in water, although it dissolves in water readily if potassium iodid is added. Tincture of iodin is a solution of iodin and iodid of potash in alcohol and contains about 7 per cent iodin. Lugol's solution is composed of iodin, 5 ; iodid of potash, 10 ; water, 100,— giving 5 per cent iodin. Iodin is one of our most useful and dependable disinfectants and germicides for surgical work, wound treatment, etc. It is especially valuable in skin disinfection as for castration, or in treatment of the navel cords of the new born. For skin dis- infection, navel cords, etc., the tincture is used in full strength. Lugol's solution is useful and reliable for disinfectant pur- poses, diluted in water at from 2 to 4 per cent. For some pur- poses it is used still more dilute as in abortion and sterility work. When iodin is used externally by repeated treatment as a liniment for sprains, bursal enlargements, arthritis, etc., its slow, mild, but persistent, irritating and stimulating action is very useful. It is also very eifective as a fungicide as in ring- worm. Iodin is used internally for actinomycosis (see Lecture XXXII), where it is given internally in the form of iodid of potash or it may be injected as the tincture or as Lugol's solu- tion by hypodermic, directly into the diseased mass. Iodin in the form of iodid of potash is useful also, when given to pregnant dams to prevent goiter in young pigs, and lambs, and to prevent hairless pigs, etc. When used internally in excess, the warning symptoms are : catarrhal conditions at eyes and nose, scurvy skin, digestive dis- turbances, and refusal of food. Iodoform. — This is used for external and local application. It prevents infection of wounds and acts as a local antiseptic. Iodoform is useful as a dressing for wounds, especially after they have commenced to heal. It may be used alone or mixed with twice its bulk of powdered boracic acid and dusted over the wound surface. Common Hme. — Common lime is an irritant, it neutralizes acids and is astringeiit. Saturated solution, which is very dilute, is useful in diarrheas and indigestions of young animals, 286 VETERINARY STUDIES and may be given with milk quite freely. Carron oil (lime- water and linseed oil in equal parts) is an old and useful appli- cation for burns. Whitewashing is a satisfactory method of disinfecting and cleaning up outbuildings, including stables. For this purpose, fresh chlorid of lime, one half pound to the gallon may be added with advantage. Sodium chlorid (common salt). — Common salt is an essential article of food, restorative, and antiseptic. Very large doses are cathartic and more or less irritating. It is useful as a throat wash, diluted to 5 per cent solution in w^ater. As normal salt solution (about one tablespoonful to one gallon of water), it is an ideal preparation for mechanical cleaning of sensitive sur- faces and cavities, e.g., eye, vagina or uterus. For any such purpose it is a good cleanser and less irritating than plain water. Sodium hyposulphite and sodium sulphite. — These are anti- septic and deodorant ; and especially valuable for internal ad- ministration, to check fermentation and septic processes in the stomach and intestines, and are therefore valuable in conditions of diarrhea, indigestions, and hoven or bloat. Both the sulphite and the hyposulphite are readily soluble in water and are not likely to do any harm. Doses. — Horses and cattle take 8 to 10 oz. ; of the sulphite sheep and swine take 4 to 8 drams. The doses of hyposulphite are about half as large as for the sulphite. These doses are to be given as drenches, well diluted, and repeated three times daily. Smaller doses may be given every half hour in cases of bloat. LECTURE LX COMMON MEDICINES {Continued) Diuretics Saltpeter (nitrate of potash). — Saltpeter is very soluble in water, warm or cold. It is mildly antiseptic, and has slight cathartic effect. It is strongly diuretic; it increases secretion from bronchial tubes ; it is alterative, a febrifuge ^ and useful in the treatment of all classes of animals. For alteratives and febrifuge effect it is given in about half the doses that are given to stimulate the kidneys. Doses. — Cattle and horses for diuretic effect take one half to two ounces; sheep and swine, one half to two drams. These doses are given in the drinking water or as a drench. Sweet spirits of niter. — Stimulant much like alcohol or ether ; it is antispasmodic and increases the excretion from skin, lungs, and kidneys. Very large doses are narcotic. It is very useful in cases of spasmodic colic and it is a convenient heart stimu- lant. Doses. — As a stimulant and antispasmodic, horses and cattle take two to four ounces ; hogs, two to four drams. It is decom- posed by water, and should not be mixed with other medicines until just before its use. It is given as a drench with water or in sirup. As an antispasmodic it may be given to advantage with either opium or chloral hydrate. Oil of turpentine (common turpentine). — Stimulant, anti- spasmodic, antiseptic, and destroys parasites, both external and internal. It is readily absorbed when swallowed and is excreted by the lungs, skin and kidneys. Medicinal doses stimulate and overdoses irritate the mucous membrane of these organs. For medicinal purposes it is used in indigestion, and in certain con- ditions of diarrhea and tympanites (bloating) ; it is a very use- ful medicine in these conditions and one that is usually at hand. * A febrifuge reduces fever, 2S7 288 VETERINARY STUDIES It is practically insoluble in water; soluble in ether, alcohol and chloroform and dilutes well in linseed oil. Doses. — Horses take 1 to 3 ounces and cattle 2 to 6 ounces two or three times a day. The dose for sheep and swine should be about 1/6 of these quantities. Narcotics and Sedatives Chloroform. — Stimulant, antispasmodic, anodyne,^ anesthetic. Its stimulating effect resembles that of alcohol, but is less pro- nounced and more temporary. Applied externally, it evapo- rates rapidly and is cooling; but is very irritating when applied externally and prevented from evaporating. Chloroform is very useful in colic, cough, and other spasmodic conditions given internally with eight to ten times its bulk of raw linseed oil or milk and well shaken. It is very slightly soluble in water, but dissolves freely in alcohol, ether or turpentine, and is useful in spasmodic colic. Doses. — Horses and cattle take two to four drams repeated every two to three hours, if necessary till the patient staggers. Sheep and hogs take one half to one dram repeated frequently as for horses and cattle. Sodium bromid. — Small white crystals, readily soluble in water. This medicine is usually considered as the least toxic, least irritating to the stomach and the most hypnotic ^ of the bromids. It acts as a nerve depressant especially on the motor centers. The bromids are often combined with chloral hydrate and are used to control nervous conditions with excessive motor activity, as in convulsive conditions. Doses. — Horses and cattle take one half to two ounces. Opium. — Medicinal doses relieve pain and spasmodic condi- tions, reduce congestion and inflammation ; check intestinal se- cretions and peristaltic movements ; and with some animals pro- duce sleep. The various preparations of opium are used espe- cially for the purpose of relieving pain. Opium is a typical anodyne (pain reliever), but there are very painful conditions that arise in practice under which it should never be given, which it is not thought practical to explain in this short lecture ' An anodyne relieves pain. An anesthetic removes sensation. ^A hypnotic produces sleep. COMMON MEDICINES 289 further than tliat the person who is giving opium preparation of any kind to any domestic animal must not forget that it checks intestinal secretion and peristaltic movements of the intestines, and in this way may cause decided constipation at just a time when this would be serious. DOSE HORSES CATTLE SHEEP HOGS Morphine sulphate . . . 3-5 gxs. 3-8 grs. 1/2-2 grs. 1/2-2 grs. Tincture opium (hiu- danum) 1-2 ozs. 1-3 ozs, 2-6 drs. 2-6 drs. The tincture should be diluted with water or sirup the same as for alcohol. Morphin is an active principle of opium, and has the essen- tial physiological properties of opium. Cattle and sheep take very large doses. Morphin and various preparations of opium are sometimes employed in spasmodic colic and may be com- bined with stimulants or anodynes like ether, sweet spirits of niter or chloral hydrate. It is usually advisable to give a laxa- tive soon after the opium. All opium preparations must be used with great caution, even in relieving pain. They may mask important sj-mptoms and by arresting secretion and excretion, they may do more harm than good. Astringents Alum (potassium sulphate). — An astringent and styptic.^ This is not much used internally in veterinary practice. Within recent years very large doses have been used internally and with good results in laminitis. (See Lecture XLVI.) Alum is soluble in cold water, 1 :*9, and very soluble in hot water. It is antiseptic, astringent and mildly caustic, locally it coagulates albumin and checks secretion. In the circulation, alum constricts the capillaries. It is more commonly used externally for its astringent and mild caustic action on profuse granulations, and "weeping" surfaces, and for its antiseptic and astringent effect in stopping leakage of synovia from an open joint with small puncture. Alum is a common ingredient of astringent and antiseptic dusting powders. Dose. — The usual dose for internal use for horses and cattle is 1 to 4 drams, well diluted. ' A styptic checks hemorrhage, aids coagulation. 290 VETERINARY STUDIES Burnt alum is common alum from which the water has been driven off by heating. It is quite astringent, somewhat caustic, and is sometimes used on excessive granulations in an open wound. Tannic acid (tannin). — This is a very light, yellowish pow- der obtained from oak galls. It is soluble in water and glyc- erin, a powerful astringent and styptic. It coagulates albumin, checks secretion locally where applied, and is but slightly irritating. Tannic acid is often used on mucous membranes for its astrin- gent effect in checking the local secretion, as in certain diar- rheas when a non-caustic astringent is needed. Externally, tan- nic acid is used on superficial collar and other harness sores, dusted on as a powder, or dissolved in water or glycerin, about 2 ounces to the pint. Tannic acid dissolved in glycerin is very useful for sore and chapped teats. Dose.— The internal dose is 1 to 3 drams in solution for horses and cattle. Its chief use for the stockman will be for external application. Miscellaneous Collodion. — Collodion is a solution of gun cotton in ether and alcohol. Flexible collodion contains castor oil and Canada bal- sam, also, and is better for most veterinary uses than plain collodion. It must be kept in a tight bottle and not exposed to an open flame. It is used only as an external application and is very useful in minor surgery. When painted over a dry surface, it dries promptly and leaves a thin adherent and protective covering that is not sticky. This gives excellent protection against infection and minor injury to superficial wounds. It is useful to cover small, clean wounds, cracked and chapped teats, etc. Other medicines are often added in order to use the collodion as a carrier. MINOR SURGICAL OPERATIONS LECTURE LXI MINOR SURGICAL OPERATIONS Castration This is a very common and useful operation which the stock- man should understand. Colts should ordinarily be castrated by qualified veterinarians. Age. — Calves may be castrated at almost any age, but better at between two and four months. Colts may be operated on at i-'iG. !»:.'. -To Throw Cattle. (J/. ]{. E.) Pull straight back on the rope. any age after a few months old, but better at about one year — usually under two years; Iwmhs at one to three weeks and pigs any age, but better about two weeks before or two or three weeks after weaning. Restraint. — Calves small enough to be handled easily are 291 292 VETERINARY STUDIES usually held on the ground, clean grass preferred, with the top hind leg held forward ; older calves and bulls may be easily Fig. 93, — Eestraint for Castration. (White.) operated standing if well confined. Look out for kicks, espe- cially from older bulls. For the standing operation, it is safer to confine the hind legs by a figure 8 rope tie above the hocks or by ordi- nary hock kicking hobbles, or to throw and tie securely in some eases. Yonng pigs are held by an assist- ant in either of several convenient ways. Heavier shoats are usually castrated on the ground, clean grass, held with the top hind leg forward by an assistant. Or they may be ''hog tied" for the two front and upper hind leg. A heavy boar may be tied short by a loop around the upper jaw and castrated standing. In this case it is advisable to have two assistants hold a pole under the belly, well back, to keep the boar from lying down. The standing operation on boars is inconvenient for some operators. See Figure 93. Fig. 94. — General View of Scrotum and Sheath. (White.) A, A, Long incisions par- allel to the median line BC. MINOR SURGICAL OPERATIONS 293 Young lamhs are held by an assistant and may be docked at the same time. Large rams may be "hog tied" like the boar on the ground, except that the lower hind leg should be included in the tie. The upper may be either held forward or included in the tie. Older lambs and small rams may be held on the rump, belly up somewhat as for shearing, the assistant holding both hind legs. Season.— Good weather is desirable especially for lambs— Fig. 95. — A Good Type of Emasculator. (White.) usually spring or fall. Dust should be avoided; therefore a quiet day is preferred. Operation. — The scrotum incisions should be parallel to and reasonably near the median line or "seam." See Figure 94. This should be done with a free sweeping cut and few move- ments. Except in case of a ruptured animal, young boar, for instance, the incision should go through the thin transparent sac ^ around the testicle. The incision should be reasonably long and extend to the lowest point where pus could otherwise collect. The testicle is removed in various ways, the choice depending principally on the danger of hemorrhage. For lambs under about three weeks, the cord is simply pulled in two after free- ing the testicle. For pigs, calves and older lambs, the blood vessels may be divided by moderate pulling and slow scraping '■ Peritoneum. 294 VETERINAEY STUDIES with the castrating knife, the rest of the cord having been cut first. For still older animals, an emasculator of the type shown in Figure 95 is desirable both for convenience and safety. It is well to hold the cord in the emasculator for a little while after closing the jaws. Dangers. — On account of the peculiar anatomy of the parts involved in castration, there are several possibilities of trouble. The student should understand that the peritoneal or belly cavity is continuous with the inguinal canal and sac around the testicle. As the testicle of the young animal descends from the belly to the scrotal cavity, it carries with it the peritoneum, which forms a thin membranous sac closely around the testicle. Thus an infection of the interior of the scrotum or stump of the cord, after removing the testicle, easily leads by extension directly to the abdominal peritoneum and to a fatal peritonitis. Dangerous hemorrhage sometimes occurs after this operation, hence the necessity of keeping recently castrated animals under observation for a few hours. For control of hemorrhage, see Lecture on Wounds. Such hemorrhage is usually due to too rapid scraping or to accidental nicking of the artery above the point of division or to a poor emasculator. Some animals are natural bleeders, i.e., their blood does not clot and they bleed dangerously from wounds that would be trivial for another. An incomplete or inguinal hernia may be overlooked and the intestines come out after castration. Examine for such hernia before removing the testicle. Premature closure of the incision may occur especially if the incision is too small. Such closure prevents proper drainage and favors dangerous disorders, leading to much swelling and even to peritonitis. Make a reasonably long incision at the proper place. If necessary, reopen the wound with clean fingers. Allow plenty of mild exercise beginning as soon as danger from hemorrhage is past. Dehorning There are several ways of performing this useful operation, all intended to either prevent the horn growth as in case of young calves, or else to so remove the horn as to avoid the growth of an unsightly stub. MINOR SURGICAL OPERATIONS 29o Age. — Young calves to be treated by the caustic method, must be treated at about 3 to 5 days, preferably not over 7 days old. After this a