1975 UC-NRLF B 3 flTfl flMD THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA PRESENTED BY PROF. CHARLES A. KOFOID AND MRS. PRUDENCE W. KOFOID I BULLETIN No. 19. U.S. DEPARTMENT OF AGRICULTURE. BUREAU OF ANIMAL INDUSTRY. THE INSPECTION OF MEATS FOR ANIMAL PARASITES. I. THE FLUKES AND TAPEWORMS <>!' CATTLE, SHEEP, AND SWINE, WITH SPECIAL REFERENCE TO THE INSPECTION OF MEATS. By Cir. WARDELL STILK.S. [I. COMPENDIUM OF THE PARASITES, ARRANGED ACCORDING TO THKIli HOSTS. By ALBKRT HASSAU.. [II. BIBLIOGRAPHY OF THE MORE IMPORTANT WORKS CITED. By ALBERT HASSAI.I.. Prepared under the direction of Dr. 1>. E. SALMON, CHIEF OF THE BUREAU OF ANIMAL INDUSTRY. February ><, l^fH. WASHINGTON : GOVERNMENT PRINTIN( J OFFICE. 1898. BULLETIN No. 19. U. S. DEPARTMENT OF AGRICULTURE. BUREAU OF ANIMAL INDUSTRY. THE INSPECTION OF MEATS FOR ANIMAL PARASITES. I. THE FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE, WITH SPECIAL REFERENCE TO THE INSPECTION OF MEATS. By CH. WARDELL (STILES. II. COMPENDIUM OF THE PARASITES, ARRANGED ACCORDING TO THEIR HOSTS. By ALBERT HASSALL. III. BIBLIOGRAPHY OF THE MORE IMPORTANT WORKS CITED. By ALBERT HASSALL. Prepared under the direction of Dr. D. E. SALMON, CHIEF OF THE BUREAU OF ANIMAL INDUSTRY. Issued February 8, 1898. WASHINGTON : GOVERNMENT PRINTING OFFICE. 1898. LETTER OF TRANSMITTAL U. S. DEPARTMENT OF AGRICULTURE, BUREAU OF ANIMAL, INDUSTRY, Washington, D. C., October 4, 1897. SIR: I have the honor to transmit herewith, and to recommend for publication as Bulletin No. 19 of this Bureau, under the general title "The inspection of meats for animal parasites," a report on "The flukes and tapeworms of cattle, sheep, and swine, with special reference to the inspection of meats," prepared under my direction by Dr. Ch. Wardell Stiles, Zoologist of the Bureau. Appended to the report, and as valuable adjuncts thereto, are a "Compendium of the parasites" and a " Bibliography," prepared by Albert Hassall, M. E. C. V. S., of the Zoological Laboratory. Although the report is intended primarily for the use of the meat inspectors of this Bureau, it will be found of general interest to all sanitarians, since it treats of the communica- bility of certain parasites from animals to man, and suggests the neces- sary methods of prevention and treatment therefor. The publication and distribution of the bulletin will serve a useful purpose in dissemi- nating knowledge of the precautions that are required to eradicate certain of the most important parasites affecting domesticated animals in this country parasites which are a menace to the public health. Its early publication is desirable, as there is no work in the English language covering the subjects of which it treats. Respectfully, D. E. SALMON, Chief of Bureau. 3 M353G86 LETTER OF SUBMITTAL. U. S. DEPARTMENT OF AGRICULTURE, BUREAU OF ANIMAL, INDUSTRY, ZOOLOGICAL LABORATORY, Washington, D. simple intestinal caeca, ivhich extend slightly beyond the middle of the body ; in front of acetabulum are four large unicellular glands with rather long ducts, extending to oral sucker ; three primordial genital glands in distal half of body ; terminal excre- tory canal median, branching immediately distal of testicles. The Muscle Fluke of Swine (Agamodistomum suis), p. 28. (5) Parasitic in liver, lungs, rarely abdominal cavity of cattle, sheep, or swine. Body large, shaped like a flat fish, dark colored; intestinal caeca, testicles and ovary profusely branched; freshly laid egg does not contain embryo. Fascicles (Fasciola), 6. Parasitic in liver or pancreas of cattle, sheep, or swine. Body smaller; intestinal caeca very simple, long, tubular, extending beyond acetabulum to posterior portion of body; oesophagus comparatively short; genital pore at bifurcation of intestine; tes- ticles two, may be slightly lobate, near acetabulum; ovary posterior of and smaller than testicle, but anterior of transverse rifello-dnct; ovary and testicles anterior of mass of uterine coils which extend to posterior end of the body. Dicrocoeles (Dicrocoelium), 1. Fascicles (Fasciola). (6) Parasitic in liver or lungs of cattle. Body (figs. 28-30) flesh-colored, very large aud thick, 20 to 100 mm. long by 11 to 26 mm. broad; anterior conical portion not very distinct from posterior portion ; posterior extremity bluntly rounded ; vitellogene glands situated ventrally of intestine; oesophagus generally one and one-half times as long as pharynx; eggs 109 to 168 // by 75 to 96 //. The Large American Fluke (F. magna), p. 49. Parasitic in liver or lungs of cattle, sheep, hogs, etc. Body (figs. 2 and 3) 18 to 51 mm. long (occasionally longer) by 4 to 13 mm. broad; anterior conical por- tion generally very distinctly bounded from posterior portion; posterior ex- tremity bluntly pointed; vitellogene glands both dorsal and ventral of intes- tine; oesophagus rarely one and one-half times as long as the pharynx; egg 105 to 145 /.i by 63 to 90 // The Common Liver Fluke (/'. hepalica), p. 29. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 23 Parasitic in liver of Senegal cattle. Body (figs. 28 and 24) 26 to 38 mm. long by 6 to 8 mm. broad, flat, Hnguiform, sides of posterior portion nearly parallel for some distance but tapering toward posterior extremity; ventral sucker large and promi- nent; egg 143 to 151 /.i by 82 to 88 n. The Narrow Liver Fluke (F. hepatica angusta), p. 48. Parasitic in the Indian buffalo (Bos bubalis) and cattle (Bos taurus). Body (figs. 25 and 26) 25 to 31 mm. long by 6 to 8 mm. broad; sides of body nearly parallel for some distance; posterior extremity somewhat rounded. The Egyptian Liver Fluke (F. hepatica aegyptiaca), p. 48. Parasitic in the liver of giraffes and cattle (f). Body (fig. 27) 75 mm. long by 5 to 12 mm. broad, flat, oblong, lanceolate; anterior extremity cylindrical, attenuate; pos- terior extremity obtuse; sides nearly parallel for greater part of length; oral sucker 1.12 mm. in diameter, ventral sucker somewhat larger; oesophagus extends nearly to acetabttlum; S to 10 lateral brandies to each intestinal caecum; other organs agree with F. hepatica The Giant Fluke ( F. gigantica), p. 49. Dicrocoeles (Dicrocot'lium). (7) Parasitic in liver of cattle, sheep, and swine. Body (figs. 36 and 37) lancet form, 4 to 10 mm. long by 1 to 2. 5 mm. broad; anterior end much more attenuate than posterior end; semitr an spar ent, spotted brown by eggs; cuticle without spines; oral sucker 0.5mm. in diameter , subterminal ; ventral sucker 0.6 mm. in diameter, one-fifth the length of body back of mouth ; mouth followed by an oesophagus which, about halfway between oral sucker and acetabulum, immediately in front of cirrus pouch, branches into tico simple intestinal caeca; the latter extend one each side to about the posterior quarter of the body ; cirrus pouch present; cirrus long, filiform, straight; testicles lobed, one posterior to the other, and situated immediately posterior of acetabulum; uterus sinuous, very long, extending backward beyond the end of the intestine to pos- terior portion of body, then running forward in loops to genital pore, and rendered prominent by presence of brown eggs; vitellogene glands in marginal portion of middle third of body ; eggs (fig. 38) 40 to 45 jj, by 30 /.i, containing embryo at time of ovipont The Lancet Fluke (D. lanceatum), p. 55. Parasitic in pancreas of " cattle," Indian buffalo, and sheep, in Asia. Body (fig. 40) somewhat similar to the common fluke but proportionally broader and more pointed at distal extremity ; S to 15 mm. long by 5 mm. broad; blood red in color ; cuticle without spines; oral sucker subterminal; ventral sucker slighfly larger than oral sucker, one-third the length of the body back of the mouth; pharynx, oesophagus, and intestines about the same as in D. lanceatum; cirrus-pouch pyriform ; testicles irregularly lobed, in lateral portion of median field, on same transverse plane, near acetabulum; uterus of similar type to that of D. lanceatum; vitellogene glands only about one-fifth as long as body, situated in marginal portion of middle third; eggs ovoid, thick shelled, 44 JLI to 49 /.i by 23 /.i to 30 JLI. The Pancreatic Fluke (Z>. pancreaticum), p. 57. Blood Flukes (Family Schistosominae ; Genus Schistosoma). [Acetabulum peuduculate; intestinal caeca unite or anastomose distal of acetabn- luui ; male shorter, thicker, and broader than female, the margins curling ventrally to form canal for filiform female ; testicular complex consists of a double series of four or more sacular bodies.] (8) Parasitic (fig. 41) in blood of man and cattle (?). Male 4 to 14 mm. long by 1 mm. broad; female attains 13 to 20 mm. long by 0.28 mm. broad by 0.21 mm. thick ; eggs ovoid to fusiform 120 to 197 /u long by 40 to 73 // broad. The Human Blood Fluke (S. haematobium), p. 58. Parasitic (fig. 45) in blood of cattle. Body thicker than the Human Blood Flukes; the dorsal surface of the inner fold of the male is provided with a longitudinal groove (fig. 46) into which the end of the outer fold extends; eggs fusiform, 160 to ISO /* by 40 to 50 ft The Bovine Blood Fluke (S. bods), p. 60. 24 INSPECTION OF MEATS FOB ANIMAL PARASITES. Amphistomes (Amphistornidae). (9) Parasitic in intestinal tract or gall ducts of sheep, cattle, zebu, and gayal. Pharynx without lateral sacs 10. Parasitic in intestinal tract of zebu and gayal. Pharynx with two lateral sac*; the greater part of the ventral surface of posterior portion of body is covered with numerous papillae Homalogaster, 13. (10) Parasitic in intestinal tract or gall ducts of sheep, cattle, and zebu. Ventral pouch very small or absent True Amphistomes (Amphistoma), 11. Parasitic in intestinal tract of cattle, zebu, gayal, and Indian buffalo. Ventral pouch large, extending to posterior portion of body. Pouched Amphistomes (GastrothylasJ, 12. True Amphistomes (Amphistoma). (11) Parasitic in rumen of sheep and cattle. Body (figs. 49 and 50) 4 to 13 mm. long by 1 to 3 mm. broad; conical, pinkish white. .The Conical Fluke (A. cervi), p. 64. Parasitic in gall bladder and hepatic ducts of zebu. Body lanceolate, 8 to 10 mm. long by 3 to 4 mm. broad, rather similar to the Conical Fluke, but somewhat flat- tened dorso-ventrally A. explanatum, p. 67. Parasitic in stomacji of zebu. Body (fig. 56) somewhat similar to A. cervi, but more oval, and somewhat flattened dorso-rentrally ; about 11 mm. long by 6.6 mm. broad. A. bothriophorum, p. 67. Pouched Amphistomes (Gastrothylax). (12) Parasitic in stomach of zebu and cattle. Body (figs. 57-62) reddish brown to grayish green, 9 to 15 mm. long by 4 to 5 mm. broad G. crumenifer, p. 67. Parasitic in stomach of gayal. Body (fig. 63) pyriform, 10 mm. long by 5 mm. broad at posterior extremity G. Cobboldii, p. 67. Parasitic in stomach of gayal and zebu. Body attains (fig. 64) 20mm. long by 4 mm. broad ; intestine only half as long as body G. elongatum, p. 67. Parasitic in stomach of Indian buffalo. .Body (figs. 65 and 66) deep red, cylindrical to conical, attains 7 to 10 mm. long by 2 to 2.5 mm. broad G. gregarius, p. 67. Homalogaster. (13) Parasitic in caecum of gayal. Body (fig. 67) lanceolate; testicles small. H. paloniae, p. 67. Parasitic in caecum of "cattle" (= (?) zebu). Body mm. long; oral sucker with digitate papillae; testicles lateral and divided into two equal lobes with irregular contours, so that there appear to be four testicular masses H. Poirieri, p. 67. TAPKWOKMS. (Cestoda.) (14) Larval tapeworms or bladder worms (figs. 68, 76, 84, 97, and 105) parasitic in muscles, liver, lungs, etc., but not in lumen of intestinal tract; the head, which is generally provided with hooks, lies inside the cyst; body unseg- mented, generally surrounded by a cyst of connective tissue ; no genital organs developed ; these forms become adult in man and carnivorous animals, and are of great importance from the standpoint of meat inspection. .. Taeniinae, 15. Adult tapeworms (fig. lit), found in the intestine of cattle, sheep, and swine ( ?), or in gall ducts of sheep Anoplocephalinae, 18. Bladder Worms, or Larval Tapeworms (Hard-shelled Tapeworms, Subfamily Taeniinae; Genus Taeuia). (15) Parasitic in muscles, abdomin >1 cavity, lungs, and liver. One head in each cyst Bladder Worms ( Cysticercus), 16. Parasitic in any organ of body except intestine, most frequent in liver, lungs, and brain. Numerous heads may be present 17. FLUKES AND TAPEWORMS OF CATTLE, SHEEP. AND SWINE. 25 Bladder Worms (Cysticercus). (16) Parasitic in cattle; found in the muscles, especially those of mastication, more rarely in lungs or liver. Body (fig. 68) spherical to elliptical, 2.5 to 10mm. long - by 3 mm. broad; whitish to gray, with a small yellowish spot due to the invaginated head; 110 hooks present; the bladder contains but little liquid. Transmissible to man Beef Measle Bladder Worm ( 1 C. bovis), p. 71. Parasitic in swine; found in the muscles. Body (figs. 75 and 76) ellipsoid, 6 to 10 mm. long by 5 to 10 mm. broad, with a white spot corresponding to the invaginated head ; head armed with a double row of 24 to 32 hooks of two differ- ent sizes (see description of adult, p. 84) ; the bladder contains but little liquid. Transmissible to man Pork Measle Bladder Worm ( l C. cellulosae), p. 89. Parasitic in cattle, sheep, and swine; young, stages in the liver, older stages found hanging into the body cavities, attached to omentum, etc. Bladder (figs. 84, 91, and 92) large, varying from size of a pea to that of a man's fist, occasionally attaining 160 mm. by 60 to 70 mm. ; neck long ; invaginated head armed with a double row of 28 to 44 (generally 36 to 38) hooks, of two sizes (see description of adult, p. 101) ; the bladder contains considerable liquid. Transmissible to dogs, but not to man. The Thin Necked Bladder Worm ( 2 C. tenuicollis), p. 96. Cocnurus and Echinococcus. (17) Parasitic in nervous system, especially the brain, of sheep and calres. Bladder (figs. 94 and 97) varies from size of a pea to that of a hen's egg, and is composed of a hydatid cyst (cuticle thin) which forms numerous small imaginations (as many as 500 in large specimens), in each of which a head develops without the forma- tion of brood capsules ; head armed with a double row of 22 to 32 hooks, of two sizes (see description of. adult, p. 101). Transmissible to dogs, but not to man. The Gid Bladder Worm ( 2 Coenurus cerebralis), p. 108. Parasitic in any organ, particularly the liver and lungs of man, cattle, sheep, swine, etc. Bladder (figs. 101 and 105) varies from size of a pea to that of a child's head, assuming different forms, as described on p. 102; the hydatid cyst has a thick laminated cuticle; the heads are armed with a double row of 28 to 50 hooks, of two sizes (see characters of adult, p. 101), and develop in brood capsules, which are attached to the cyst wall. The adults develop in dogs, but not in man. This is the most important parasite of meat inspec- tion The Echinococcus Hydatid ( 2 Echinococcus polymorphic), p. 113. Adult tapeivorms of Cattle, Sheep, and Swine ( ?) (Subfamily 3 Anoplocephalinae). (18) Posterior border of segments not fringed; parasitic in the intestine 19. Posterior border of segments fringed (figs. 122 and 124). Parasitic in intestine and bile ducts of sheep. Genital pores double; strobila 15 to 30 cm. long; head large, 1.5 mm. broad, nearly square on apex view ; neck flat, broad, and short; broadest segments measure 5 to 8 mm. wide by 0.4 to 0.6 mm. long, and are situated about 2 cm. from posterior end, the end segment showing a decided tendency to become longer and narrower; gravid segments attain 2.2 mm. in thickness; uterus single, transverse, but undulate with cornucopia-like egg pouches ; testicles form a band in distal portion of median field ; horns of pyri- forin body around embryo not developed. The Fringed Tapeworm (Thysanosoma actinioidex), p. 128. 1 For characters of the adult form in man, see key, p. 84. 2 For characters of the adult form in dogs, see key, p. 101. 3 This key to the adult forms is extremely artificial, as characters have been selected which will most easily enable a determination of the Avorms. For a key expressing more closely the true relations of the forms to each other, see Stiles & Hassall, 1893, p. 88, and Stiles, 1896, p. 214. 26 INSPECTION OF MEATS FOR ANIMAL PARA8ITES. (19) Genital pores double, segments generally quite broad; pyriform body well developed. Parasitic in cattle and sbeep Moniezia, 20. Genital pores usually single, rarely double, and then only in strobilae, which contain single-pored segments in the majority. Parasitic in sheep, cattle (?), and swine (:'). Strobila 1 to 2 meters long; head 0,5 to 1 mm. broad; neck absent or present; most of the segments broader than lony, only the posterior segments longer than broad; unripe segments of ten present a zigzag appearance; largest segments ~> to 6.5 mm. broad by 1 to 3 mm. long; testicles divided into two groups and confined for tin- most part to the lateral fields; uterus same as in the Fringed Tapeworm. Giard's Thysanosoraa (Th. Giardi), p. 129. Genital pores single; segments very narrow. Parasitic in sheep and cattle (.*). Stiievia, 24. Moniezia. (20) Interproglottidal glands absent Alba group, 21. Intcrproglottidal glands linear (fig. 113) Plauissima group, 22. Interproglottidal glands circular, groups around blind sacs (tig 118). Expansa group, 23. Neck absent; head large, decidedly lobed; strobila 40 cm. long; segments attains mm. in breadth. Doubtful species, parasitic in sheep Moniezia nullicoUi*. (21) Parasitic in sheep. Strobila nearly half a meter long by 2.5 mm. broad; gravid seg- ments may attain 2.5 mm. broad by 5 mm. long; genital pores in middle or anterior half of lateral margin; cirrus pouch about 0.18 mm. long; eggs GO ju, pyriform body 20 /.(, horns end in a knob - Vogt's Moniezia (M. Vogti), p. 127. Parasitic in sheep and cattle. Strobila 0.60 to 2.5 meters long; head subquadrangu- lar, 1.15 to 1.4mm. broad; neck 1.5 to 5.3 mm. long; gravid segments attain 8 to 14 mm. broad by 2 to 6.5 mm. long by 1.5 mm. thick; testicles arranged in a quadrani/le: eggs 60 to 88 //, bulb of pyriform body 16 to 24 ju, horns 8 to 20 u. The White Moniezia ( M. alba), p. 127. (22) Parasitic in cattle and sbeep. Strobila (fig. Ill) 1 to 2 meters long; yellowish; head 0.4 to 0.9 mm. broad; neck thin, short or long; segments always broader than long; gravid segments attain 12 to 26 mm. broad by 1 to 1.75 mm. long, generally thin and flat ; Interproglottidal glands large and very distinct ; tes- ticles arranged at first in two triangles, in older segments in a quadrangle; 400 to 600 testicles present in a segment ; eggs 63 /i, bulb of pyriform body 20 //, horns 24 jn The Flat Moniezia ( M. planissima), p. 127. Parasitic in sheep and cattle. Strobila attains 4 meters in length; head about 1 mm.; neck 2 to 2.5 mm. long; suckers very distinctly lobed and sharply separated from neck; segments always broader than long; gravid segments may attain 12 mm. broad by 3 mm. long by 2 mm. thick; interproglottidal glands extremely indistinct; eggs 80 to 85 /<, pyriform body 18 /J... Van Benedeu's Mouiezia (M. Benedeni), p. 128. Parasitic in sheep. Strobila 1.5 to 2 feet long; head square, 0.9 mm.; gravid seg- ments attain 8 mm. broad by 1. 5 mm. long ; but the end segments may measure r > mm. broad by 2 mm. long; testicles arranged in a quadrangle; interproglottidal glands small; eggs 55 to 65 ju Neumann's Moniezia (M. Neumanni), p. 128. (23) Parasitic in cattle and sheep. Strobila (fig. 116) attains 4 to 5 meters in length : anterior portion usually whitish, posterior portion usually yellowish; head 0.36 to 0.7 mm. broad; segments always much broader than long, gravid seg- ments attaining 16 mm. in width and are quite thick; end segments never as long as broad; testicles usually arranged in a quadrangle, rarely in two tri- angles except in younger segments; eggs 50 to 60 //, bulb of pyriform body 20 /J. The Broad Moniezia (M. expansa), p. 128. Parasitic in sheep. Strobila (fig. 120) attains 1.6 to 2 meters in length; cream to whitish in color; head 0.6 to 0.7 mm. broad; neck filiform, 2mm. long; seg- ments generally broader than long, rarely over 6 mm. broad by 2 mm. long; although end segments are occasionally found which are square or even slightly FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 27 longer than broad; testicles usually arranged in two triangles; eggs 52 to 60 u, bulb of pyrifonn body 20 to 24 //, horns 12 to 15 /it. The Triangle Mouiezia ( M. triyonophora), p. 128. Stilesia. (24) Strobila transparent, whitish or grayish yelloiv, 45 to 60 mm. Jong, not over 2.5 mm. broad ; head 0.5 to 1 mm. broad; median portion of median field transparent; two lateral cornucopia-like egg pouches present in each segment. The Globipunctate Tapeworm (S. globipunctata), p. 130. Strobila attains nearly 3 meters in length, but not ocgr 3 mm. in breadth; head 1.5 to 2 mm. broad; median field occupied lit/ transverse uterus. The Centripunctate Tapeworm (S. centripunctata),p. 130. FLUKES, OR TREMATODES (Order Trematoda). The following technical description shows the systematic position and general structure of the flukes under discussion: [Suborder Malacocotylea : Digenea. Families Fasciolidae and Amphistomidae. See figs. 3, 29, 30, 37, 41, 42, 43, and 50.] With the exception of the Blood Flukes (Schistosoma), they are all hermaphrodites. They are flat or conical worms, always longer than broad; on the anterior extremity is situated the mouth, surrounded by a muscular organ, known as the oral sucker and curved slightly ventrad. There is a second sucker (the acetabulum}, which is situated in the median ventral line; in the Fasciolidae the acetabulum is generally found on the anterior half of the body, while in the family Amphistomidae it is at or near the posterior extremity. The surface of the worms is generally more or less covered with minute spines, or tubercles. The digestive tract consists of the mouth, a short oesophagus, and two blind saca (intestinal caeca), which represent the true intestine. The anterior portion of the oesophagus is generally connected with the mouth by a muscular bulb (the pharynx) ; the posterior extremity bifurcates, one branch being connected with each intestinal caecum. The intestinal sacs are usually simple elongated tubes, but in the genus Fasciola they branch freely (fig. 29). In Schistosoma the two caeca unite after pass- ing the acetabulum. An amis is never present. Genital organs. The genital pore is in the ventral median line in all species here de- scribed, the male copulatory organ (cirrus or penis) lying very close to the female open- ing (vulva). Male organs : A cirrus is frequently seen extruded from the genital pore, and in those cases it appears as a curved organ, varying in size according to the spe- cies; usually the cirrus is invaginated in the cirrus pouch. Through its center runs a canal (the ductus ejaculatorlus) which receives the spermatozoa from a vesicula semi- nails. The latter is partially or entirely included in the pouch ; at its posterior end it receives the two vasa deferentia, through which the spermatozoa are con- ducted from the testicles. The testicles, generally two in number, one right and one leir, are more or less round, lobed, or branched. Female organs: The vulva leads into a canal, the anterior portion of which is known as the meiraterm; this is con- tinued as the uterus, which forms more or less numerous folds in the median portion of the body and finally leads to the so-called shell-gland which may frequently be seen in fresh specimens (F. magna and others) as a round body a short distance pos- terior of the acetabulum. In the center of the shell gland is a canal (the ootyp), in which four canals (uterus, oviduct, Laurer's canal, and vitello-duct) come together. The ovary in some species is globular, in others branched, and connects with the ootyp through the oviduct. The Laurer's canal runs from the ootyp dorsad in curves and opens to the exterior on the dorsal surface; its function is still doubtful, but 28 INSPECTION OF MEATS FOR ANIMAL PARASITES. homoiOgically it represents the uterus of restores. The ritellogene (/lands are two in number and are situated laterally of the longitudinal intestinal tubes; they vary in size in different species, are generally quite elongated, and are composed of numerous branches much like a bunch of grapes in form, all of which connect with a longi- tudinal vitello-duct (one on each side of the body); these longitudinal ducts are in turn connected by a pair of transverse ducts which unite in the median line, imme- diately posterior of the shell-gland, to form a common reservoir; this in turn empties into the ootyp through the short vitello-duct mentioned above. The vitellogene glands produce yolk cells which are associated with the true ovum 10 form the eggs. Excretory system. At or near the posterior extremity, generally somewhat dorsally, is situated a small pore (porusexcretorius), which leads into a median terminal reside; this latter gives oft' longitudinal branches; these in turn give off secondary branches which ramify throughout the body, each small branch ending in an excretory organ. Nervous system. A set of ganglia is found at each side of the pharynx ; these gan- glia are connected by a dorsal commissure and give off numerous nerves to various parts of the body. The largest nerves are the two ventral longitudinal nerves which run antero-posteriorly, and can frequently be seen in fresh specimens. Development. See p. 30. Cattle (Bos taurus) are alleged to be infested with fifteen kinds of flukes, only two of which, the Large American Fluke and the Common Liver Fluke, are positively known to occur in the United States. Osier- has found the Conical Fluke at Montreal, where it was not uncommon ; he also found the same parasite in cattle in ^ova Scotia. Sheep (Ovis aries) are infested with five known species of flukes, only one of which, the Common Liver Fluke, is known to be in the United States; the Conical Fluke, as stated above, is found in Canada. Hogs (Sus scrofa domestica] harbor three known species of flukes, only one of which, the Common Liver Fluke, is found in the United States. Willach (1893) has described a Monostomum hepaticum suis from the liver of hogs; this supposed fluke is evidently a partially developed bladder worm (Cysticercus tenuicollis) (see p. 96). DISTOMES (Flukes of the Family Fasciolidae). Hermaphroditic Distomes (Flukes o,f the Subfamily Fasciolinae). AG-AMIC, OR IMMATURE, DISTOMES (Genus Agamodistomum). This is a purely artificial group, of biologic rather than systematic nature. One immature fluke is occasionally found encysted in the muscles of hogs. 1. The Muscle Fluke of Swine (Agamodistomum suis). [Fig. 1.] SYNONYMY. Distomum musculorum suis Duncker, 1896. BIBLIOGRAPHY. Duncker (1896). This small (0.5 mm. to 0.7 mm. long by 0.2 mm. broad) parasite was discovered in 1881 by G. Leuuis (a trichina inspector in Saxony), and has since been found by several other trichina inspectors of Germany. As it appears never to have been biuomially named, 1 propose to call it FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 29 Agamodistomum stiis. The worm lies free or encysted in the connective tissue between the muscle fibers; it is exceedingly rare and is of no known practical importance in meat inspection, except that in a super- ficial and careless microscopic examination it might be mistaken for sarcosporidia, or possibly for trichinae. Nothing is known of its life history, but it is supposed to be a purely accidental para- site in swine. We are not aware of its ever having been recorded in this country. FASCIOLES (Distomes of the Genus Fasciola). The genus Fasciola contains the large, flounder-like, parasites found especially in the liver of herbivorous animals and known under the general term " liver flukes." Of these Fascicles, or "liver flukes," we find two forms in American cattle (F. may-no, and F. hepa- tica), one form (F. hepatica) in American sheep, while a third form (F. Jacksoni 1 ) has been found in Xorth America, South America, and in India in the liver of elephants, and a fourth form (F. giyantica 1 ) is described by Cobbold from the liver of the giraffe. It is quite generally admitted that these Fascioles, owing to their larger size, are more harmful than other flukes. Until a short time ago it was supposed that we had but oue form of fluke in American cattle, but Hassall (1891) and Francis (1891) showed, almost simultaneously, that two distinct forms are found, one form (F. hepatica) being present in the liver, very rarely in the lungs, the other (F. magna), a much larger worm, infestin liver and lungs. PIG. 1. The Muscle Fluke (Agamo- digtomumsuis), occasionally found in the muscle of swine. (After Leuckart, 1889, p. 155, fig. 86.) both 2. The Common Liver Fluke (Fasciola hepatica) of Cattle, Sheep, Swine, etc. [Figs. 2-22.] For anatomical characters, compare fig. 3 with key, p. 21. VERNACULAR NAMES. English, Common Liver Fluke; German, Leberegel, Leberwiirm, Schafegel; Dutch, Botten, Levencorm; Dan- ish, Faareflynder; Swedish, Levermask; French, Douve hepatlque, fasciole; Italian, Biscuola, distoma epatico; Spanish, Caracolillo. SYNONYMY. Fasciola hepatica Linnaeus, 1758 ; Planaria latius- cula Goeze, 1782; Distoma hepaticum (Linnaeus) Abildgaard ( ?) ; Fasciola humana Gmelin, 1790; Distoma (Cladocoelium) hepaticum (Linnaeus) of Dujardiu, 1845; Fasciolaria hepatica (Linnaeus) anonymous, 1845; Distomum hepaticum (Linnaeus) Diesing, 1850; Distomum (Fasciola) hepaticum Linnaeus of Leuckart, 1863; Cladocoelium hepaticum (Linnaeus) Stossich, 1892. BIBLIOGRAPHY. For bibliography, see Hassall (1894) and Huber (1894). For more technical discussion of species, see Leuckart (1889, pp. 179-328). GEOGRAPHICAL DISTRIBUTION. Cosmopolitan. HOSTS. Man, cattle, sheep, swine, and other animals. (See pp. 137-143.) 1 For a discussion of these forms, see Stiles, 1894-1895. FIG. 2. The Common Liver Fluke (Faci- olahepatica), natural size (original). 30 INSPECTION OF MEATS FOR ANIMAL PARASITES. Life history. -The life cycle of this fluke, as deter- mined by the in- vestigations of Creplin (1837), Weinland, Leuck- art (1863, 1870 1880, 1881, 1882), and Thomas (1882, 1883), is exceed- ingly interesting; at the same time it is very compli- cated, for the adult parasite, instead of producing young similar to itself and capa- ble of developing directly int o ad ults in cattle, produces eggs which develop into organisms totally different from the adult form living a para- sitic life in other animals. In scien- tific language, the parasite is subject to an alternation of generations, to- gether with a change of hosts. Thefollowing sum- mary of thelifehis tory will make this point clear : (a) The adult her- maphroditic K'0rm(figs. 2 arid 3), the charac- ters of which are given on p. 22, fertilizes it- self (although a cross fertilization of two individuals is not im- possible)^ the biliary FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 31 passages of the liver, ami produces a large number (estimated at 37,000 to 45,000) of eggs. (6) Eggs (figs. 4 and 5). Each egg is composed of the following parts: (1) A true germ cell, which originates in the ovary and is destined to give rise to the future embryo ; (2) a number of vitelline or yolk cells, which are formed in a specialized and independent portion (vitellogeue gland) of the female glands; instead of developing into embryos, the yolk cells form a follicle-like covering for the true germ cell and play an important role in the nutrition of the latter as it undergoes further development; (3) a shell surrounding the germ cell and vitelline cells, aud provided at one end with a cap or operculum. The eggs escape from the uterus of the adult through the vulva, are carried to the intestine of the host with the bile, then pass through the intestines with the contents of the latter, and are expelled from the host with the faecal O ,-e ^ f ...JC FIG. 4. Egg of the Common Liver Fluke (Fasciolahepatica) examined shortly after it was taken from the liver of a sheep ; at one end is seen the lid or operculum, o; near itis the segmenting ovum, e; therest of the space is occupied hy yolk cells which serve as food; all are granular, but only three are thus drawn. X 680. (After Thomas, 1883, p. 281, fig. 1.) FIG. 5. Egg of the Common Liver Fluke containing a ciliated emhrj-o (miraci- dium) ready to hatch out: d, remains of food; e, cushion of jelly-like sub- stance; /, boring papilla; h, eye-spots; fc, germinal cells. X 680. (After Thomas, 1883, p. 283, fig. 2.) matter. Many of them become dried and then undergo no further development, but others are naturally dropped in the water in marshes, or, being dropped on dry ground, they are washed into the water by the rain, or are carried to a more favorable position by the feet of animals pasturing or passing through the fields. After a longer or shorter period of incubation, which varies with the temperature, a cili- ated embryo (miracidium) is developed. At a temperature of 20 to 26 C. the miracidium may be formed in 10 days to 3 weeks; at a temperature of 16 C. the development takes 2 to 3 months; at 38 C. it ceases entirely. Experiments have 32 INSPECTION OF MEATS FOR ANIMAL PARASITES. shown that as long as these eggs remain in the dark the miracitlium will not escape from the eggshell; accordingly it will not escape during the night. When exposed to the light, however, or when suddenly hrought into contact with cold water, the organism bursts the cap from the eggshell, crawls through the opening, and becomes a (c) Free-sivimminy ciliated miracidium (fig. 6). As already stated, this organism is entirely different from its mother. It measures about 0.15 mm. long; it is some- what broader in its anterior portion than in its pos- terior portion ; on its anterior extremity we find a small eminence known as a boring papilla; the exterior surface of the young worm is covered with numer- ous cilia, which by their motion propel the auimal through the water; inside the body we lind in the anterior portion a simple vestigial intestine and a double ganglionic mass, provided with a peculiar pig- meuted double cup-shaped eye-spot; in the posterior portion of the body cavity are found a number of germ cells, which develop into individuals of the next generation. Swimming around in the water, the miracidium seeks out certain snails (Limnaea tnntcatula, L. oahuensis, L. ru- ' bclla, see p. 43), which it im- mediately attacks (fig. 6). The miracidium elongates its pa- pilla and fastens itself to the FIG. 6. Embryo of the Common Liver Fluke (Fasciola hepatica) boring into a snail, x 370. (After Thomas, 1883, p. 285, fl S- 4 -) FIG. 7. Sporocyst of the Common Liver Fluke which has developed from the embryo, and contains germinal cells. X 200. (After Leuck- art, 1889, p. 109, fig. 67 B.) feelers, head, foot, or other exterior soft portion of the body of the snail ; some of the parasites enter the pallial (lung) cavity and attach them- selves there. After becoming securely fastened to the snail the miracidium dis- cards its ciliated covering and shortens to about half its former length (0.07 mm. to 0.08 mm.). The parasites now bore their Avay into the body of the snail and come to rest in the liver, or near the roof of the pallial cavity, etc., the movements gradually cease, and we have before us the stage known as the (d) Sporocyst (figs. 7 and 8). The eye-spots, gauglionic swell- ings, and vestigial intestine become more and more indistinct and are finally lost. The sporocyst grows slowly at first, then more rapidly, and at the end of 14 days or so measures about 0.5 mm. The germ cells mentioned as existing in the posterior portion of the miracidium now develop into individuals of a third generation, known as (e) Rediae (figs. 9 and 10). The rediae escape from the sporo- cyst when the latter are from two weeks (in summer) to four weeks (in late fall) old. Upon leaving the body of the sporocyst they wander to the liver of the snail, where they grow to about 2 mm. long by 0.25 mm. broad. Each redia consists of a cephalic portion, which is extremely motile, and which is separated from the rest of the young Avorm by a ridge; itnder the latter is situated an opening, through which the next generation (cercariae) escape. The posterior portion of the FIG. 8. Sporocyst of the Common Liver Fluke, somewhat older than that of fig. 7, in which the germi- nal cells are giving rise to rediae. X 200. (After Leuckart, 1889, p. 109, fig. 67 C.) FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 33 FIG. 9. Redia of the Commoii Liver Fluke (Fasciola hepatica'/, containing germinal cells which are devel- oping into cercariae. X 150. ( After Leuck- art, 1889, p. 269, fig. 129 A.) worm is provided, at about the border of the third and the last fourths of the body, with two projections. There is a mouth with pharynx situated at the anterior extremity, the pharynx leading into a simple blind intestinal sac. The redia, as well as the sporocyst, may be looked upon as a female organism, and in its body cavity are found a number of germ cells, which develop into the individuals of the next generation, known as (/) Cercariae (figs. 11-13). These organisms are quite similar to the adult parasites into which they later develop. The body is Hat, more or less oval, and provided with a tail inserted at the posterior extremity. The oral sucker and acetabuluni are present as in the adult, but the intestinal tract is very simple; on the sides of the body are seen two large glands, but the complicated genital organs of the adult are not visible. The cercaria leaves the redia through the birth opening, remains in the snail for a longer or shorter time, or passes out of the body of the snail and swims around in the water. After a time it attaches itself to a blade of grass (fig. 12) or some other object, and forms a cyst around itself with material from the large glands, at the same time losing its tail. It now remains quiet until swallowed by some animal. Then, upon arriving in the stomach of a steer, for in- stance the cyst is destroyed, and the young parasite wanders through the gall ducts or, as some believe, through the portal veins to the liver, where it develops into the adult hermaphrodite. From the above we see that this parasite runs through three gen- erations, namely : (1) Ovum, miracidium, and sporocyst first generation. (2) Eedia. . .second generation. (3) Cercaria and adult third generation. During this curious develop- ment, which lasts about 10 to 12 weeks, there is a constant poten- tial increase in the number of individuals, for each sporocyst may give rise to several (5 to 8) rediae, each redia to a larger number (12 to 20) cercariae, and each adult to an enormous num- ber (37,000 to 45,000) of eggs. This unusual fertility of the animal is necessary because of the complicated life history and the compara- tivety small chance any one egg has of completing the entire cycle. 5257 No. 19 3 FIG. 10. Eedia of the Common Liver Fluke, with developed cer- cariae. X 150. (After Leuckart, 1889, p. 270, fig. 130.) FIG. 11. Free cercaria of the Common Liver Fluke, showing two suckers, intestine, large glands, and tail. (After Leuck- art, 1889, p. 279, fig. 137.) 34 INSPECTION OF MEATS FOR ANIMAL PARASITES. Hosts. An interesting and, from an agricultural standpoint, an important matter connected with this fluke is that it is found in a large number (about 25) of domesticated and wild animals, and this fact probably explains to some degree the wide geographical distribu- tion of the parasite. THE EFFECTS OF THE COMMON LIVER FLUKE UPON CATTLE, SHEEP, AND SWINE. This worm is one of the most important and dangerous parasites with which the stock raiser has to deal, since it produces a disease which often results in heavy loss of live stock, especially of sheep. Although it does not seem as yet to have caused any such serious epizootics in this country as have been reported in Europe, sweeping out or greatly retarding the live-stock industry, we should not wait until such an occasion arises before we consider the importance of this subject. We know that F. hepatica is present in the country; furthermore, that it is common in some places (Texas and elsewhere), and we would do well to inquire into the injury which other countries have sustained as a warning that we must not totally ignore its presence among us. The following are among the most important outbreaks 1 recorded: Wernicke (1886) records that not less than 1,000,000 sheep died of fluke disease in the southerly provinces of Buenos Ayres during 1882; in 1886 more than 100,000 head died in Tandil during eight months. Youatt estimated the annual loss in Great Britain at 1,000,000 sheep. For 1879 and 1880, a loss of 3,000,000 head per year was estimated for England alone. During 1876, Slavoiiia lost 40 per cent of her cattle from distomatosis. In 1830, England lost 3,000,000 sheep from this disease, estimated at a value of $20,000,000. In 1829 and 1830, 5,000 of the 25,000 cattle of Montme~dy perished ; in Verdun, 2,200 cattle and nearly 20, 000 sheep, out of 20,000 cattle and 50, 000 sheep, succumbed to the parasite. Names of the disease. The presence of these flukes in the liver of animals gives rise to a disease known under the various names of rot, liver-rot, rot-dropsy, fluke disease, aqueous cachexia, cachexia aquosa verrninosa, fascioliasis, distomatosis, etc. The term rot, as used by farmers and by some veterinarians, is an exceedingly broad one; in many parts of this country almost any dis- ease of sheep is called rot. We have met nodular disease of the intes- tine and other diseases under this term. On this account it must not be supposed that every article on rot refers to liver fluke disease. Symptoms. There is no one special symptom which is characteristic of this disease and absent from all others; in fact liver rot in its various stages might easily be mistaken for other parasitic complaints. (A) The disease in sheep. Gerlach has divided the malady into four periods, and although this division is more or less artificial, since the different stages gradate imperceptibly into each other and are obscured ^or a more complete list of epizootics, see Hassall, 1894. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 35 FIG. 12. Portion of a grass stalk with three encapsuled cercariae of the Common Liver Fluke (Fatdola hepatica). X 10. (After Thomas, 1883, p. 291, fig. 13.) on account of the constant liability to further infection, we give Ger- lach's scheme here as a convenient diagraiu of the disease: These symptoms are taken chiefly from sheep, but the same description applies in a general manner to the same disease in other animals : (1) Period of immigration (stage of traumatic hepatic inflammation, inflammatory swelling of the liver). July to September, lasting about 13 weeks. This is the period of infection, but as the symptoms are not generally very pronounced (the path- ological lesions produced by the flukes not having as yet affected the system of the host) it generally escapes notice. At first a redness of the eyes, which, however, soon disappears ; paleness. Death from apoplexy some- times occurs. The presence of the flukes in the liver irri- tates this organ and causes an increased blood supply (hy- peraemia) and consequent enlargement of the liver. The surface is smooth, marked with small openings, out of which may be pressed a bloody serum, and around these openings there is frequently an inflammation of the peritoneum (localized peritonitis). Gall ducts still about normal; gall more or less bloody ; hemorrhagic centers in parenchyma ; bloody serous exudate in abdominal cavity, in which flukes are occasionally found. No eggs present as yet in droppings. (2) Period of anaemia. September to December, 6 to 12 weeks. The visible mucous membranes (around the eyes, nose, and gums) and the skin are paler than usual. Animals have a tendency to fatten. Appetite may be very good, but after- wards diminishes and rumination becomes irregular; slight oedema; bare skin soft to the touch, loose and pasty; eyes become " fat," i. e., they are partially closed, the conjunctiva becoming puffy ; gradual loss of strength ; fever and accelerated respiration; death in this stage seldom. Liver pale, increased considerably in size, especially in thickness; its capsule rough, opaque; its parenchyma soft with an appearance like porphyry, with hemorrhagic centers; here and there channels caused by parasites; numerous eggs in faeces. (3) Period of emaciation (stage of atrophy of the liver). January to May. Disease is at its height; extreme anaemia and emaciation ; respiration feeble and quickened ; tempera- ture variable; abortions frequent; "puffiness" (oedema) especially frequent under the jaws; mortality high. Atrophy of liver in various stages; gall ducts greatly thickened, frequently with calcareous incrustations ; petechiae beneath endocardium ; bile thick, dirty brown, with numerous eggs. (4) Period of emigration of the flukes. May to July. The flukes leave the liver and are passed with the droppings. The symptoms diminish, but the scars, the result of the inflammatory processes, remain. FIG. 13. Isolated encysted cercaria of the Common Liver Fluke. X 150. (After Leuckart, 1889, p. 286, fig. 142.) 36 INSPECTION OF MEATS FOR ANIMAL PARASITES. Ziindel makes a slightly different division of the periods of the dis- ease, but, as in the division proposed by Gerlach, it is not to be followed too rigidly, as the different periods are not sharply denned from one another. Ziindel's four periods are: First period. Stage of inflammation, inflammatory swelling of the liver : August to October. The presence of the flukes causes an irritation; profuse flow of gall mixed with blood. Generally passes unnoticed. Second period. Stage of contraction of the liver: September to November, 6 to 12 weeks. Flukes collected in groups partially obstruct the bile ducts, whose irri- tated mucosa is thickened; anaemia, cachexia, general weakness, discoloration of the tissues. Third period. Stage of atrophy of the liver: January to March. Cachexia; high mortality. Flukes mature ; gall diicts greatly thickened and hardened. Liver atro- phies in some places, swells in others. Fourth period. Stage in which the flukes leave the liver: April to June. (B) The disease in cattle. The first symptoms are generally over- looked, the disease not attracting attention until the appetite is dimin- ished, rumination becomes irregular, the animals become hidebound, and the coat dull and staring. The staring coat is due to the contraction of the muscles of the hair follicles. The visible mucous membranes become pale, eyes become dull, there is running at the eyes, and the animal gradually becomes emaciated. As the disease advances the milk sup- ply is lessened, fever appears, there is generally great thirst, but the appetite almost ceases 5 oedematous swellings appear on the belly, breast, etc.; diarrhoea at first alternates with constipation, but finally becomes continuous. The disease lasts from 2 to 5 months, when the most extreme cases succumb. Ostertag (1895, p. 357) states that most of the European cattle are infested with liver flukes, but that even when a large number are pres- ent the nourishment of the cattle is not disturbed. Thickening of the gall ducts, so that a so-called "Medusa's head" forms on the surface of the liver toward the stomach, appears in even well-nourished animals; even in cases of a cirrhosis of the liver it is seldom that any effect upon the cattle's health can be noticed, and as long as a portion of the liver tissue, about twice the size of the fist, remains intact the nourishment of the animal may be comparatively good. Ostertag, in all of his expe- rience, has never seen a generalized oedema in slaughtered cattle as a result of fluke invasion, and even in the heaviest infectious of young cattle he has noticed only emaciation. (C) The disease in hogs. The Common Liver Fluke is a compara- tively rare parasite in swine and apparently of very little importance. Pathology. The pathological lesions are directly dependent upon the presence of the flukes in the body, and as the liver is the chief abode of the parasites, we should accordingly expect to find that this organ is more affected than any other, and the seat of the primary lesions; also that the symptoms and changes noticed in other organs are in nearly all cases directly dependent upon the changes in the liver; furthermore, FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 37 that the extent of the lesions is dependent upon the number of para- sites present. The size of the worms and the size of the spines found on them are two important factors in determiuiug the extent of the lesions. By their presence and wanderings in the gall ducts the parasites irritate the mucosa and cause an inflammation accompanied by an increased secretion, leading to a desquamative catarrh ; this inflammation causes a thickening of the mncosa with growth of its glandular elements (glandular hyperplasia) and submucosa. The young parasites make their way into the smaller ducts, rolling their body dor- sully and here singly, or in the larger ducts in groups, they cause a dilatation of the ducts, in some cases forming cysts. There is a hyperplasia of the connective tissue <$-. FIG. 14. Drawing from a microscopic preparation showing a hemorrhage in the parenchyma of the liver caused by the Common Liver Fluke (Fasciola hepatica) : a, atrophic liver tissue ; b, round cell infiltration ; c, a portion of the parasite; d, hemorrhage. (After Schaper, 1890. PI. I, ng. 1.) and a cellular infiltration, together with an increased development of the blood capillaries. The inflammatory process extends from the duct walls to the interlobular connective tissue, accompanied by atrophy of the parenchyma. A slight atrophy of the parenchyma, with an extensive hypertrophy of the connective tissue and an extensive infiltration and increased blood supply, naturally causes an increase in the size of the liver. With the decrease of the hyperplastic tissue and the consequent compression and destruction of the capillaries the cirrhotic and atrophic processes become evident. An advancing hyperplasia of the connective tissue destroys the parenchymatic cells of the lobules, leaving in many cases only a clump of gall pig- ment as evidence of a former lobule. Gradually a smaller or larger portion of the liver is changed into a mass of cicatricial tissue surrounding stiff tubes the meta- morphosed gall ducts. Besides the lesions thus far described, due for the most part to the changes in the gall ducts, other changes are found due directly to the action of the parasites upon the parenchyma of the liver, namely, a breaking down of the liver tissue, paren- 38 INSPECTION OF MEATS FOR ANIMAL PARASITES. chymatic hemorrhages, pus infiltrations, .and abscess formations. The flukes may break through a smaller gall duct, or may penetrate one of the larger ducts at a weak point, and wander directly through the soft glandular tissue; the mechanical injury to the tissue results in its necrosis; blood vessels are also injured, giving rise to multiple hemorrhages, which may discharge through the gall ducts and aid in producing the general anaemia. Inflammation naturally follows the flukes in their wanderings, leading to a liquefaction of the tissue and formation of abscesses, in which bacteria (streptococci and staphylococci) are found, the organisms having ome from the inflamed bile ducts. With this inflammation going on it is but nat- ural that the walls of some of the blood vessels should be aft'ected, thus making it possible for the flukes to gain access to the circulation, with which they might be FIG. 15. Drawing from a microscopic preparation showing the glandular hyperplasia of the mucosa of a gall duct caused by the Common Liver Fluke (Fasciola hepatica) : a, liypertrophied submucosa; 6, interstitial connective tissue; c, compressed lobule; d, lumen of the gall duct; thickened fibrous wall of the gall duct. (After Schaper, 1890, PI. I, fig. 2.) carried to various parts of the body, lungs, brain, etc., causing endophlebitis, end- arteritis, ruptures, thrombosis, emboli, abscesses, etc. ; pyaemic or septicopyaemic processes may extend from the liver, and finally the flukes in their wanderings may perforate the capsule of the liver, causing perihepatitis or peritonitis. These various pathological lesions naturally act upon the circulatory system. The branches of the portal veins and vena cava are compressed or obliterated to a certain extent, and ascites and oedema follow. The bile is greatly changed, becoming more or less thick, greenish brown, or dirty red, and containing epithelial, parenchymatic, and blood cells, leucocytes, bacteria, fluke eggs, etc., according to the processes going on in the liver. The hemorrhages, lack of sufficient gall, consequent disorder in digestion, patho- logical changes, etc., rapidly lead to a general cachexia, weakness, and emaciation. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND WINE. 39 In animals infested with flukes it has been noticed that the blood is poor in haemo- globin and that the number of blood corpuscles is below the normal. For a more detailed discussion, see Schaper (1890). As already stated, the symptoms aud pathology here given are based chiefly upon observations made on sheep, but what has been said of the disease in sheep may also be said of the disease in cattle, except that the latter, on account of their greater strength, can better withstand the attack, aud the symptoms are accordingly not so marked. Diagnosis. Flukes are said to be found in the faecal matter during the fourth stage, but their eggs may be found much earlier. Accord- ingly, if fluke disease is suspected a positive diagnosis may be made by FIG. 16. Drawing from a microscopic preparation showing a flnke in the tissue of the liver: a, necrotic liver tissue ; b, atrophic liver cells; c, spines on the fluke, showing the outline of the body. (After Schaper, 1890, PL III, fig. 5.) a microscopic examination of the faeces to find the ova. In order to do this it is often sufficient to place a minute portion of faecal matter on a slide, add a drop of water, and examine under a low-power lens. An easy method of concentrating the eggs in a given amount of manure to be examined, so that the microscopic examination will be facilitated, is to place the faecal matter in a jar of water, shake well, filter through a wire net, and allow it to settle. The fluke eggs will settle on the bottom with the heavier matter, but a great deal of vegetable material will be caught by the wire netting or will float. The part which floats can then be drained off with water, leaving the eggs in the more solid matter, which can then be examined microscopically. If facilities for a microscopic examination are not at hand, it is best to sacrifice one of the animals of the herd the one in which the symp- toms are most pronounced and examine its liver for flukes. 40 INSPECTION OF MEATS FOR ANIMAL PARASITES. Position of the parasites. For the most part the flukes are confined to the gall ducts; some, however, are found in the parenchyma of the liver; a few reach the portal veins and cause endophlebitis, thrombosis, and emboli; others enter the liver veins and are carried to various parts of the body; upon passing the heart they reach the lungs, where they can give rise to hemorrhagic centers, canals with bloody contents, or even nodules. From the pulmonary arteries they could reach the pul- monary veins, and from there may be carried by the blood to any part of the body. The presence of flukes in peripheral portions of the body is, however, exceptional. Influence of age. It has been noticed in epizootics that calves and cattle under three years are more seriously affected by the disease than are older animals. This is undoubtedly due to the fact that the older animals are stronger, and hence are able to resist more. It has, however, been shown that very young calves are compara- tively rarely infested with flukes (see fig. 17); a fact which is easily understood when we recall that they are, from their mode of life, food, etc., less exposed to the infection than the older animals, which live almost entirely upon pasture, and, taking in a great amount of grass, naturally stand in danger of swallowing a greater number of the cer- cariae. Bulls which are kept close are generally free from these worms. Geographical distribution; fluky years and fluky seasons. This para- site has a very wide distribution, being found in Europe, Asia, Africa, North America, and South America. As a general rule, it can be said that the parasite is found on the lowlands marshes, valleys, etc. but is generally absent from the highlands; and this is in accordance with the facts observed in connection with the life history, for the interme- diate host is a snail which lives in marshes and marshy districts, but is generally absent from the dry highlands. With this same general law of distribution, dependent upon the physical geography of the country, we can correlate two other general statements in regard to the occur- rence of the parasite, and hence of the disease, based upon the humid- ity of the season namely, fluke disease is more frequent in wet years ("fluky years") than in dry years, and fluke disease is more prevalent after the wet months of the year than after the dry mouths. In wet years, namely, in years of heavy rainfall, the overflow of water naturally extends the limits of marshes and carries the snails over a greater area. Furthermore, the ground being more moist, the eggs have greater chances for development, and the infection is thus spread. An idea of the frequency of the parasites during different months of the year may be obtained from an examination of fig. 17. On this chart Leuckart has plotted the animals slaughtered at the Berlin abattoirs during the years 1883-84, according to statistics furnished by Hertwig. The table covers 94,387 head of cattle and 77,848 calves. Of the cattle, FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 41 aoout three-fourths to four-fifths were infested with flukes, and of these 3,428 were so badly infested that their livers were condemned. Of the calves, only 154 livers were condemned. The table shows us that the parasites are present the entire year; also that there are two periods during the year, namely, from October to January (highest in October) and from March to April, in which the \ dan. Feb Mar Apr. May. dun. duly Aug. Sept Oct. Nov. Dec. IUO 93 A A / \ J \ ,53 ft \ / / / ^ s 32 1 \/ Steers. ^Xa an 30 \ \ / x" & 30 V IS s~ ^ r* fg I 44*Wr ^F ^r % dan. "Feb. Mar Apr. May dun. duty. Aug. Sept. Oct. NOV. Dec. / /'\ 13 A /' \ /\ / / ^\ V / / \ 5 J ^-* _^ ^7 -ft- 4 *\ V \_ 3 ,^~ 3 dan. Teb. Mar Apr May. dun. duly Aug. Sept. -Gel. Nov. Dec. ^r A A / \ \ i / \ S ^i \ j^5 . / i i 'H FIG. 17. Tabular diagram of the occurrence of the Common Liver Fluke (Fasciola hepatiea) daring different months of the year: a, cattle; b, sheep; c, swine. (After Leuckart, 1889, p. 301, fig. 147.) livers are particularly infested, or so altered as not to be fit for food. Leuckart has interpreted these figures as signifying that the winter maximum pointed to an infection in the fall, while the summer maxi- mum pointed to one in early spring, namely, during the wettest seasons of the year. 42 INSPECTION OF MEATS FOR ANIMAL PARASITES. According- to Lutz (1892), Oahu and Kauai of the Sandwich Islands suffer considerably from fascioliasis. In some parts of Oahu nearly all the cattle have been destroyed by the disease; the sheep from dry districts, however, are not affected. Of C02 calves examined at Hono- lulu, 298 were found infested; of 2,186 cattle, 1,313 were infested, so that about four-sevenths of the animals were diseased. In this country we have no exact statistics covering this parasite, but Francis, in writing upon the presence of the worm in Texas, states "that it is exceptional to find a liver free from them at any time of the year, and especially so during the spring;" also, that "heifers coming 2 years old suffered more than at any other age. Many of the cattle and sheep die, and many of those that recover do not thrive the following summer, but remain poor and weak and fail to breed." FIG. 18. Limnaea truncatula, natural size and enlarged. (After Leuckart.) Most American authors (Hassall and Francis excepted) have failed to recognize the difference between this species and F. magna, so it is in many cases impossible to determine whether an author had before him F. hepatica or F. magna, or both species, and on this account it is impossible to give the exact distribution of the worms in this country. That it is common in Texas is shown by Francis' article, and I have found the same parasite quite com- mon (August, 1893) in Texan cattle slaughtered at Chicago. I have also found it in other than Texas cattle, although I can not state where the animals came from. Law records F. hepatica from sheep on Long Island. Curtice is of the opinion that F. hepatica is rare in the United States, but says that in sheep it is "reported by sheep books and newspaper articles." Time of infection. Gerlach supposed that the infection takes place only in summer and fall, but the diagram (fig. 17) does not support his view. Furthermore, young flukes have been found in February, pointing to an infection in Janu- ary. Nevertheless, the general rule will hold true that in a temperate climate the time of greatest danger of infection is during the summer and early fall. That the danger of infection gradually decreases in the fall and whiter is shown by the interesting observation of Thomas that in winter the rediae pro- duce other rediae instead of cercariae, and that fluke disease is more fatal to snails than to mam- mals, so that as the season advances the number of cercariae in the fields must reach its maximum and then gradually decrease. In a warm and moist climate the conditions favorable to infection will naturally persist longer than in a cold and dry climate. Source of infection. The snails 1 which form the intermediate host of this parasite must, because of the transmission of fluke disease, be included among the worst enemies of the stock raiser. FIG. 19 Limnaea pere- gra, natural size and enlarged. (After Leuckart.) 1 For a more detailed account, see Stiles, 1894-95, pp. 303-313. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 43 Leuckart and Thomas experimentally demonstrated the truth of Weiuland's view, that in Europe the intermediate host for this fluke is a small swamp snail (Limnaea truncatula}. Leuckart also showed that the rediae (but not the cercariae) would develop in the young of another species of snail (L. peregra), and quite recently Lutz (1892 and 1893) has shown that in Oahu and Kauai (Sandwich Islands) two other snails may serve in this capacity (L. oahuensis Souleyet and L. rubella Lea). In the case of L. oahuensis, Lutz states that " the infection can take place only in young speci- mens." None of these four very closely allied species are recorded for America, and yet we find F. hepatica in both North America and South America, so that we must either have on this conti- nent some other species of snail which may act as intermediate host, or some of the species described in America must be identical with some of the above-named forms. The forms which would especially fall under suspicion are L. humilis Say, in North America, and L. viator Orb., in South America. ^ J. FIG. 20. Limnaea humilis, natural size and enlarged. (After Binney.) FIG. 21. Limnaea oahuensis, natural size and en larged. (After Souleyet.) This report is not the place to discuss the question as to whether these forms ( L. truncatula, L.peregra, L, oahuensis, L. ru- bella, L. humilis, and L. viator) represent six well-established species or not, as that is a matter for conchologists to decide. Suffice it to say that specialists in conchology have described snails under these names; that the forms are all so very closely related that a zoologist would not commit a very grave offense against systematic zoology if he were to consider them as varieties of two or three species; that the forms described under the names L. truncatula, L. oaJiuensis, and L. rubella are known to serve as intermediate hosts for the parasite now under discussion; that in Europe the rediae (but not the cer- cariae) develop in L. peregra, and that it is probable, though not demonstrated as yet, that L. hitmilis is intermediate host for North America and L. viator for South America. Treatment. Hygiene must play a much more important role in the FIG. 22. Limnaea viator, natural size and enlarged. (After d'Orbigny.) treatment of this disease than therapeutics, for while the knowl- edge of the life history of the parasite shows us how we may to a certain extent prevent the disease, no drug is known which can be relied upon to kill the flukes or dislodge them from their habitat. A great many drugs have been tried in the hope of accomplishing this end, but although some authors recommend the use of anthelminthics, most writers admit that such drugs are practically useless in this disease, 44 INSPECTION OF MEATS FOR ANIMAL PARASITES. and that the only treatment practicable is to use stimulants and tonics (various iron salts, walnut leaves, pepper in alcoholic drinks, calamus, etc.), with good nourishing food, such as lupine seeds, lupine hay, roasted malt, linseed cakes, oats, bran, etc., rich in protein, in order to build up the system and carry the animal through to the fourth stage of the disease, when the flukes will die or, as some authorities state, wander out spontaneously; and, in case the pathological lesions are not too great, the live stock will have an opportunity to recover. Many authors recommend astringents and diuretics (salt, juniper berries, tur- pentine, etc.) to meet the hydropic complications. The following are some of the formulae given by various authors for fascioliasis in sheep, and the same medicaments may be used for this disease in cattle : (1) The following is advised by Delafond. Make into a paste with water and allow to ferment, then bake in an oven. Give morning and evening. In about fifteen days this bread is said to produce improve- ment. Mixture. Metric. Approximate equivalents. Avoirdupois . Apothecaries'. Imperial troy. Undressed wheat meal. Oatmeal 1 kilogram . . 2 kilograms. 1 kilogram . . 30 grams 30 grams 200 grams... 2J pounds 2.7 pounds 2.7 pounds. 5.3 pounds. 2.7 pounds. 463 grains. 4G3 grains. 3,086 grains = 6 ounces. Barley meal Sulphate of iron Carbonate of soda . . . Table salt 2| pounds 1 ounce 25 grains . . . 1 ounce 25 grains . . . 7 ounces 24 grains . . f 2.7 pounds 463 grains 463 grains 3 036 grains 6 ounces. The following is Hauber's lick for 100 sheep : Mixture. Metric. Approximate equivalents. Avoirdupois. Apothecaries'. Imperial troy. Sulphate of iron 60 grams 500 grams. .. 20 liters 20 liters 2 ounces 50 grains . . 17 ounces 279 grains. 21J quarts, U. S 21J quarts, U. S 926 grain s = 1.7' ounces. 7,716 grains^l pound 4 ounces. 21 quarts, U. S 2l| quarts, U. S 926 grain 8=1.7 ounces. 7 716 grains 1 pound 4 ounces. 17jf quarts, imperial. 17f quarts, imperial. Roasted harley malt . (3) The following is Hauber's lick for 50 sheep : Approximate equivalen t8. Avoirdupois. Apothecaries'. Imperial troy. 463 grains. Powdered juniper berries. 500 grams. 17 ounces 279 grains . 7,716 grains = 1 pound 4 ounces. 7,716 grains = l pound 4 ounces. 7,716 grains 1 pound Grits 20 liter s... 21J quarts, U. S 4 ounces. 21 J quarts, U. S 4 ounces. 17f quarts, imperial. (4) The following lick for 300 sheep is highly indorsed by some authors, but not considered of much value by Ziirn. A portion of this FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 45 mixture is given every other day for awhile, and then once every fourteen days through the summer. Mixture. Metric. Approximate equivalents. IT. S. apotheca- ries', or wine measure. Imperial troy. Powdered lime 5 liters 10 liters . 5J quarts 4g quarts. 8f quarts. Powdered table salt (5) Mojkowski reports good results in treating sheep twice a day for a week with 0.7 to 1 gram (metric) of napthaliue (=7.7 to 15f grains apothecaries' or imperial troy). (6) Ziiru suggests the following to be mixed and given to cattle in four doses in two days : Approximate equivalents. Avoirdupois. Apothecaries'. Imperial troy. Powdered wormwood . . Powdered calamus root 90 grams.. 90 grams,. 3 ounces 76 grains . . 3 ounces 76 grains . . 1,389 grains = 2.89 ounces. 1,389 grains 2.89 ounces. 1,389 grains = 2.89 ounces. 1,389 grains = 2.89 ounces. 231.5 grains. (7) Bunk advises 30 to 60 grams (=1 ounce 25 grains to 2 ounces 50 grains avoirdupois =463 to 926 grains apothecaries' or imperial troy) of benzine as a daily dose for each steer, to be given in mash. The butcher's knife will be found a much more practicable means of treatment than any of the prescriptions given above, and the earlier in the disease that the animals are slaughtered the better condition they will be found in. In the early stages of the malady, as was seen above, there is a tendency on the part of the animals to fatten, due possibly to the increased flow of bile and the consequent acceleration in diges- tion, and, according to several authors, this fact has been taken advan- tage of by certain sheep dealers who have purposely exposed their flocks to fluke infection in order to fatten them early in the season. In the case of cattle infected with F. hepatica it will scarcely be nec- essary to take such strenuous precautions as with sheep, for, as already stated, the disease is by no means as fatal to cattle as to sheep ; in fact, in the vast majority of cases the presence of the parasites in cattle is not recognized until after the animals are slaughtered. This must not, however, be interpreted as meaning that the disease in cattle may be ignored, but merely that the disease in sheep must receive much more prompt attention than the disease in cattle. If sheep are pastured in the same region as cattle, the presence of this parasite in cattle becomes doubly important, for in this case the disease will be spread to sheep and may cause heavy losses. Prompt measures to suppress the disease and isolation of the infested cattle should accordingly be resorted to. 46 INSPECTION OF MEATS FOR ANIMAL PARASITES. Preventive measures. For an excellent and more detailed account of the preventive measures, the reader is referred to Thomas (1883, pp. 296-305), of which the greater part of the following is a summary: As seen from the life history of the parasite, four conditions are nec- essary for the propagation of this disease in any given district, namely : (1) The presence of fluke eggs; (2) wet ground, or water during the warmer weather, in which the eggs may hatch ; (3) a snail (L. truncatula, or certain other species j which will serve as intermediate host; (4) herbivorous animals must be allowed to feed upon the infected pastures without proper precaution being taken to prevent infection. Destroy anyone of these conditions and fluke disease will be destroyed; con- trol any one of these conditions and the disease will be controlled in equal measure. These conditions may be controlled or held in check by the following means : (1) To prevent the scattering^/ eggs in the fields: (a) In buying cattle or sheep, do not purchase any from a flaky herd, as they may introduce the disease to your farm. (1) If animals are fluked, send those which are most affected to the butcher and place the others on dry ground. (c) Destroy the livers of the slaughtered fluked animals, or if used as food for animals (dogs, etc.,) they should first be cooked in order to kill the eggs ; if this precaution is not taken, the fresh eggs will pass through the intestine of the dogs uninjured and be scattered over fields. (d) Manure of fluky animals should never be placed upon wet ground. It is, however, not dangerous to use such manure upon dry ground. (e) "As rabbits and hares may introduce the disease into a district, or may keep up an infection if once introduced, these animals should be kept down as much as possible." This is not always practicable. (/) Where animals very heavily infested with flukes have pastured on a given piece of ground, some one should go over the field with a spade and spread out the patches of manure, so that it will dry more rapidly, and thus the eggs may be more quickly destroyed. A spade full of lime or dust will aid in drying up the manure patches. (g) Manure of fluky animals should not be stored where it can drain into pastures. (2) To control the second condition, i. e., marshy ground: (d) The marshes should be drained, if possible, so that the snails may be gotten rid of. (&) It has been noticed that sheep which pasture on salty marshes are not fluked ; accordingly dressings of salt, to which lime may be added, should be spread over the pasture, as salt and lime will destroy the embryos, the encysted cercariae, and the snails. May to August are the best months for scattering these substances. Lime will destroy the grass for immediate use, but will in some cases be advantageous to the soil. The farmer must decide for himself whether he should use salt alone or lime and salt. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 47 (c) If the marshy ground can not be controlled, place the animals on higher ground. (3) To destroy the snail. This may be done by draining the fields, thus depriving the snails of the conditions necessary for their develop- ment, or by the free use of salt and lime. (4) General precautions to be taken : (a) It is known that salt will kill the cercariae; accordingly if salt is given to the animals they stand a better chance of escaping hepatic infection, even if the germs are swallowed, not only because this sub- stance kills the young flukes, but because it aids the animals in their digestion. The following experiment is interesting in this connection: A number of uninfected sheep were selected and divided into two flocks, then placed upon pasturage which was known to be infected. One flock received no special attention, while the sheep of the other flock were fed a quarter of an ounce of common salt well mixed with half a pint of oats every day that they were on the pastures; but when fed upon turnips, vetches, etc., the allowance of salt and corn [=oats] was not given. The first flock were so infected with flukes that they could not be kept through the winter, while the second flock was quite sound. The corn [=oats] and salt had cost about 3s. (75 cents) per head; the profit was about 50s. ($12.50) per head. T. P. HEATH, Western Morning News, October 14, 1882. (&) A daily allowance of dry food should be given. (c) If fields are overstocked the animals will be obliged to graze very close to the ground, and will thus be more liable to become infected; accordingly, in order to prevent this close grazing, fields should not be overstocked. (d) Animals should not be left too long upon the same pasture. (e) Eaised watertanks should be placed in the pastures so that the herds will not be forced to drink from pools, etc. As it is difficult for snails to get into such drinking tanks, there will be little fear of infec- tions from tanks of this sort. ABATTOIR INSPECTION. Fluked animals as food. If only a few flukes are found in the liver and these have not caused any extensive pathological changes, there seems to be no valid reason for condemning the entire organ as food, for the eggs would be perfectly harmless if eaten ; the adult parasites, if swallowed alive, might cause some temporary injury, but as liver is well cooked in this country, there is scarcely any chance that the adult worm would be swallowed alive; if the pathological change is confined to a portion of the liver, that portion can be cut out and the rest may be used for food ; in case of a general cirrhosis, or in case of suppurat- ing inflammation of the tissue, caused by the wandering of flukes through the same, the liver should be condemned to the tank. There is generally no particular alteration to be noticed in the flesh of fluked cattle, uuless the livers are very far gone, in which case the meat is more "flabby" and lighter than usual. In the case of badly fluked sheep, the flesh is of a very poor quality and contains but little nour- 48 INSPECTION OP MEATS FOR ANIMAL PARASITES. ishment; it is pale and " flabby," and according to European autnors it should not be placed on the market in case the sheep have passed Gerlach's second stage of the disease. JURISPRUDENCE. In this country we have no general laws protecting a person in case he buys fluked animals. In Germany, Austria, and Switzerland cer- tain laws protect the buyer, so that if fluke disease shows itself in a flock within a stated time after purchase the contract is void. THE COMMON LIVER FLUKE IN MAN. This parasite is rare in man, only about twenty cases being on record of its presence in the bile ducts. It is not at all impossible that the parasites described as Hexatliyridium venarum, Distomum oculi-humani (D.ophthalmobium),a,u CATTLE. [Figs. 25 and 26.] This parasite was originally described by Looss (1896, pp. 33-36, 192) as a variety of the common fluke, but he has recently written to us that he is now inclined to look upon it as a distinct species. He found the parasite in the liver of cattle (Bos taurus) and buffalo (Bos lubalis). Blanchard (1896, p. 733) evidently considers this form identical with both the narrow fluke (F. hepatica angusta) and the giant fluke (F. gigantica, p. 49). (c) THE COMMON LIVER FLUKE (Fasciola hepatica caviae) OF GUINEA PIGS. SYNONYMY. Distomum caviae Sonsino,'lC90; Fasciola hepatica var. caviae (Sonsino) Sonsino, 1896. Sonsino described this parasite from the guinea pig as a distinct species, but he now. believes it to be a variety of the Common Liver Fluke. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 49 3. The Giant Liver Fluke (Fasdola gigantica) of Giraffes, Cattle (?), andMan(?). [Fig. 27.] SYNONYMY. Faaciola gigantica Cob- bold, 1856; Distomum giganteum Dies- ing, 1858; Diatoma hepaticum ex p. of Gervais and van Beneden, 1858; Fasdola giganteaCobbold, 1859; Clado- coelium giganteum (Diesing) Stossich, 1892 ex. p. BIBLIOGRAPHY. For bibliography and technical dis- cussion, see Stiles, 1894-95, pp. 139- 143. HOST. Giraffe, cattle (?), andmaii (?). (See pp. 137- 143. This parasite was described from specimens taken FlG - 25. The Egyp- in England from a tian Liver Fluke . /v. T T . (Fasdola hepatica jnrane belonging 6 8 aegyptiaca), drawn to a traveling men- from one of Loo88 , agerie. Blanchard (1895, p. 733) be- lieves it identical specimens, natural size (original). See p. 48. 5257 No. 19- with the narrow fluke (p. 48) and evidently also with the Egyptian fluke (p. 48). 4. The Large American Fluke (Faa- ciola magna) of Cattle and Deer. [Figs. 28-35]. For anatomical characters, compare figs. 29 and 30 with key, p. 21. VERNACULAR NAMES. English, The Large American Fluke, The Grand Fluke; German, Der grosse amerikan- ische Leberegel; French, Grand Dis- tome; Italian, Distoma grande, Distoma magno. SYNONYMY. Distomum magnum Bassi, 1875; Faaciola carnosa Hassall, 1891; F. americana Hassall, 1891; FIG. 24. The Narrow Liver Fluke (Fateiola hepatica angusta), en- larged to show the anatomical characters : a, acetabulum ; i, in- testine : m, mouth with oral sucker ; o, ovary ; p, pharyngeal bulb ; *, shell gland ; t, profusely branched testicles ; u, uterus ; va, vagina ; vg, profusely branched vitellogene glands. See p. 48. 50 INSPECTION OF MEATS FOB ANIMAL PARASITES. ,m FIG. 26. The Egyptian Liver Fluke (FowetoZa hepatica aegyptiaca), enlarged to show the anatomical charac- ters: a, acetabulum; c, cirrus pouch; i, intestine; m, mouth with oral sucker ; o, ovary ; , shell gland ; t, profusely branched testicles; ut, nterus; va, va- gina; vg, profusely branched vitellogene glands. (After Looss, 1896, PI. Ill, fig. 16.) See p. 48. FIG. 27. The Giant Liver Fluke (Fasciolagigantica), enlarged to show the anat- omy. (After Cobbold, 1864.) See p. 49. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 51 Distomum texanicum Francis, 1891; D. americanum (Hassall) Stiles, 1892; Fasciola magna (Bassi) Stiles, 1894. BIBLIOGRAPHY. For bibliography and technical discussion, see Stiles (1894-1895). HOSTS. Cattle, deer and other animals. (See pp. 137-143.) GEOGRAPHICAL DISTRIBUTION. North America (Texas, Arkansas, Indian Terri- tory, California, Iowa, Illinois, New York, and probably else- where) ; Europe (Italy). The Large American Fluke appears to be more frequent in this country than the so-called Common Liver Fluke, although this opinion is the result of general impression from abattoir inspection rather than a view based upon actual statistics. The para- site was first described by Bassi, who found it pro- ducing a fatal epizootic among the deer of the Royal Park near Turin, Italy, where it is supposed to have been introduced with imported Wapiti from North America. Dinwiddie has found that in some counties of Arkansas practically all the cattle are infected with this worm, and for years the livers of cattle from certain districts have been unfit for use. As the infected area fell within the cattle-fever district, some persons erroneously thought that the changes produced in the liver were due to Texas fever. Fortunately this species (so far as known) does not occur in sheep, and on that account it must be looked upon as of less importance than the common fluke. Leidy (1891) thought this species identical with " Distomum crassum," which occurs in man, and Stossich (1892) considered it identical with the giant fluke Gladocoelium glganteum ( = Fasciola gigantica) of giraffes. Life history. The complete life .his- tory of this parasite has not yet been experimentally demonstrated, but as the species is so closely allied to the Common Liver Fluke, it will un- questionably be found that the life cycle agrees with that given for Fasciola hepatica (p. 30). Upon several different occasions experiments have been instituted in this Bureau to trace out the life cycle, but the snails we have collected FIG. 28. The Large American Fluke (Fas- ciola magna), natural size (original). Flo. 29. Macerated specimen of Large American Fluke, showing the digestive system and acetabulum. X 2. (After Stiles, 1894, p. 226, fig. 2.) 52 INSPECTION OF MEATS FOR ANIMAL PARASITES. in the locality of tbe District of Columbia have thus far not taken the infection. Egg. The eggs (fig. 32) of F. magna can hardly be distinguished from those of F. hepatica. In general, however, they are slightly larger, In F. hepatica they vary from 0.105 mrn. to 0.145 mm. (rarely 0.172 mm.) long by 0.063 mm. to 0.09 mm. broad. In F. magna they vary from 0.109 mm. to 0.168 min.long by 0.075 mm. to 0.096 mm. broad. The structure of the egg agrees perfectly with that given for the Common Liver Fluke, so that a differential diagnosis in faecal examinations is impossible. Upon several different occasions we have raised the Miracidium (figs. 33, 34), which agrees with the cili- ated embryo of F. hepatica (see p. 32). It is covered with a ciliated epithelium, and upon its anterior end is found a papilla in which an opening is perfectly visi- ble. This opening leads into a thin string of tissue, evidently a rudimentary oesophagus, ending in a double-lobed body, which from homology with F. hepatica represents the rudimentary intestine. Im- mediately anterior of this is situated the ganglionic mass with the two cup shaped eye-spots. In the posterior portion of the body a number of germ cells can be distinguished. The movements of this embryo agree with those of F. hepatica. The size varies according to contraction, but in general it may be given as 0.15 mm. long by 0.04 mm. broad. Sporoeyst, redia, and cercaria. For a description of these stages (not yet known for F. magna), see pp. 32 and 33. The disease. The remarks upon this subject on page 36, under F. hepatica, will apply in a general way to this parasite also. The large FIG. 30. Macerated specimen of Large American Fluke ( Faseio la magna), showing the anatomical characters : a, acetabulam; m, mouth with oral sucker; o, ovary; p, pharyngeal bulb ; s, shell gland ; t, profusely branched testi- cles; vg, profusely branched vitellogene glands. X 2. (After Stiles, 1894, p. 236, fig. 3.) FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 53 FIG. 31. A section of the cuticle of Large American Fluke (Faseiola magna), showing the spines. (After Stiles, 1894, p. 227, fig. 7.) fluke appears to be more dangerous for cattle, however, than the com- mon fluke. According to Francis, many cattle die from the effects of the common fluke, and those which recover do not thrive the following summer, but remain poor and weak and fail to breed remarks which if well founded for F. liepatica would apply in a still greater degree for F. magna. Heifers coming 2 years old suffered more than at any other age. It is stated that the large fluke has caused disease among the dairy cows in California, and Francis is said to have investigated an outbreak in Texas where the loss ran into hundreds of cattle. In the Italian outbreak, the disease corresponded with fluke disease of sheep, and reached its highest stage during the winter and spring. Bitting (1895) records fluke disease in cattle for Flor- ida, but attributes it to the common fluke. Symptoms. See remarks under F. hepatica, pp. 34-36. Pathology. The pathological changes brought about by this form have never been studied in detail, but the earlier changes will doubt- less agree with those described for F. liepatica. In heavily in- fected livers there is a much greater tendency to the forma- tion of large cysts in the liver, in which several parasites are present. Dinwiddie has described a post mortem as follows: Apparently in good health and fair butchering condition. The "fat caul" seen on first opening the abdomen as a large sheet was dotted with black spots and streaks. Lymphatic glands on the concave sur- face of the liver were much swollen and black in color. The liver itself large number of vitelline was enlarged and darkened on the cells, and an eggshell pro- ,. .,, , ,. surface, with a number of prominent vided With a cap. (After Stiles, 1894, p. 227, fig. 4. ) elevations, some appearing like blisters and some more or.less solid, and vary- ing greatly in size. A longitudinal section showed the presence of many cavities, some containing a dark fluid in which were floating granules and shreds of tissue. One very large cavity, about 2 inches in diameter, with irregular yellowish colored walls, besides the dark-colored flu id above mentioned, contained FIG. 33. Ciliated em- also two flat, leaf-like bodies about one inch in length and slightly less in breadth. They were fished out and recognized as "flukes." More of these were obtained from other cavities. Several other cavities contained solid, greenish-yellow, gritty matter, and no parasites. A section made through the liver in any direction cut through one or more of these cysts. They were situated near the surface of the organ or in its substance indiscriminately. Those that'contained the "fluke " were usually of medium or smaller size, and the parasite was found folded or curled upon itself longitudinally and surrounded by fluid. * * * The shreds of tissue found in FIG. 32. Egg of Large Amer- ican Fluke, showing the germ cell, surrounded by a b r y o (miracidium) of Large American Fluke withinthe egg- shell. (After Stiles, 1894, p. 227, fig. 5.) INSPECTION OF MEATS FOR ANIMAL PARASITES. those cysts, which did not contain the living paratutes, were shown by microscopic examination to be the d6bris of dead and partly decomposed llukes. Such were the gross appearances of the livers of at least three-fourths of the cattle slaughtered during the spring and summer at this place, and about 90 per cent of all coming from certain ranges in St. Francis and Lee counties [Arkansas]. I am inclined to think that the effects of the para- site upon cattle have possibly been somewhat over- estimated, for I have seen cattle in abattoirs which were apparently in excellent condition and yet whose livers were literally composed almost entirely of flukes and their cysts. The question arises whether other factors (Texas fever, blackleg, etc.) also were not concerned in the outbreaks among FIG 34 Free embryo cattle which have been attributed to this parasite, (miracidium) of Large A small number of these worms certainly has little American Fluke (**- or uo appreciable effect upon cattle, and even when ola magna), snowing ciliated epithelium, bor- a large number is present the effects do not appear ing papilla, rudiinen- to fog very g rea t i n the Case Of full-grOWU Steers. tary oesophagus, and intestine; eye spots sit- The fact that Francis has attributed the death of uated above the g an- a lium ber of cattle (chiefly 2-year-olds) to this worm glionic mass, and germ . . u . AI. -UT-UJ cells. (After stiles, 1S deserving of attention, but the published accounts 1894, p. 227, fig. e.) o f these outbreaks are not detailed enough to allow a satisfactory conclusion. While it must be admitted that the patho- logical changes in the liver of cattle caused by this parasite can not help producing some effect upon the host, we are perfectly war- ranted iu the statement that the Large Amer- ican Fluke bears a much less im- portant relation to the cattle in- dustry than the common fluke bears to the sheep industry. Diagnosis. Same as for the Common fluke. FIG. 35. Cyst in the liver, caused by Large American Fluke. (After Stiles, (See p. 39.) 1894, P . 226, a g . i.) Position of the parasites. Thus far the large fluke has been recorded only in the liver and lungs. Influence of age. The remarks on page 40 under this heading will doubtless be found to hold for the large fluke also. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 55 FIG. 36. Lancet Fluke ( Dicrocoelium lancea- tum), natural size (original). Geographical distribution; fluky years and fluky seasons. F. magna is known from the localities given on page 51. (See also remarks under this head in the discussion of F. hepatica, p. 40.) Time of infection. The remarks under this head on page 42 will apply in a general way to this para- /) site also. " Source of infection. The intermediate host is as yet unknown, but it should not be a difficult matter to deter- mine this point in the iii- fected areas. It will un- doubtedly be found to be a snail, probably of the genus Limnaea. Treatment and preventive measures. See pages 43-47. ABATTOIR INSPECTION. Fluked animals as food. Regarding the flukes in the liver, see page 47. I have ex- amined the meat of a large number of cattle whose livers were infested with this parasite, and have been unable to find any ground for excluding the meat from market. (See also pp. 47-48.) DICROCOELES (Distomes of the Genus Dicro- coelium). One representative of this genus, namely, D. lancea- tum, has been recorded for cattle, sheep, and hogs, and a second species (D. pancreaticum) has been recorded for cattle and sheep, but there is no satisfactory evi- dence that either parasite is present in this country. (See p. 56.) 5. The Lancet Fluke (Dicrocoelium lanceatum) of Cat- tle, Sheep, and Swine. [Figs. 36-39.] For anatomical characters, compare fig. 37 with key, p. 21. FIG. 37. Lancet Fluke, enlarged to show the anatomical charac- ters : a, acetabulum ; c, cirrus pouch; i, intestine; m, mouth with oral sucker; o, ovary; oe, oesophagus; p, pharyngeal bulb; t, lobato testicles; u, uterus; va, vagina; vg. vitello- geue glands. (After Stiles & Hassall, 1894, PI. IV, fig. 19.) VERNACULAR NAMES. English, Lancet Fluke; Ger- man, Der lanzettformige Leberegel, das lanzettfb'rmige Doppelloch; French, Distome lanceole"; Italian, Distoma lanceolato. SYNONYMY. Fasciola lanceolata Rudolphi, 1803 [uec Schrank, 1790] ; Distoma lanceolatum (Rudolphi) Mehlis, 1825; " Distoma (Dicrocoelium) lanceolatum Mehlis" of Dujardin, 1845; " Distomum lanceolatum Mehlis" of Diesing, 1850; "Dicrocoelium lanceolatum Dujardin" of Weinland, 1858; " Fasclola Euchholzii Jordens, 1801," mis- print of Braun, 1889; Dicrocoelium lanceatum Stiles & Hassall, 1896. 56 INSPECTION OF MEATS FOR ANIMAL PARASITES. For detailed tech- (See FIG. 38. Egg of Lan- cet Fluke (Diero- coelium lanceatum) with contained embryo. X 700. (After Leuckart, 1889, p. 379, fig. 171.) FIG. 39. Free embryo (miracidium) of the Lancet Fluke: A, lateral view; B, dorsal view. (After Lenckart, 1889, p. 385, fig. 175 A, B.) BIBLIOGRAPHY. No extensive bibliography as yet published. uical discussion, see Leuckart (1889, pp. 359-399). HOSTS. Man, cattle, sheep, swine, and other animals, pp. 137-143.) GEOGRAPHICAL DISTRIBUTION. Very extended, especially in Europe, but apparently not in England or North America. Life history. The complete development of this par- asite is not yet known, although it is undoubtedly an indirect development with change of host, the inter- mediate host being some mollusk. Von Willemoes-Suhm looked upon Planorbismarginatus as inter- mediate host ; a Limnaea has also been viewed with suspicion. Leuckart found some cerca- riae in a Planorbis, which he suspected fora while repre- sented the larval stage of this worm ; but as none of these snails have as yet been experimentally proven to be the host of the larval stage of the parasite, the question is at present far from being solved. In Leuckart's most recent experiments he has fed eggs of the parasite to certain small slugs and noticed that the embryos escaped from the egg, but were unable to develop into the sporocyst stage. That the embryos escaped from the eggshell in the intestine of slugs points to the fact that the experiments are in the right direction, and that it will proba- bly be fonnd that some snail belonging to the family Limacidae the slugs in the order of the Pulmonata serves as intermediate host to the Lancet Fluke. W/.(( ^&%3\ The Lancet Fluke is much less danger- ous, owing to its smaller size and un- armed cuticle, than either the common fluke or the large fluke; and the path- ological changes caused by the Lancet Fluke, even when present in large num- bers, are scarcely ever more than a ca- tarrhal affection of the gall ducts, rarely with secondary troubles. The parasite is frequently found in very large numbers, cases being recorded where 1,000 speci- mens or more have been taken from a single liver; it may occur alone or in company with F. hepatica. It has been recorded about six times in man. Leidy (1856, p. 43) says that this para- site is " stated to be frequent in sheep in several of the Western States." This "statement" may be correct, but we have not yet been able to verify it. FIG. 40 The Pancreatic Fluke (Dicro- coelium panereaticitm) , enlarged to show the anatomical characters : a, acetabu- lum ; c, cirrus pouch ; ep, excretory pore ; i, intestine ; m, mouth with oral sucker ; ov, ovary ; ph, pharyngeal bulb ; t, testi- cles; u, uterus; va, vagina; vg, vitel- logene glands. (After Eailliet, 1897.) See p. 57. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AMD SWINE. 57 ABATTOIR INSPECTION. In abattoir inspection, the rules given for infection with F. hepatica (p. 47) would apply to cases of infection with the Lancet Fluke. 6. The Pancreatic Fluke (Dicrocoelium pancreaticum) of Cattle and Sheep. [Fig. 40.] For anatomical characters, see key, p. 21. SYNONYMY. Distoma pancreaticum Railliet, 1890; Distoma coelomaticnm Giard & Billet, 1892; Distomum pancreaticum Jauson, 1893; Distoma (Dicrocoelium) coelomaticum Giard & Billet of Rail- liet, 1896; Dicrocoelium pancreaticum (Railhet) Railliet, 1897. BIBLIOGRAPHY. Railliet, 1897, pp. 371-377. HOSTS. Japanese cattle and sheep, Cambodia cattle and- Indian buffalo. (See pp. 137-143.) The Pancreatic Fluke, which is somewhat smaller than the common fluke but larger than the Lancet Fluke, has been found in Japan, Tonkin, and Cochin China, but is not. yet recorded for North America; it is said to be present in about 50 per cent of the cattle and buffaloes of Cochin China, slaughtered in good condition, and in 90 per cent of the cachectic animals; it is found at all seasons of the year, both wet and dry. Its normal seat is the Ductus Wir- sugianus and its branches, which are occasionally given a sausage- like appearance by the presence of the parasites. The local lesions developed by the presence of the Pancreatic Fluke are not gen- erally very extensive; in many cases the pancreas seems quite normal; when the infection is extensive, however, this organ is thicker and heavier than usual; occa- sionally blackish streaks are noticed on the surface, representing the infected canals, but usually it is necessary to cut into the organ in order to recognize an infection. Even when the infected canals assume a sausage-like or moniliform appearance, no abnormal fluid appears to be present, and the thickening and induration of the walls are scarcely noticeable. FIG. 41. Male and female specimens of the Human Blood Fluke ( tichistosoma haematobium) , enlarged. X12. (After Looas, 1896, PI. XI, fig. 107.) See p. 58. 58 INSPECTION OF MEATS FOR ANIMAL PARASITES. There is at present no reason to assume that these parasites would continue to live for any length of time if accidentally eaten by man; ill fact, their direct transmission from cattle to mail through eating sweet- breads infected by them is contrary to analogy. Dioecious Distomes (Flukes of the Subfamily Schistosominae}. BLOOD FLUKES (Distomes of the Genus Schistosoma). Flukes of this genus, only a few of which are known, live in the veins of mammals and birds. At least one species (S. bovis) is found in cattle and sheep, while the occurrence of a second form (S. haematobium) in cattle is as yet in need of confirmation. The Human Blood Fluke has been found twice in this country : once in a foreigner on the " Midway" during the World's Fair, and ouce in New York. 7. The Human Blood Fluke (Schis- tosoma haematobium) of Man and Cattle (?). [Figs. 41-44,48.] For anatomical characters,com- pare figs. 41-43 with key, p. 21. SYNONYMY. Distomum haematobium Bilharz, 1852 ; Schistosoma haematobium (Bilharz) Weinlaud, 1858; Cyiiaecopho- rus haematobius (Bilharz) Diesmg, 1858; Bilharzia haemutobia (Bilharz) Cobbold, 1859; (?) Bilharzia magua Cobbold, 1859 ; Thecosoma haematobium (Bilharz) Moquin-Taudon, 1860; Dis- toma capense Harley, 1864, nomeii nudum; Bilharzia capensis Harley, 1864; Bilharzia haematobia hominis Kowalewski, 1895; (?) Bilharzia hae- matobia mayna (Cobbold) Kowalewski, 1895; Schistosomum haematobium (Bil- harz) of Blanchard, 1895. BIBLIOGRAPHY. For bibliography, see Huber (1894, pp. 294-305). For detailed anatomical study, see Looss (1895, pp. 1-108) and Leuckart (1894, pp. 464-534). HOSTS. Man, Sooty monkey (?), and cattle ( ? ). (See pp. 137-143.) GEOGRAPHICAL DISTRIBUTION. Af- rica. VS, FIG. 42. Anterior portion of male Human Blood Fluke (Schistosoma haematobium), showing theanatomical characters: a, acetabulum; gc, cerebral ganglion ; gl, glands of oesophagus (oe) ; i, intestine ; nda, dorsal anterior nerve; ndp, dorsal posterior nerve; nla, lateral anterior nerve ; nva, ventral anterior nerve ; nvp, ventral posterior nerve ; plv, lateral posterior nerve; pg, genital pore; t, testicles; vs, vesicula seminalis. (After Looss, 1895, PL II, fig. 18.) Life history. The following may be taken as a summary of our present incomplete knowledge of the life history of this parasite. The eggs which are passed in the urine contain a ciliated embryo possessing a terminal papilla; a rudimentary intestinal sac, at each side of which FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 59 is a large glandular cell 5 a rudi- mentary nervous system; an excretory system, and a number of germinal cells. While in the fresh urine the embryo is comparatively quiet, but more active movements can be brought about by the addition of water ; water also causes the shell to burst, the embryo be- coming free ; preserved in urine the embryos die within about two hours. From this embry- onic stage to the time when the parasites are found in the body we have no positive data concerning the life history, although clinical observation and analogy point to unfiltered water as the source of infection. Sonsiiio concluded from his recent investigations that fresh-water crus- taceans (Gammarus Simoni) and in- sects form the intermediate hosts; that the embryo develops through a larval stage ("Dicotyle"), but with- out an alternation of generations, and that man becomes infected by swallowing the "Dicotyle," While analogy points directly to some fresh-water invertebrate as the intermediate host, the presence of germ cells in the miracidium points to a necessary alternation of genera- tions as opposed to Sonsino's idea of a metamorphosis. Hosts. The Human Blood Fluke is found in man in Af- rica, especially in Egypt. A parasite found by Cobbold in the Sooty monkey ( Cercopithe- cusfuliginosus), and described as Billiarzia magna, may pos- sibly be identical with this parasite of man. Cobbold, Leuckart, and Blanchard admit the identity of the two forms, while some other authors do not con- sider the point as yet established. FIG. 43. Anterior portion of female Human Blood Fluke (Schistosoma haematobium), showing the ana- tomical characters: a, acetabu- lum ; i, intestine which is double for some distance, but the two caeca unite (i) back of the ovary ; oe, oesopha- gus ; oo, ootyp ; ov, ovary ; ovd, oviduct; pg, genital pore; g, shell gland; sn, nervous system; ut, uterus; vtd, vitello duct; vg, vitellogene glands. X 38. (After Looss, 1896, PI. XI, fig. 108.) 60 INSPECTION OF MEATS FOR ANIMAL PARASITES. FIG. 44. Egg of Human Blood Fluke (Schistosoma haematobium), with con- tained embryo, passed in the urine. X 285. (After LOOBS, 1896, PL XI, 112.) Schistosoma haematobium has been recorded once from cattle in Cal- cutta, but the determination is perhaps open to question. The exact data given are as follows: Bomford found the peculiar uncinate ova of Bilharzia on microscopic examination of the large intestines of two Calcutta transport cattle de- stroyed on account of their being considered affected with rinderpest. In one case numerous eggs were found in a small portion of the caecum preserved in absolute alcohol. They were most numerous within or between the tubular glands of the mucous membrane, but were also present in considerable numbers in the subuiucous tissue below the muscularis mucosae. The alcohol had shriveled up the con- tents of the eggs, but the external form of the shell was preserved and the characteristic hook very clearly seen. In another bullock the ova were found in some papillomatous growths removed from the margin of the anus. In this case the form of the embryo in the ova could be dis- tinguished. The ova exactly resemble those of Distomum (Bilharzia) haematobium hitherto found only in man (or a monkey), and in Africa, Arabia, or Mauritius. Sonsino's Bilharzia boris of Egyptian cattle differs in the spindle shape of its eggs and in their short, broad, caudate spine. These bullocks had not served in Egypt, but may possibly have obtained the parasites from Indian transport cattle which had done so. This parasite should be sought for in cases of Haematuria of cattle and when the ileocaecal ring is found congested. (See Mem. Med. Officers Army India, II (1886), 1887, p. 53.) 8. The Bovine Blood Fluke (Schistosoma boris) of Cattle and Sheep. [Figs. 45-47.] For anatomical characters, compare figs. 45 and 46 with the key, p. 21. SYNONYMY. Bilharzia boms Sonsino, 1876; Bilharizia crassa Sonsino, 1877; Gynaecophorus crassus (Sonsino) Stos- sich, 1892; Gynaecophorus bovis (Sonsino) Railliet, 1893; Bilharzia haematobia crassa (Sonsino) Kowalewski, 1895; Schistosomum bovis (Sonsino) R. Blanchard, 1895. BIBLIOGRAPHY. For bibliography, see R. Blanchard (1895, p. 191). For anatomical discussion, see Leuckart (1894, pp. 464-534). HOSTS. Cattle and sheep. (See pp. 137-143.) GEOGRAPHICAL DISTRIBUTION. Egypt, Italy, Sicily, India (?). This parasite was discovered by Sonsino (1876) in Egypt in the portal veins of the ox and later he found it in sheep, while Grassi and Eovelli after- ward found it in about 75 per cent of the sheep slaughtered at Catania, Sicily. The sheep were born and raised on the neighboring plains. The worm is said to bring about in cattle and sheep the same lesions of the bladder, intestine, etc., which S. haematobium causes in man. Nothing is known regarding the life history. FIG. 45. The Bovine Blood Fluke (Schittosoma bovis), male and female. X 9. (After Leuckart, 1894, p.467, fig. 204^.) FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 61 THE DISEASE BILHARZIOSIS. As this disease in man has been subjected to much more thorough study than the same malady in cattle and sheep, the human subject may well be taken as basis for the discussion. 1 Source of infection. As already stated, clinical observation and analogy point to unfiltered drinking water as the source of infection. Position of the parasite. The worms are found in the veins of the abdomen, the vena porta, vena linealis, vena renalis, and the venous plexus of the bladder and of the rectum. Symptoms. The period of incubation has not been definitely deter- mined, but Hatch records the case of a patient who remained fourteen days at Suez and suffered from bilharzian haematuria one month after his arrival at Bombay. The young parasites appear to do no injury; in fact, even the adult worms seem to be inoffensive in them- selves. The eggs on the other hand, armed with a sharp point, are the excit- ing cause of the disease. The position of the para- site in the venous system and the consequent loca- tion of the agglomeration of eggs determine the par- ticular symptoms. Either the genitO-Urinary System Fra.46.-Cross section of Bovine Blood Flake (Schistosoma is atticked in Which Case bovis), showing the position of the female in the gynaeco- phoric canal. X 200. (After Leuckart, 1894, p. 472, fig. 209.) haematuria is one of the first symptoms; or the large intestine is attacked and blood is noticed in the stools. If the parasites are lodged in the venous plexus of the genito-urinary system, the chief symptoms are: Haematuria; pains in the lumbar region, the left iliac fossa, the thigh, or in the vulva, which may be spontaneous or may accompany micturition; cystitis; vesical calculus; urinary fistulae; vaginal verminous tumors; nephritis. The eggs accumulate in the capillaries, which they rupture; they traverse the mucosa and fall into the bladder, thus causing more or less hemorrhage ; in this way the haematuria is established, which is often the initial symptom. At first the urine is quite bloody, but it gradually becomes clearer, and it is only at the end of mic- turition that muco-purulent flakes are expelled, in which i. imerous eggs and even embryos are found ; the urine contains also epithelial cells, more or less pus, eggs, and occasionally embryos. On micturition sharp pains are felt at the base of the penis or at the gland, possibly due to the passage of eggs. The passage of eggs 'This discussion is based chiefly upon Blanchard, 1835, pp. 69-93. 62 INSPECTION OF MEATS FOR ANIMAL PARASITES. through the walls of the bladder give rise to cystitis; blood becomes more abundant in the urine after fatigue, coitus, or after taking alcoholics; clots may form and cause retention of urine; chronic urefchritis may develop, evidently due to the pres- ence of the eggs. In Egypt 80 per cent of the cases of vesical calculus coincide with bilharziosts; the formation of the calculi evidently results from the presence of the eggs, for the central nodule always contains one or more of these structures. Urinary fistulae, opening on the perineum, more rarely into the rectum, occasionally form. In women, the vagina may become the seat of a chronic inflammation; it is painful to the touch, exudes a bloody foetid discharge, and may become ulcerated or may be covered with numerous sessile or pedunculate tumors, which are very vascular and spongy, and contain the parasites or their eggs. The mucosa of the vagina, also the uterus and bladder, become impregnated with calcareous salts. Nephritis develops in grave cases. If the parasites lodge in the veins of the rectum the lesions caused are analogous to those described for the genito-uriuary tract; amoug the most prominent symptoms are bloody stools, dys- enteric diarrhoea, enterorrhagia, and prolapse of the rectum. The mucosa is studded with numer- ous papilliform outgrowths, which occasionally attain considerable size and require surgical interfer- ence. The heart, lungs, and liver gen- erally remain normal. Pathology. The bladder is reduced in size, while its wall is greatly thickened, due chiefly to the hypertrophy of the muscularis; the mucosa is also thick- ened, and at certain points it is indu- rated by iiric or calcareous deposits, but the principal lesion consists in ulcer- ations covered with sanious pus; the mucous membrane is infiltrated with numerous leucocytes, but with few eggs ; the submucous connective tissue, how- ever, contains numerous eggs, which also fill the blood vessels; most of the eggs are dead and more or less degenerated ; frequently the mucosa is hypertrophied in places so that papillae are formed which are larger than those found in cases of sim- ple catarrh of the bladder; they occasionally attain a finger in length, and may be recognized during life by cystoscopic examination. Harrison noticed in four cases out of five at Alexandria, Egypt, that the tumors developed in the tissue of the bladder had a carcinomatous character. Lesions analogous to those of the bladder are also observed in the lower third of the ureters and may extend as high as the kidney ; the ureter is enlarged and tortuous ; the mucosa irregular ; its lumen may remain nearly normal in size, but its wall becomes very thick. The flow of the urine may be obstructed. The kidney increases in size, its calyx dilates, the division between cortical and medullary substance becomes indistinct, and the renal tissue may be reduced to an almost homogenous layer 3 to 4 mm. thick; miliary abscesses form on the vsurface ; in short, a veritable hydronephrosis obtains, which results m atrophic FIG. 47. Eggs of Bovine Blood Fluke (Schistosoma bovis), showing the peculiar process on the end: o, 6, layers of the oviduct; c, eggs in the oviduct X 180 ; x, eggs deformed by pressure ; y, spinous process on end of egg X 700. (After Sonsino.) FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 63 lesions of the kidney and may finally end fatally ; death may occur rather frequently from albuminuria; in the less grave cases the renal affection consists of a simple inflammation and pareuchymatous nephritis ; renal calculi may form ; the organ may become the seat of a more or less intense cirrhosis. The vesicula seminalis and prostata may also contain eggs, and become more or less hypertrophied. The polyps of the rectum, mentioned above, may attain 10 mm. to 13 mm. in length ; the eggs are accumulated, especially in the mucosa, and may form masses 1.25 mm. thick, visible to the naked eye; a microscopic examination of the growths shows that they are composed in great part of mucosa, the glands (the normal length of which is about 0.5 mm.) becoming 2 to 3 or 3.5 mm. in length by60/u to80/* in diameter. Between the polyps the mucosa shows the lesions of chronic dysentery; all the tunics exhibit traces of a slow phlegmatic process ; the submucosa is infiltrated with leucocytes; the muscularis may hypertrophy to three or more times its normal thickness. The meseuteric lymphatic glands may hypertrophy, their substance becoming tumitied, presenting small hemorrhagic centers, and containing eggs. The liver may contain eggs and become somewhat cirrbotic ; the eggs accumu- late in the branches of the portal veins, or after piercing the walls they lie in the hepatic parenchyma. The lungs may also contain eggs, as was shown by Mackie in the case of a patient who succumbed to pyemia following a purulent cystitis. He found in the lungs a large number of small metastatic abscesses limited by a necrotic tissue and containing a sanious pus with Schistosoma ova. Diagnosis. The diagnosis may easily be made by a microscopic examination of the urine to determine the presence of the egg. Prognosis, etc. The severity of the disease varies directly with the number of parasites (and hence the number of eggs) in the body. Fortunately, in the majority of cases the number of parasites is small, though it may increase from repeated infections to 500 or more. In cases of comparatively light infec- tion, the disease is reduced to a slight chronic cystitis, with now and then exacerbations, in course of which a slight amount of blood and pus is passed in the urine. The disease may last for years without ap- parent increase. In the most severe cases death may occur from various causes; a rupture of the bladder, ascending pyelonephritis, uremia, albuminuria; the patient may die in marasmus, being exhausted by the dysentery or the anaemia. Bilharziosis is accordingly not such a fatal disease as has sometimes been supposed. Prevention. Avoid unfiltered or unboiled water in contaminated districts. Treatment. No experiments in treating cattle for this disease have been recorded. In human practice Fouquet seems to have had good success with capsules of extract of male fern; he begins with one capsule per day, afterward increasing the dose to two or in some cases to three capsules. The dosing is continued with per- si stency until the patient seems recovered ; the dose is then reduced to one capsule daily Fio. 48. Ureter of an Egyptian, with nu- merous uric-acid con- cretions, as a resultof blood-fluke infection. (After Lenckart, 1894, p. 528, fig. 231.) 64 INSPECTION OF MEATS FOR ANIMAL PARASITES. for one month. Intravesical injections of bichloride of mercury 1:5000 are advised in severe cases. Nitrate of silver, carbolic or boric acid are also used as injections or enemata. Napier claims good results with salicylate of soda; 40 grains before retiring. Surgical intervention is occasionally neces- sary in cases of severe lesions. ABATTOIR INSPECTION. At present the blood flukes do not play any role in tbe inspection at American abattoirs. Should the parasite appear in this country it will probably first be found in Southern cattle, and the affected organs should be condemned in order to prevent the spread of the worm. There would, however, be no danger of trans- mission of the parasite from cattle direct to man. Fio. 49. Conical amphistomes (Amphiitoma cervi) in the ru- men; tubercles from which the parasites have loosened. (After Railliet, 1893, p. 376, fig. 249.) AMPHISTOMES (Flukes of the Family Amphis- tomidae). Of this family of worms, characterized by the position of the acetabulum in the posterior portion of the body, only one species (Amphistoma cervi) has as yet been recorded iii the herbivorous animals of North America. TRUE AMPHISTOMES (Flukes of the Genus Amphistoma). 9. The Conical Fluke (Amphistoma cervi) of Cattle and Sheep. [Figs. 49-55.] For anatomical characters, compare figs. 49 and 50 with key, p. 21. SYNONYMY. Festucaria cervi Zeder, 1789; Fasciola cervi (Zeder) Schrank, 1790; Fasciola elaplii Gmelin, 1790; Monostoma elaphi (Gmelin) Zeder, 1800; Monostoma conicum Zeder, 1803; Amphistoma conicum (Zeder) Rudolphi, 1809; Amphistomum conicum (Zeder) of Diesing, 1850; Strigea cervi (Zeder) Railliet, 1893. BIBLIOGRAPHY. For bibliography, see Otto (1896, pp. 97, 98). For technical discussion, see Otto (1896), Looss (1896, pp. 32, 33, 185-191), and Leuckart (1894, pp. 448-464). HOSTS. Cattle, sheep, deer, and other ani- mals. (See pp. 137-143. ) GEOGRAPHICAL DISTRIBUTION. Europe, Af- rica (Egypt), Asia, Australia, Canada, and probably elsewhere. Life history. Sonsiuo found in an Egyptian snail a larval parasite ( Gercaria pigmentata) which, according to some authors, represents the larval stage of this amphistome. The life cycle has recently been experimentally demonstrated by Looss (1396), who describes it as follows. FIG. 50. Dorsal view of a Conical Amphis- tome, showiugtheanatomicalcharacters : a, position acetahulum ; ex, terminal ves- icle of excretory system; i, intestinal caeca; Lc, Laurer's canal; oe, oesopha- gus ; ov, ovary ; ph, pharynx ; t, testicles ; , uterus; vd, vas deferens; vdt, vitello duct; vs, vesicula seminalis. X5. (After Otto, 1896, p. 100, fig. 4.) FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 65 The eggs escape from the host with the faeces. After a time, evidently varying with the temperature (twelve to fourteen days at 22 C.), a ciliated embryo is formed (fig. 51). This embryo (miracidium) escapes from the eggshell only when exposed to light and in case the water is not below 15 C. Swimming around in the water it enters certain snails (Physa alexandrina Bourg. and P.micropleura Bourg.) establish- ing itself in the visceral cavity. Here it develops into a sporocyst (fig. 52) which, when about fifteen days old, measures 0.7 mm. long by 0.15 mm. broad; a generation of rediae (fig. 53) develops in the sporocyst; the rediae escape from the latter in about fifteen days; a second generation of rediae (fig. 54) forms Avithin the first rediae, escaping by the birth opening; a third generation of rediae may develop within the second. The cercariae (fig. 55) form in the rediae and are born at an early stage of development; when fully developed these cercariae escape from the snail and swim around in the water. The entire cycle to this point is evidently completed in less than two months. The cercaria (Cercaria pig- mentata) is oval, 0.5 mm. long by 0.33 mm. broad with a tail about 0.9 mm. long; body opaque, due FIG. 51. Dorsal view of the free em- p IG . 52 Sporocyst of the Conical Amphistome result- bryo (miracidium) of the Conical ing f rom the transformation and development of Amphistome (Amphistoma cervi) the embryo, age about 15 days : ex. p, excretory pore, about to enter the intermediate g g t matrix of germ cells. The large balls of cells host: /Z, end portion of excretory represent developing rediae of the next generation, system; g, germ cells; gg, matrix X170. (After Looss, 1896, PI. XII, fig. 126.) of germ cells ; i, rudimentary intes- tine; sn, nervous system. X285. (After Looss, 1896, PI. XII, fig. 125.) to pigment and to certain subtegumentary cells; oral sucker spherical, 45 /J. in diameter; acetabulum 90 n in diameter; two eye-spots present. The cercariae encyst themselves on plants and various other objects and evidently gain access to the final host (cattle, sheep, etc.) through the drinking Avater. The Conical Fluke seems to have a very wide distribution, being recorded in Europe, Asia, Africa, North America, and South America. As yet it has not been recorded in the United States, but specimens collected in Canada have been sent to us by Professor Wright, and we may expect to find the same worms any day in the United States. 5257 No. 19 5 66 INSPECTION OF MEATS FOR ANIMAL PARASITES. There is considerable difference of opinion among authors as to whether these parasites are injurious to the animals in which they occur. While some writers state that they are absolutely harmless, others claim that they cause an irritation in the stomach, and that cattle which are heavily infested with them gradually emaciate. According to an Australian paper, the parasites cause a considerable number of deaths among the cattle of the coast districts; they occur in great numbers and injure cows more than steers or oxen. Attach- ing themselves to the mucous mem- brane of the stomach, by means of their suckers they raise the epithelium in form of papillae. The treatment is the same as for adult tapeworms (see p. 133). ABATTOIR INSPECTION. The amphistomes of cattle are of no importance in meat inspection, as they are not transmissible to man in any stage of their development. In fact, ac- cording to Schwein- furth, these parasites are collected by the natives of Africa and eaten raw. Several other am- phistomes are found in various allied ru- minants used for food in certain countries, and although these parasites have not yet made their ap- pearance in this country, we can not tell what moment we shall find them introduced, perhaps with animals imported for menageries. Should they be introduced in this manner and find the conditions necessary to the development of their larval stages, they would, in all probability, develop in our American cattle. As this day has not yet come, they will sim- ply be mentioned here by name and figured. For anatomical charac- ters, compare the figures with the key on page 21. FIG. 53. Adult redia of the Conical Am- phistome (Amphistoma cervi) of the first generation, thirty-nine days after the infection of the intermediate host with embryos: fl, end portion of excretory system ; gg, matrix of germ cells ; t, rudi- mentary intestine; pg, birth opening; sn, nervous system. (After Looss, 1896, PI. XII, fig. 129.) FIG. 54. Young redia of the Conical Amphis- tome of the second generation in which the cercariae develop. X170. (After Looss, 1896. PL XII, fig. 130.) FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 67 10. l Amphistoma erplanatum Creplin is described from the liver and gall bladder of the zebu; von Linstow (1878, p. 49) cites it as a parasite of cattle; Railliet cites it from the Indian buffalo and the zebu. 11. * Amphistoma bothriophorum Braun (fig. 56) also occurs in the stomach, of the zebu. 12. Amphistoma tuberculatum was reported by Cobbold (1875, p. 819) from the intestine of the Indian oxen ; but no descrip- tion of the parasite has ever been given, so that the form may be ignored. 13. 3 Gastrothylax crumenifer Creplin. This parasite (figs. 57-62) is said to occur in most of the bovine animals (the zebu) killed at Son-Tay; its natural habitat is the stomach, and when present in large numbers they irritate the mucous lining and lead to an extreme emaciation of their host. The same parasite was once found at Leipsic, Germany, in a cross between the zebu, gayal, and yak; and von Linstow (1878, p. 49) cites it among the parasites of cattle. 14. 4 GastrothijJa.1- Cobboldii Poirier (fig. 63) was described from the stomach of the gayal from Java. 15. 4 Gastrothylax elongatum Poirier (fig. 64) was described from the stomach of the gayal from Java, and Railliet (1893, p. 379) reports that it has been found in Paris in the stomach of a zebu. 16. 5 Gastrothylax gregarius Looss (figs. 65 and 66) is found in enormous numbers in the rumen of nearly all the Indian buffa- loes slaughtered in Alexandria, Egypt. In one buffalo Looss counted 1,758 specimens on a portion of the mucosa as large as a hand. They were often found associated with Amphistoma cerri. 17. 4 Homaloijaster paloniae Poirier (fig. 67) is found in the caecum of the gayal in Java. 18. 6 Homalogaster Poirieri Giard & Billet is found in the large intestine of Tonkin cattle (=? the zebu). It fixes itself by means of the acetabulum to the mucosa and is sometimes present in large numbers. 1 For original description, see Creplin, 1847, pp. 34 and 35. 2 For technical discussion, see Otto, 1896, pp. 101-105. 3 Amphistoma crumenifer urn Creplin, 1847; Gastrothylax crumeniferttm (Creplin) Poirier, 1883; G. crumenifer (Creplin) Otto, 1896. For bibliography and technical discussion, see Otto, 1896, pp. 94-97. *For technical discussion, see Poirier, 1883, pp. 73-80. 5 For technical discussion, see Looss, 1896, pp. 5-13, 170-177. 6 For original description, see Giard & Billet, 1892, pp. 614 and 615. CLr- FIG. 56. Amphigtoma bothriophorum: a, posi- tion of acetabulum ; ex, terminal vesicle of excretory system; i, intestinal caeca; Lc, Laurer's canal; oe, oesophagus; ov, ovary; ph., pharynx; t, testicles; , uterus; vd, vas deferens. X5. (After Otto, 1896, p. 102, fig. 5.) FIG. 55. Mature cerca- ria of the Conical Am- phistome (Amphistoma cervi), the stage which gains access to cattle andsheep. X75. (After Looss, 1896, PI. XII, fig. 133.) See p. 65. 68 INSPECTION OF MEATS FOR ANIMAL PARASITES. FIG. 57. Enlarged dorsal view of Oastrothylax cntmenifer. (After Creplin, 1847, PI. II, fig. 1.) See p. 67. TAPEWORMS, OR CESTODES (Order Cestoda). [Segmented Tapeworms (suborder Tomiosoma). Tapeworms without four re- tractile probosces (tribe Atrypanorliyncha). Tapeworms with four suckers (subtribe Tetrasaichiona).] Family TAENIIDAE. Ill cattle aud sheep we find both of the stages of tapeworms men- tioned on page 21, namely: Larval forms (cystic worms, bladder worms, hy datids) which live in the muscles or parenchymatons organs, but not in the intestine. They render the meat unfit for food since they are transmissible (ac- cording to the species) to man and dogs; and Adult worms (tapeworms, stro- bilae) which occur in the intes- tines of sheep aud cattle (rarely in the ducts of the liver of sheep) and are not transmissible to car- nivorous animals. Hogs on the other hand appear to be infested only with larval tapeworms, although three isolated cases of adult tapeworms have been recorded for them. These three cases may have been accidental occurrences, the hogs having possibly become acci- dentally infested with worms which normally live in other animals. Tapeworms of the family Taeniidae pos- sess the following characters: The anterior extremity is repre- sented by a more or less knob-like portion known as the head; this is followed by an unsegmented portion, the neck ; head and neck together form the scolex; this in turn by the segments, or proglottids. The head is provided with four cup-shaped suckers, which are neA r er provided with hooks iu any form known in cattle, sheep, or hogs, but are armed with numerous hook- lets in some of the forms found iu certain other animals (man, rabbits, birds). The apex of the head is provided with a muscular body, which develops into different forms in the various subfamilies. It may form a rostellum, which may be unarmed (Taenia saginata) or armed (Taenia solium). In the larval forms discussed in this paper (Taeniinae) the rostellum protrudes at the center of the apex, but in some other forms (Dipylidiinae) it may retract into a rostellum sac. In the adult tapeworms (Anoplocephalinae) of cattle, sheep, etc., the muscular body is composed of stellate fibers which move the suckers, but these fibers do not appear to form a true rostellum. The neck is very simple in structure, containing each side two longitudinal canals and a longitudinal nerve trunk. At the posterior portion of the neck, seg- ments form by transverse division. The segments increase iu size, gradually becoming larger the farther they are from the head; reaching a maximum breadth, they decrease in width, and then increase in length more rapidly. The anterior segments are the youngest, the posterior seg- FIG. 58. Enlarged ven- tral view of Gastrothy- lax crumenifer: a. ace- tabulum; vp, openi to the ventral pouch. (After Creplin, 1847. PI. II, fig. 2.) Seep. 67. FIG. 59. Enlarged view of anterior extremity of Gas- trothylax crumeni- fer: in, mouth; vp, opening to ventral pouch. (After Creplin, 1847, PI. II, fig. 4.) See p. 67. FIG. 60. Enlarged view of posterior extremity of Gax- trothylaxcrummi- fer. See p. 67 FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 69 Fid. 61. Enlarged view of Gastrothylax eru- menifer, with ventral pouch open : a, acetab- ulum ; gp, genital pore ; m, mouth. (After Creplin, 1847, PL II, fig. 5.) See p. 67. ments the oldest. Many zoologists look upon the entire tapeworm as a colony of animals, each separate segment representing a single individual, and all segments being descended from a single animal represented by the head and neck. Owing to their parasitic life, tapeworms are very degraded in their structure. The digestive tract is entirely absent, the worms taking their nourishment by osmosis through their entire surface. The nervous system is composed of nerve centers (ganglia), situated in the head, and two large lateral nerves, one of which extends on each side of the worm from the head to the posterior end of the strobila; in some cases, at least, the lateral nerves are connected by two transverse nerves at the distal end of each seg- ment. The excretory system consists of two dorsal and two ventral longitudinal lateral ca- nals, which are connected in various ways in the head; the ventral canals are connected by transverse canals at the posterior border of each segment. The genital organs form by far the most important organ system in the animal. In the first place, the entire genital system is repeated, so that each segment as it arrives at a given age possesses its own genital organs, independent of the organs of the other seg- ments. Again, every segment is hermaphro- ditic, containing both male and female organs, and in some genera the segments are doubly hermaphroditic, contain- ing double sets of male and of female organs. The male organs consist of a cirrus (penis), a cirrus pouch, a vas deferens, and numerous testicles. The female organs consist of a vulva, a vagina, an ovary, a vitellogene gland, a shell gland, ovi- ducts,andauterus. Each segment possesses one or two genital pores, the cirrus and the vulva of any given set of organs (except in the genus Amabilia, according to Diamare) opening at the same pore. In some species, so-called interproglottidal glands of unknown function are found between the segments. Life history. Tapeworms pass through three stages of de- velopment, known as the oncosphere (or embryo), the larva (a bladder worm known as a cysticercus, a coenurus, an echinococcus, or a cysticercoid), and an adult form known as the strobila. A change of liost is necessary for their development; the host in which the oncosphere develops into the larva is known as the intermediate host, FIG. 62. Dorsal view of Gastrothylax cru- menifer, magnified to show the anatomical characters: a, acetabulum; ex, terminal vesicle of excretory system ; i, intestinal caeca ; Lc, Laurer'a canal ; oe, oesophagus ; ov, ovary; ph, pharynx; t, testicles; u, uterus; vd, vas deferens. X5. (After Otto, 1896, p. 96, fig. 3.) See p. 67. Fro. 63.Gagtrothylax Cobboldii, lateral view : a, acetabulum; i, in- testine ; m, mouth ; vp, opening to ventral pouch. (AfterPoirier, 1883, PI. II, fig. 36. Taken from Braun, Venues, PI. XVIII, fig. 2.) Seep. 67. 70 INSPECTION OF MEATS FOR ANIMAL PARASITES. while the animal which harbors the adult form is known as the final host. The life history of Taenia saginata given on page 72 may be taken as typical for the family. All of the larval cestodes of cattle, sheep, and swine belong to the subfamily Taeniinae, while all the adult forms found in these hosts are classified in the subfamily Anoplocephalinae. Hard-shell Tapeworms (Cestodes of the Subfamily Taeniinae). The Hard-shell Tapeworms, so called because of the thick striated eggshell (embryophore), are found as adults in the intestines of meat- eating mammals, while their larval stage is found in the muscles or parenchymatous organs of herbivorous and om- nivorous animals. These larval forms are very im- portant from the standpoint of meat inspection, and organs which harbor them should be excluded from the market or should be rendered wholesome before being placed on sale. The larval forms may be of three kinds, as follows : (1) Cysticercns (figs. 68 and 70). This is the most simple form. The parasite consists of a cyst, which is in vaginated at a given point. There is normally only one invagination to each cyst, and at the base of the invagination is situated the head of the future tapeworm. Besides the invagina- tioii, the cyst contains more or less liquid. (2) Coenurus (tigs. 99 and 100). In this case there is a considerable number of invaginations, each containing a head. (3) Echinococcus (fig. 105). In the third type there is no invagiuation of the cyst wall, but brood capsules are formed from the parenchyma of the cyst and several heads are formed in each brood capsule. FIG. 64. Oastrothylax elon- gatum: g, ganglion; i, in- testinal caeca -,ph, pharyn- geal bulb; t, testicle; u, uterus; t)d, vas deferens (ductus ejaculatorius) ; ve, vasa efferentia; vg, vitel- logene glands. (After Poirier, 1883, PI. II, fig. 26. 1'aken from Braun, Vermes, PI. XVIII, fig. 7.) See p. 67. Attempts hare been made to subdivide the Taeniinae into genera and subgenera, the genus Taenia Linnaeus being retained for the forms which possess a Cuslicercus or a Coenu- rus as larval form, while Echinococcifer Weinland, 1861, has been proposed as the generic name for Taenia echinococcns. This generic division has not been accepted by the majority of helminthologists, most workers preferring to recognize only one genus, Taenia, but many authors admitting three subgenera, corresponding to the three types of larvae. HARD-SHELL TAPEWORMS (Genus Taenia). The following species of this genus must be considered in this report: Adult. Larva. Name . ! Host. Name. Host. Cattle. Swine and man. Taenia marginata Dogs Taenia co enur us Dogs Taenia echinococcus ! Dogs Cysticercns tenuicollis Coenurus cerebralis Echinococcus polymorphus Cattle, sheep, and swine. Cattle and sheep. Cattle, sheep, swine, man etc. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 71 19. Beef Measles (Cysticercus bovts) of Cattle, and its adult stage, The Unarmed, or Beef Measle, Tapeworm (Taenia saginata) of Man. [Figs. 68-74.] LARVAL STAGE (Cysticercus bovis). For anatomical characters, compare fig. 68 with key, p. 21. SYNONYMY. Cyaticercus Taeniae saginatae Leuckart, 18 ( ?) ; C. bovis Cobbold, FIG. 65. Dorsal view of Gastrothylax greijarius: i, intestinal caeca ; os, oral sucker; ov, ovary; t, testicles; u, uterus; vg, vitellogene glands; vs. vesicula seminalis. X9. (After Looss, 1896, fig. 1.) See p. 67. FIG. 66. Lateral view of Gastrothylax grcgariuf: gp, genital pore; i, intestinal caeca; m, mouth; Lc, opening of Laurer's canal; ov, ovary; pe, excretory pore; t, testicle; u, uterus; vd, vas deferens; vp, ventral pouch; vg, vitellogene gland; vs, vesicula seminalis. X9. (After Looss, 1896, fig. 2.) Seep. 67. 1866; C. Taeniae mediocancllatae Knoch, 1868; C. inermis of various Germans and others, 18 (?); " Cysticerkus" bovis of Schneidemiihl, 1896. HOSTS. Cattle, Rocky Mountain " antelope," llama, and girafi'e. (See pp. 137-143.) ADULT STAGE (Taenia saginata (Goeze, 1782) ). For anatomical characters, compare figs. 69-73 with key, p. $4. SYNONYMY (see also pp. 89-90). Taenia solium Linnaeus, 1758, pro parte; T. cucur- bitiiia Pallas, 1781, pro parte; T. cucurbitina Art [=var.] saginata Goeze, 1782; T. cucurbitina, grandis, saginata Goeze, 1782 ; T. aoliiaria Leske, (1785), pro parte ; Halysis 72 INSPECTION OF MEATS FOR ANIMAL PARASITES. solium (Linnaeus) Zeder, 1803, pro parte; Pentastoma coarctata Virey, 1823; "T. den- iata" Nicolai, (1830) [nee Batsch, 1786] ; "T. lata" Pruner, 1847 [nee Linnaeus, 1758] ; Botlmoceplialus tropicus Schmidtmiiller, 1847; T. mediocaneUata hominis, sen T. medio- canellata seu T. zittaviensis Kiichenmeister, 1852; T. solium var. mediocanellata (Kiichennieister) Diesing, 1854; Taenia- rhynchm mediocanellata (Kiichenmeister) Weinland. 1858; (?) Taenia solium var. abietina Weinland, 1858; T. inermis Moquin- Tandon, 1860; T. mediocancellata (-?-), date (?),see Moquin- Tandon, 1860; T. tropica (Schmidtmiiller) Moquin-Tandon, 1860; T. megaloon Weinland, (1861); T. (Cystotaenia) medio- canellata of Leuckart, 1863 ; T. saginata (Goeze, 1782) of Leuck- art, 1867; (?) T. abietina Weinland of Davaine, 1873; T. iner- mis Laboulbene, 1876; T. algerien, Redon, 1883; (?) T. solium var. minor Guzzardi Asmundo, 1885; T. algeriensis Brauu, 1894 (= T. algerien Redon renamed). ANOMALIES. (?) "Taenia rtilgaris" Werner, 1782 [nee Lin- naeus, 1758] = T. dentata Batsch, 1786; (?) T. fenestrata Chiaje, 1833; T. capensis Moquin-Tandon, 1860; T. lophosoma Cobbold, 1866; T. fusa, T.continua, T. solium f usa seu continua Colin, 1876; T. mummificata Gu/zardi Asmundo, 1885; T. nigra Davaine, 1877; T. inermis fenestrata Maggiora, 1891. PRK-LINNAEAN NAMES. Vermis cucurbitinus composing Tae- nia longissima Plater, 1609; Lumbricus latus Movfetus, (1634); Taenia secunda Plateri Ernst, 1659; Lumbricits latns Tyson, 1683; Solium on Te'nia sans tpine Andry, (1700) ; Taenia de la seconde espece Andry, 1718; Taenia sans epine ou Taenia de la premiere espece Andry, 1741. BIBLIOGRAPHY. For bibliography, see Huber (1892). For technical discussion, see Leuckart (1880, pp. 513-616) ; R. Blanchard (1886, pp. 315-382) . HOST. Man. Life history. Starting with the adult tapeworm (tig. 69) in the intes- tine of man, the life history of the parasite, the knowledge of which we owe to Rudolf Leuckart, is as follows: The eggs (fig. 74) escape from the uterus and are passed with the excreta, or the segments con- taining eggs break loose from the tapeworm and either wander out of the intestine of their own accord or are passed with the excreta. In either case the eggs become scat- tered upon the ground or in water, and reach the cattle through their drinking water or with the fodder. When whole segments (generally several together) are passed, these crawl around on the ground or herb- age, and cattle by swallowing them . FIG. 67 . Homalo g aster paloniae, ventral view. (AflerPoirier, 1883, PI. II, fig. la. Taken from Brann, Vermes, PI. XVIII, fig. 3.) See p. FIG. 68. Section of a beef tongue heavily infested with beef measles, natural size (original). may become infected with numerous eggs at the same time. Upon arriv- ing in the stomach, the eggshells are destroyed ; the embryo then bores its FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 73 way through the in- testinal walls with the aid of its six minute hooks, and wanders to the muscles where it comes to rest; or if it bores into a blood vessel, it may be car- ried with the blood to any organ of the body. When the embryo comes to rest it loses its hooks, and, increas- ing in size, develops into a small round bladder worm. The head of the future tapeworm is then de- veloped in an invagi- nation of the cyst wall, and the com- plete organism (fig. 68) thus formed is known as a cysticer- cws, or bladder worm. During its develop- ment the cyst pushes the tissues of the host aside to make room for itself and an outer cyst is formed around it, made up of connective tissue of the host. The total time consumed in the development of the cysticercus from the embryo is variously estimated from seven to eighteen weeks. Hertwig states that the larva has com- pleted its develop- ment in eighteen 74 INSPECTION OF MEATS FOR ANIMAL PARASITES. weeks, and gives the following table to determine the age 1 of the cysticercus : Age in weeks. Entire cyst. Cysticercus with- out connective tissue cyst. Scolex. Natural size. Stretched. 4 6 8 10 4.0 by 3.5mm 4.2 by 3.5 inm 4.5 by 3. 5 mm 5 by 3.75-4 mm 5.6 by 3.5-4 mm .. . 6 by 4.5 mm 6 by 4.5 mm 6.25-7 by 4.5 mm .. G. 5-8 by 4.5mm... 7 5-9 by 5, ft mm . . 2.25 by 2.25 mm... 3 by 2.5inm 3.25 by 2.75 mm .... .1.5 by 3.5mm 4 by 4 nun 0.5 by 0.5 mm 0.7 mm. long. 1.3 nun. long. 2.9 mm. long. 3.3 mm. long. 3.5 mm. long. 4 mm. long. 4.25 mm. long. 5 mm. long. 5.5-6.25 mm. long. 7 mm. long. 1.5 by 1 mm 1.75 by 1 mm 12 14 16 18 22 1.8 by 1 mm P by 4 mm 6 by 4.5 mm 7 bv 5 mm . . . 2 by 1.25mm 2.25 by 1.75 mm . . . 2.5 by 2 mm 28 - -- The calcareous bodies may appear when the bladder worm is four weeks old; the suckers are fully developed at the eighteenth week. Occasionally bladder worms are found measuring 10 to 12 mm., with a scolex 8 to 9 mm. ; these parasites are more than 28 weeks old. If the infested animal is not slaughtered and does not die the cysts will eventually die and degenerate. Thus, in one animal killed 224 days after being infected with tapeworm eggs, the cysts were calcified (Saint-Cyr). The parasites which inhabit the seats of predilection (see p. 78) seem to be the last to die. The degeneration may include (1) the surrounding connective tissue cap- sule, which becomes opaque and thick- ened, (2) the bladder cyst of the worm, which turns to a yellowish green, soft, cheesy mass, or (3) both. If, however, the animal is slaughtered before the cysticerci become calci- fied, and the meat used for food, the cyst around the hydatid is digested upon arriving in the stomach of 1 During the proofreading of this report an article by Ostertag (1897, pp. 1-4) has reached us, in which he adds some details of value in judging the age of the bladder worms. His chief results may be summarized as follows : (1) A steer may become infected with beef measles, and yet recover from the attack without showing upon post-mortem any calcined cysts. (2) C. boria, 18 days old, is spiudleform, and measures 4 mm. long by 2 mm. broad ; a differentiation into scolex and bladder is not yet present. (3) Up to 33 days after infection the parasite is surrounded by a cheesy mass, the result of exudation ; this afterward disap- pears. (4) At 25 days old the parasite shows the primordium of the scolex. with faint indication of the suckers. (5) When the parasite is 59 days old the suckers may be seen with the naked eye ; calcareous corpuscles are also present. (6) The lumen of the suckers is visible in parasites 73 days old. FIG. 70. Dorsal, apex, and lateral views of the head of Beef-measle Tapeworm (Taenia sa- ginata), showing a depression in the center of the apex. X17. (Original.) FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 75 man. The hydatid cyst is also digested, the head and neck alone remaining uninjured. The scolex then passes from the stomach into the small intestine, fastens itself to the wall by means of its suckers, and gives -rise to segments by transverse division (stabilization) directly back of the head and neck. New segments are formed between the head and the old segments, so that the last segment is always the oldest and the segment nearest the head always the youngest. Segments are formed so rapidly that the worm is full grown at the end of about three months. Perroucito estimates, that about 13 to 14 new segments are formed each day, which results in an average increase in the length of the V J worm at the rate of about 3 cm. per day for the first month Genital organs, segment, em completed to the The disease in cattle in the skel and 14 cm. per day for the second month, both male and female, are developed in every bryos are produced, and the life cycle is point from which we started out. BEEF MEASLES. cattle. Cysticercus bovls has been found in etal muscles, in the heart, the adipose tissue around the kidneys, the subperitoneal con- nective tissue, the lymphatic glands, and between the convolutions of the brain; cases are also reported of its presence in the lungs and liver. In some infections of cattle which have been made no symptoms of disease were noticed, but in others quite severe symptoms have been ob- served. About fifteen to twenty days after infec- tion the animals became FIG. 71. Segments from various strobilae of Beef-measle Tapeworm (Taenia saginata) showing forms of proglottids which are occasionally found: a, elongated segments; 6, beadlikc segments; c, a portion of strobila in which the seg- mentation is not distinct; d, monilif'orm segments (a and 6 original ; c and d after E. Blanchard, 1894). feverish, the sickness in- creasing to the twenty- fifth to sixtieth day, the patients becoming ema- ciated. Several cases proved fatal, while others recovered and were apparently none the worse for the experiment. These symptoms have been noticed only in cattle which have been experimented upon and which have received enormous infectious, and it is very generally supposed that an ordinary infection will have little or no effect upon the animals; we can, however, easily imagine that such an infection as Fleming describes, where he found 300 cysticerci in one pound of muscle, will injure the host. When the heart is heavily infected its action must be seriously impeded. As an example INSPECTION OF MEATS FOR ANIMAL PARASITES. of an extreme case we may take the following description of symptoms and post-mortem examination, taken from Ziirn (1882, p. 187) : Symptoms. Four days after feeding segments of T. saginata to a healthy three- months-old calf, the patient showed a higher temperature (the normal temperature was 39.2 C.) The calf ate but little on that day, showed an accelerated pulse, swollen belly, staring coat, and upon pressure on the sides showed signs of pain. The next day the animal was more lively, ate a little, and for nine days later did not show any special symptoms except pain on pressure of the abdominal walls, and a slight fever. Nine days after the infection the temperature was 40.7 C., pulse 86, respira- tion 22; the calf laid down most of the time, lost its appetite almost entirely, and groaned considerably. When driven it showed a stiff gait and evident pain in the Bide. The fever increased gradually and with it tile feebleness and low spirited- ness of the calf, which now retained a recumbent posi- tion most of the time, being scarcely able to rise without aid, and eating only mash with ground corn. Diarrhea common ced, the temperature fell gradually, and on the twecty - third day the animal died. The temper- ature had fallen to 38.2 C. During the last few days the calf was unable to rise; in fact, it could scarcely raise its head to lick the mash placed before it. Pulse was re- duced by 1C beats. On the last day the heart beats were FIG. 72. Sexually mature segment of Beef-measle Tapeworm (Taenia sagin- ata): ep, cirrus pouch, with cirrus; dc, dorsal canal; gp, genital pore; n, lateral longitudinal nerves; ot>, ovary; sg, shell .gland; t, testicles; ut, median uterine stem, enlarged (in part after Leuckart); v, vagina; ve, ventral canal, connected by transverse canal, tc; vd, vas. deferens ; vg, vitellogene gland. very much slower, yet firm, and could be plainly felt. Several days before death the breathing was labored and on the last day there was extreme dyspnoea. * Post-moriem. Body cavities contained reddish serous exudate. Subderrnal con- nective tissue was oedematous. Muscles were redder than usual, in some places very dark red. In the heart muscles were innumerable (many thousand) round tubercle-like bodies, 1.5 to 3 mm. long, 1.2 to 5 mm. wide, yellowish-white in color. Young cysticerci lay embedded in these smeary chalky cysts. Some of these cysti- cerci were round, but the majority were bottle-shaped and contained round cells and fat globules, and were inclosed by a membrane. The bottle-shaped cysticerci measured 0.557 mm. long while their greatest diameter was 0.326 mm. Cysts were also found in all the muscles, especially in the muscles of mastication, dorsal muscles of the neck, etc., and finally, though not many, in the diaphragm, and outer and inner diagonal abdominal muscles. Acute cestode tuberculosis is a name which is sometimes applied to designate a heavy infection with cysticerci. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 77 Failing to diagnose the presence of the parasites by symptoms exhibited by the cattle, we have recourse to other methods which have occasionally proved of use : (1) By examining the under side of the tongue it is occasionally pos- sible to find small lumps about the size of a pea or bean which can be moved slightly with the fingers, and which in many cases represent cysticerci. It is rare that this method leads to any practical results, and no confidence should be placed in it. (2) Several authors suggest cutting out a portion of muscle one of the neck muscles, for instance and examining it for the cysts. Although the diagnosis may sometimes be made by operating in this manner, we can hardly see how it can be of any practical value, since no treatment, except good nourishment, which cattle should always have, can at present be suggested for animals infested with these para- sites. Moreover, extirpation of a muscle should be practiced only by professionals, and a negative diag- nosis in this case is of no value. (3) The only positive diagnosis is post-mortem examination, and this, for the comfort of man, as will be shown, should be made on all slaughtered cattle. An examination of the internal and external muscles of the jaws, the tongue and neck, as well as the heart and muscles seen from the body cavity, will generally suffice to determine whether the cysti- cerci are present or not. Treatment. There is no medical treatment to be suggested. Prevention, however, is extremely sim- ple. We have seen (p. 72) 'that cattle obtain the eggs directly or indirectly from human excrements; hence persons who have this tapeworm should not void their excrements in fields or barns where they can contaminate the fodder or water used for cattle. "If this plan is followed, not only will the spread of the parasite among cattle be prevented, but also the spread of this species of tapeworm among man, since the latter, as has already been stated, becomes infected by eating meat containing the larval stage. It lies entirely within the power of the inhabitants in stock-raising districts to prevent the infection of their cattle with this parasite. FIG. 73. Gravid segment of Beef-measle Tape- worm (Taenia gagin- ata), showing lateral branches of the uterus, enlarged (original). ABATTOIR INSPECTION. 1 As beef measles, when swallowed by man, gives rise to an adult tapeworm, the question of using meat infested with this parasite and 1 Since this report was sent to press we have received a very extensive article upon abattoir inspection for beef measles, written by Rasmussen (1897), of Kopenhagen. Persons who wish to inform themselves upon this subject more in detail are referred to the articles by Rasrnussen (1897) and Friis (1897). 78 INSPECTION OF MEATS FOR ANIMAL PARASITES. the question of abattoir inspection naturally arise. Although this spe- cies of tapeworm does not contribute to the comfort of man, it can not be looked upon as a dangerous parasite. It may bring about digestive troubles, but will not per se result in the death of the patient; and with proper treatment it can be gotten rid of, although sometimes with difficulty. Nevertheless, its presence in man should, of course, be prevented when possible, and. this can be done by very simple means, namely, (1) by an inspection of cattle at the slaughterhouses to deter- mine the presence or absence of the larval stage, and (2) by submitting infested meat to processes which kill the parasites. (1) Position of the parasites. Inspectors should examine very thor- oughly the muscles of all cattle slaughtered, especially the inner and outer muscles of mastication and the heart; cuts should be made into the muscles of the jaws parallel to the bones. The following table, taken from Ostertag, giving the result of the meat inspection in Berlin for 1889-90, is exceedingly instructive, as it shows the general distribution of the parasites in the various muscles : Cases. (1) In muscles of the jaws 316 (2) In muscles of the jaws and in the heart 39 1 (3) In muscles of the jaws and in the tongue. . .; 4 (4) In muscles of the jaws and in the neck 1 (5) la muscles of the neck I (6) In muscles of the neck and in the tongue 1 (7) In muscles of the tongue 2 (8) In muscles of the tongne and heart 2 (9) In muscles of the tongue and muscles of breast 1 (10) General infection ^ 22 Thus it is seen that in these examinations the muscles of the jaws were infested 360 times, while the other organs were infested but 55 times (in this computation the 22 cases of general infection are omitted) ; in other words, in about seven-eighths of all cases found parasites were present in the muscles of the jaws. Occasionally, in very heavy infections, the parasites occur also in the lymphatic glands, the lungs, the liver, the brain, etc. The recognition of the fully developed bladder worms is an easy mat- ter for anyone who understands the structure of the parasite ; although their detection in superficial layers is rendered somewhat difficult in case the surface of the meat becomes dried. In case of doubt the sus- pected cysticercus may be placed between two fingers and a gradual pressure exerted upon the cyst. This will cause the protrusion of the head, upon which the four suckers can be easily distinguished. A sim- ple microscopic preparation of the parasite, made by pressing it between two pieces of glass, will reveal the presence of the calcareous corpus- cles of the parenchyma. Differential diagnosis. The only parasites in cattle which would be likely to be mistaken for beef measles are Cysticercus tenuicollis (see FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 79 p. 96) and Echinococcus polymorplius. The absence of hooks, however, immediately distinguishes the Beef-measle Bladder Worm (Cysticercus boris] from C. tenuicollis, which occurs in the serous membranes, etc., but not in the muscles. Young stages of the echinococcus hydatid, which are occasionally found in the muscles, differ from the Beef-measle Bladder Worm in several characters, which render a differential diag- nosis comparatively easy, as seen from the following table: Oysticercus bovig. Echinococcus, p. 113. One unarmed liead present.. Head absentfpr numerous armed heads present in brood capsules (p. 116). Cuticle thin ' Cuticle thici and laminated (p. 116). Form oval Form round. A positive diagnosis of the younger stages of C. bovis (i. e., before the head has developed), or of degenerated specimens, is sometimes more difficult; the younger stages and the totally degenerated specimens will not develop further if eaten; the specimens which are only partially degenerated may, however, still retain enough vitality to develop into adult tapeworms. The oval or pyriform body gives a probable diag- nosis for the younger stages, while the presence of calcareous corpuscles (seen only with the microscope) furnishes a method of diagnosis for the degenerated forms. Even in completely degenerated cysts the calca- reous bodies may be discovered ; these should, however, not be mistaken for fat globules which are more strongly refractive, possess a broader and darker edge, and do not change on addition of acetic acid. It is more difficult to distinguish the calcareous corpuscles from certain crys- tals of calcium carbonate; the latter lie in clumps and overlap each other, and upon being treated with mineral acids (as weak hydrochloric acid) completely disappear, while when the calcareous corpuscles are treated with acids their organic base retains the original form. Rissling gives the following method for determining the presence of cystic^rci in chopped meat and sausage, but its application does not seem very practicable, for this country at least. It appears to us much better to inspect meat for measles before it is cut up. Prepare 1 to 4 liters of a solution of caustic soda or caustic potash having a specific gravity of 1.15; place this, together with the teased or chopped meat, in a funnel- shaped dish, stir well aud allow to stand. The worms will then sink to the bottom while the rest of the material will float. Schmidt-Miilheim's method consists in artificially digesting the meat at 40 C. After several hours the bladder portion of the cysticerci will be more or less destroyed, but the heads will not be affected ; they sink to the bottom of the vessel and may be recognized us small white bodies. In armed cysticerci (C. celluloaae, p. 89, etc.) the hooks will be found. 80 INSPECTION OP MEATS FOK ANIMAL PARASITES. Frequency o/Cysticercus bo vis in cattle. Xo exact statistics have been published for this country. The proportions of infected cattle slaugh- tered in Prussia for 1892 were as follows: Kegierungsbezirk. Propor- tion. Regierungsbezirk. Propor- tion. Stralsund 1:51 Kassel 1 1 653 Oppehi 1:229 Bronaberg. . Hannover Breslau Liineburg j 1:350 1 : 2, 500 Danzig 1:426 Koblenz 1-610 Stettin ^ Marien werder Poseii 1 1:3, 500 Frankfurt . . 1:775 1 6 659 Merseburg Liegnitz 1 20 000 1:915 1 25 586 1 34 182 | 1 : 1, 025 The average proportion for the first 20 Regierungsbezirke mentioned was 1:1,631. These statistics appear rather low when we notice the following figures for the Berlin abattoir: Tear. Cattle slaugh- tered. Cattle infected. Proportion. 188388 2 1888 89 141, 814 113 1 1 ''55 1889 9C 154, 218 390 1-395 189091 124, 593 263 1 -474 1891-92 136, 368 254 1-541 1892 93 : 142, 874 214 1-672 This apparent increase in proportion from 1:1,255 in 1888-89 to 1:672 in 1892-93 is due to the more thorough inspection following Hertwig's discovery of the seats of predilection of the parasite, rather than an actual increase in the number of animals infected. Influence of age and sex of the host. According to certain European statistics about 50 per cent of the cases of infection are found in ani- mals 2 years old ; about 20 per cent of the cases in animals 3 years old, and about 4.5 per cent in animals of 1, 4, 5, 6, 7, and 8 years old, respec- tively. Beef measles are also said to be more common in male aniiikals than in female animals. Influence of season. According to Easmussen, bladder worms are more common in late summer and early fall than at other times of the year. From statistics he gives for Copenhagen it appears that for the years 1890-96, the total number of cases found and their proportion to the entire number of animals slaughtered were as follows : Mouths. Cases. Per cent. Months. Cases. Per cent. 39 17 13 0.10 38 19 52 .31 43 20 69 .32 April 20 .10 81 .35 Mav... 24 .12 54 .21 13 09 38 .18 FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 81 Disposition of measly beef. Measly beef should be condemned to the tank as unfit for food when the infection is general, or when the inva sion by the parasites has caused a watery and "flabby" condition of the meat. In case of light infection the meat can be used for food after the cysticerci have been rendered harmless, but even in these cases it is well to cut away the most heavily infested portions. Cases of so-called "single infection" should be treated the same as cases of light infection, for although it may unquestionably happen that an animal is infected with but one bladder worm, still the finding of only one parasite is no proof that other parasites are not present; further- more, in a number of cases of alleged " single infection," later and more thorough examination has revealed further worms. In case of infection with only very young parasites, in which the suckers are not fully developed, the meat may safely be passed and allowed to go on the market without restriction. In case of infection with fully developed live bladder worms, the meat should be subjected to some safeguarding method before being placed on the block, or it should be sold under declaration of its exact character. Opinion differs as to the method which should be followed in case of infection with degenerated bladder worms. It is maintained by some that this meat should be allowed on the market Without restrictions. FIG. 74.-Egg of Beef -measle Tapeworm (Taenia The finding Of degenerated CystS, saginata), with thick eggshell (embryophore), or bladders, however, is no proof that all the parasites are dead, for not only are cases more or less frequently found in which both live and degenerated bladders are present, but even if the cyst, or bladder, is degenerated the head may, in some cases, still retain its vitality. It is accordingly safer to treat carcasses with degenerated cysts in the same manner as carcasses with live cysts; and should any exception to this be made, such exception should be limited to cases in which the degenerated parasites are found in the muscles of the jaws. The cysticerci may be killed by cooking, by salting or corning, or by cold storage. Cooking. This is the surest method of killing the parasites, but it is open to the serious practical objection that, according to estimates, cooking in a steam sterilizing apparatus results in a shrinkage of from 33 to 50 per cent, and this heavy loss will undoubtedly be a drawback to its general use. Perroncito found that below 30 C. the movements of the worms are very slight, or practically nil; from 36 to 38 C. the movements are livelier; at higher temperature they diminish, ceasing at 44 C.; they 5257 No. 19 6 82 INSPECTION OP MEATS FOR ANIMAL PARASITES. "die sometimes at 44 C., now and then at 45 C., and always at 46 C." He " therefore concluded that they could in no case survive 47 C. and 48 C. [=116.6 to 118.4 F.] when they are maintained at this temperature for at least five minutes. Lewis found a somewhat higher temperature necessary in order to kill the worms. He states (1) That exposure to a temperature of 120 F. for five minutes will not destroy life in cysticerci, but they may continue to manifest indications of life for at least two or three days after such exposure; (2) that exposure to a temperature of 125 F. for five minutes does not kill them, but (3) after being subjected to a temperature of 130 F. for five minutes they may be considered to have perished. After exposure to this and higher temperatures, in no instance have I been able to satisfy myself that the slightest movements took place in their substance when examined even under a high power. At least, it may be confidently asserted that after exposure for five minutes to a temperature of 135 to 140 F. life in these parasites may be considered extinct. Pillizzari found that cysticerci died at a temperature of 60 C. ( = 140 F.), while according to Hertwig 52 C. ( = 125.6 F.) reduces the bladder worm to a smeary, soft condition, so that it can be easily flattened out between two pieces of glass. It is important to recall, however, that in cooking large pieces of meat the temperature of the inner portion does not rise as rapidly as that of the outer portion As an index to the duration of cooking required in order to guaranty that all the bladder worms are killed, Ostertag gives the rule of two hours' cooking for pieces of varying length, but not over 12 cm. (=6 inches) thick. Probably the best criterion in forming a judgment is the color of the meat; 60 to 70 C. (=140 to 158 F.) causes a reduction of the haemoglobin, and this results in giving a gray color to beef and a white color to pork; when slices of cooked beef (or pork) assume this gray (or white) color, it can safely be assumed that all the cysticerci have been killed. In 1894 and 1895 Berlin, Prussia, cooked 342 insured beef-measly carcasses, representing insurance policies to the value of 57,223.30 marks (about $13,619.15). During the same period there were con- demned 221 uninsured beef-measly carcasses, valued, on the same basis, at 36,977.60 marks (about $8,800.67). The raw beef was sold to the parties having the cooking in charge at 20 pfennige (about 5 cents) per pound, and after being cooked was sold to the public at 30 to 35 pfennige (about 7 to 8f cents) per pound. Cooked measly pork was sold at 40 pfennige (about 10 cents) per pound. ; . Salting. Salt solution kills the bladder worms in twenty-four hours, the parasites becoming shriveled. Here, again, it must be remem- bered that it takes some time for the salt to reach the deeper layers. It is probable that this method will to some extent supersede the cooking, since the shrinkage by salting is estimated at only 6.6 per cent. Two carcasses of 500 pounds each, treated at Kiel by different methods, form an excellent comparison. The cooked carcass gave 300 pounds of beef which sold at 30 pfeunige (about 7i cents per pound : in FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 83 all, 00 marks (about $21 .42) ; the salted carcass gave 400 pounds of beef which sold at 40 pfeunige (about 10 cents) per pound; in all, 184 marks (about $43.79). In Saxony measly beef has sold as high as 1 mark (about 24 cents) per pound, while in some parts of Germany it has been sold from 2 to 10 cents per pound. In a few instances the prejudice against this meat was so great that it could not be sold at all. In general, however, the salted measly beef is easier to dispose of than the cooked measly beef. Ostertag gives as rule for salting the following: Cut the meat into strips of any given length, but not over 6 cm. (3 inches) in thickness, and place for two weeks in a brine composed of 1,000 parts of water, 250 parts of salt, 20 parts of sugar, and 2 parts of saltpeter. As a practical test to determine whether the salting is thorough, and the parasites are dead, he suggests the use of a 1 per cent solution of nitrate of silver. If applied to the surface of lightly cured meat this solution will produce no change in the appearance; if the meat is fully cured, a momentary milky opacity will result, owing to the formation of chloride of silver. To use the test, wash the meat thoroughly in water, then wipe it with a cloth, and make a quick incision through the middle of the piece to be tested; apply a few drops of the nitrate of silver to the cut surface. Cold storage. Perroncito maintains that Cysticercus bovis dies four- teen days after its host has been slaughtered. More recent investiga- tions by Ostertag, Zschokke, Glage, and others have shown that two weeks form too short a limit, but that none of the worms can survive three weeks; beef-measly meat which has been in cold storage for three weeks may therefore be looked upon as harmless. In view of these recent investigations, I can see no reason why light cases of beef measles (but not pork measles, see p. 94), which have remained three weeks in cold storage, should not be passed as first-class meat and allowed on the open market without further restrictions. ' During certain seasons of the year, however, there is a practical objec- tion to this method of safeguarding which has been thus far overlooked (except by Friis). Experience has shown that meat which has been in j cold storage for this length of time during summer will spoil much more ' rapidly when taken out of the cooler than meat which has been placed i in the ice box only long enough to cool and "firm." i THE ADULT TAPEWORM IN MAN AND METHODS OF PREVENTING THE INFECTION OF CATTLE. Taenia saginata, or the large Unarmed Tapeworm, is the most com- mon of the ten species of tapeworms found in the intestine of man. \A form with which it has frequently been confounded is a tapeworm I (T. solium) of about half the size (2 to 3.5 m.), acquired by eating pork i infected with larvae ( Cysticercus cellulosae], which are very similar to i those found in the cattle, but are somewhat larger and possess a double crown of hooks on the head. 84 INSPECTION OF MEATS FOR ANIMAL PARASITES. The Unarmed Tapeworm of mail is almost cosmopolitau, and is especially common in Africa and Asia. Many of the puhlished statistics of the relative frequency of T. saginaia and T. solium are, however, to be taken with reserve. In some countries the Beef-measle Tapeworm is said to be increasing and the Pork-measle worm to be decreasing in frequency; but in some cases these statements are unquestionably based uponmisdeterminations. Physicians too frequently make their determinations upon the external form of the segments a method which can not be relied upon, even when such detemination is made by a specialist. In America, for instance, it is fre- quently stated that T. soUum is more common than T. saginaia, but this view has been shown to be erroneous (Stiles, 1895, p. 281). According to the official medical sta- tistics of the late civil war, 566 cases of tapeworms were noticed in 5,548,854 patients from July 1, 1862, to June 30, 1866, or 1 : 9,803, but no indication as to the species found is given. In some countries statistics seem to show that tapeworm disease has been on the increase. Thus JbS6renger-Fe'raud ( 1892) records the following statistics for the maritime hospitals of France : Tear. Cases. Patients. Cases per 1,000 patients. 1861-65 33 130 927 0.20 1866 70 95 152, 822 62 187175 422 137, 361 3.06 1876-80 1, 108 130,898 8.45 1881 85 1 , 565 155. 646 10 05 1886 90 2, 253 152, 852 14.80 Be'renger-Fe'raud looks upon 1860 as the date of introduction of T. saginaia into France, but Blanchard has shown that this is not the case, although he admits that it has increased in frequency from year to year. Krabbe has published the following valuable statistics regarding tapeworms of man in Denmark: Tear. T. iaginata. T. solium. Dipylidium caninum. Bothriocepha- lu latus. Before 1869 37 53 1 9 1869-80 67 19 4 11 1880 87 87 5 4 5 1887 95 89 6 30 ' It seems quite well established that there has been an increase in the frequency o T. saginata in man in some districts, but since Hertwig's important observation in 1889-90 regarding the seats of predilection of the larval stage the destruction of so many more larvae must necessarily have resulted in decreasing the frequency of this species in man. There can be no question that since the trichina scare in 1860 and the following years, which led to an inspection of pork in some countries, and to greater care in cooking it in others, T. solium has decreased in frequency. The following key will aid in the determination of the tapeworms of man: KEY TO THE ADL T- LT TAPEWORMS OF MAN. [For forms recorded in this country follow Roman type.] (1) Head with two elongate grooves or slit-like suckers ; rostellum absent; uterus with special pore; genital pores generally dorsal or ventral. Bothriocephalldae, 2. Head with four cup-shaped suckers; rostelltiin present but not always evident; uterus without special pore ; genital pores generally marginal... Taeniidae, 4. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 85 BOTHRIOCEPHALIDAE (Subfamily Bothriocephalinae). (2) Body with external segmentation ; head with two elongate or groove-like suckers : Genital organs single in each segment; cirrus, vulva, and uterus open ventro- median Bothriocephalus, 3. Genital organs double in each segment ; cirrus, rnlva, and uterus open ventrally ; worm very large, attains about 10 meters -in length by 2 cm. in breadth; life history unknown. Found in Japan Krabbea grandia. BOTHRIOCEPHALUS. (3) Very large, attains 10 meters or more in length, reddish gray in color; very rare in this country ; obtained from eating fish: Common pike (Lucius lucius), ling (Lota lota), perch (Perca fluviatilis) ; several members of the salmon family (Salmo urnbla, S. trutta, S. lacustris, Thymallus vulgaris, Coregonus lavaretus, C. albula, Onchorrhynchus Perryi, and perhaps Salmo salar) B. latus. (B. latus includes B. cristatus Davaine, 1874.} Length a little less than four feet; found in Greenland B. cordatus. (A larcal Bothriocephalus (B. Mansoni) is found in subperitoneal connective tissue of man . ) TAKNIIDAE. (4) Egg with thin outer shell and thick brown inner shell (embryophore) ; uterus median and longitudinal with lateral branches; head generally armed; larval stage a Cysticercus, Coenurns or an Echinococcus generally in herbivora; adults in carnivorous or omnivorous animals Taeniinae, 5. Egg with thin transparent shells, and frequently in egg capsules; in some cases scattered through the segment; head nearly always armed with booklets on rostellum; larval stage a cysticercoid; adults in birds and mammals. Dipylidiinae, 1. TAENIINAE. (5) Head with armed rostellum 6. Head unarmed, rostellum absent; strobila attains 3 to 10 meters in length; ovary of pore side undivided; uterus with 17 to 30 branches on each side; the most common tapeworm of man in this country ; larva in cattle. Taenia saginata, p. 71. (6) Rostellum with two rows of hooks, 24 to 32 in number; strobila attains 4 to 8. meters in length; ovary of pore side divided; uterus with 7 to 12 branches each side; comparatively rare in this country; larva in swine. T. solium, p. 89. Rostellum (?) J ; strobila attains 5 meters in length; terminal proglottids 27 to 35 mm. long by 3.5 to 5 mm. wide T. confusa. (The larval stages of T. solium and T. echinococcus are also found in man.) 1 Ward describes the rostellum as having 6 or 7 rows of very small hooks. Through the kindness of Professor Ward, I have recently examined the head and a number of segments of the original material. This examination leads me to look upon the head as a head of Dipylidium caninum, which has accidentally been placed in the wrong bottle, a possibility which had also occurred to Ward. Regarding the remarkable segments, I do not wish to commit myself until I have opportunity to study a complete specimen. 86 INSPECTION OF MEATS FOR ANIMAL PARASITES. 1>IPYLII)IINAE. (7) Suckers unarmed 8. Suckers armed (the suckers of the young specimens will undoubtedly be found to be armed, although the specimens thus far found in man were unarmed, the hooks prob- ably having fallen), the hooks being arranged in circular roivs on border; hooks on rostellum resemble a hammer in form, about 90 in number and arranged in a double row, or rostellum rudimentary and unarmed; strobila 25 to SO cm. long. Very rare; not yet recorded for America. Larra probabl'/ in some invertebrate. JJaraiuea madagascuriensis. (8) Genital pores double; two submedian ovaries in each segment; several rows of hooks on rostellum; strobila attains 15 to 35 crn.jn length; gravid segments elliptical. Adults found in dogs and cats; rare in man. Larva found in lice and fleas of dogs ( Trichodectes cams and Pulex serraticeps) . . Dipylidium caninum. Genital pores single and unilateral (on left of segment) ; rostellnm with 21 to 30 hooks, the dorsal root longer than prong or ventral root ; three testicles nor- mally present in each segment; eggs with three envelopes Hymenolcpis, 9. (9) Hooks (24 to 28 in number, 15 /* long) present on rostelliim; body 10 to 15 mm. long; not uncommon in Italy ; found also in other parts of Europe. Found m rodents (rats, etc.), as well as man; larva develops in the villi of the intes- tine H. marina. (Including Taenia naiia.) Rostellum rudimentary and unarmed; 20 to 40 cm. or more long; adult generally parasitic in rodents (rats); larval stage develops in certain insects (Asopia farinalis, Anisolabis annnlipes, Akis spinosa, Scaurus striatus) H. diminiita. (Including Taenia Jtaropunctata.) If a person is known to have a tapeworm, it is of great importance, both from an economic (agricultural) and a hygienic standpoint, to know whether one of these two tapeworms (T. saginata, the Beef-ineasle Tapeworm, and T. solium, the Pork-measle Tapeworm) is present, and if so, which one. This can be determined in several ways: (1) Since the Pork-measle Tapeworm comes from pork, it will not be found in persons who abstain from eating that meat, as is usually the case among Hebrews. So that if one of these two parasites were found in such persons it could be only the Unarmed Tapeworm. (2) On the other hand, those who eat pork but no beef would not be infested with the Unarmed Tapeworm, but we would expect to find in them the Pork-measle (armed) Tapeworm. These two modes of diagnosis do not hold in all cases, for, as already stated, man is subject to ten different species of tapeworms. Most of the remaining eight species are, however, so totally different from the two under consideration that a positive diagnosis can be made by com- paring the worms with figs. 73 and 81, and with the key given above. (3) When segments of the parasite break off and wander out of their own accord or with stools of the person affected, it should be noticed whether several segments are joined together or whether every portion consists of a single segment. In the former case, the parasite is gen- erally the armed parasite, in the latter case generally the unarmed parasite. (4) Take a segment of the parasite found in the stool or bed, press it between two pieces of glass and hold it up to the light. Comparing FLUKES AND TAPEWOEMS OF CATTLE, SHEEP, AND SWINE. 87 it with figs. 73 and 81, notice whether the uterus has 17 to 30 'branches on each side of the main trunk (Unarmed Tapeworm) or from 7 to 10 branches each side (Armed Tapeworm). (5) In case the head is found, notice whether hooks are absent (unarmed) or whether two rows of hooks are present (armed). The necessity of knowing which parasite is present is, first, that the Armed Tapeworm injures man, not only because it inhabits his intes- tine, but also because the larval stage may develop in the muscles, eye, and other portions of the body, and a man who has the Armed Tapeworm stands in constant danger of infecting himself with these larvae. The .Unarmed Tapeworm, on the other hand, develops only in the intestine, its larval form being unable to develop in man. In the second place, it is important to know which tapeworm is pres- ent in a person, especially in a farm hand, for if he has the unarmed form there is constant danger of his infecting the cattle by passing his excrements in fields where cattle feed; if he carries the Armed Tape- worm he will infect the hogs, should he void his excrements in a place to which swine have access. Symptoms. The symptoms exhibited by a patient troubled with tape- worms are both general and local: Itching at the extremities of the intestinal canal, and various dyspeptic symptoms; uncomfortable sen- sations in the abdomen, 1 uneasiness, fullness or emptiness, sensation of movement attributed to the movements of the parasite, colicky pains; disordered appetite, at times deficient, at other times craving; paleness and discoloration around the eyes; fetid breath; sometimes emaciation; dull headache; buzzing in the ears; twitching of the face; dizziness; often the uncomfortable feelings in the intestine are increased by fast- ing and relieved after a hearty meal; fainting, chorea, epileptic fits. Diagnosis. A positive diagnosis can be made by finding the segments of tapeworms in the stools, bed, or clothes of the patient, or by a micro- scopic examination of the faeces in search of eggs. Treatment. It is always advisable to consult a physician in regard to treatment, especially when the patient is much run down in health or naturally delicate in constitution, since "in weak persons, such as those having consumption, the treatment, if admissible at all, must be conducted with the greatest care, lest the patient's strength be exhausted" (Pepper). It is not always possible, however, for men on the ranches to obtain the services of a physician, so the following hints are given in regard to treatment and may be followed without danger by a strong and healthy person of ordinary intelligence: Before taking any of the medicines suggested below, it is necessary to prepare for the treatment by removing all obstructions in the intes- tine to the free exit of the parasite. This can best be done by living 'The most constant symptom which I observed in an experimental infection of myself with T. sayinata was the sensation which one experiences in the rapid descent of an elevator. This peculiar feeling frequently occurred, especially when walking. 88 INSPECTION OF MEATS FOR ANIMAL PARASITES. for two or three days on a light diet of milk, coffee, soup, and bread; but vegetables should not be taken. On the evening before taking the medicine it is also advisable to give the patient a thorough injection of 1 to 2 quarts of warm water, to which 1 to 2 tablespoonfuls of pure glycerin may be added. Early the next morning one of the following doses may be taken: (1) Take 1 to 2 ounces of oil of turpentine -f- 1 ounce of castor oil, mixed with the white of an egg and some sugar. Take the \vhole dose at one time, and if a move- ment of the bowels does not follow within two or three hours, take another dose of castor oil (1 ounce) (Leidy, 1885). Objection has been raised by some practitioners to the use of oil of turpentine on the ground that it causes an intense burning sensation in the intestine and pro- duces headaches which may last several days. (2) The most generally useful remedy is the oleo-resin of male fern, l which is in reality an ethereal extract of the drug. A half drachm or drachm of the remedy is given in tjie morning after two days' restriction of diet, and in the evening a brisk cathartic, such as castor oil, should be administered. Sometimes calomel is given in combination with the oleo-resin. The patient should remain abed after the admin- istration of the remedy, to avoid syncope and other effects of large doses of the drug (Pepper, 1894). In overdose, this medicine is a distinct poison; six drachms have caused death. (3) One or two ounces of pumpkin seeds ground and made into a paste with sugar. Follow in an hour with a dose of castor oil. This is one of the best, cheapest, and safest tapeworm remedies. (4) Tanret's Pelletierine is very highly recommended but is rather expensive ($2.50 per dose) and often difficult to procure fresh in this country. In case this is taken the instructions which come with the bottle (one dose) must be strictly carried out. Many other remedies could be suggested, but those given above are among the most simple and will suffice for this report. Whatever anthelmintic is used, the medicine should be procured as fresh as possible. Many failures in treating for parasites are due to the fact that the remedy used has lost its anthelmintic property. When the parasite is being passed the patient should evacuate into a vessel containing warm water, the object of this being to prevent the worm from breaking or attempting to retain its hold in the intestine in case it is still alive, a.s it will frequently do if it comes in contact with any cold object. The patient should likewise avoid pulling the worm while it is being expelled, for he is thus liable to break it. When the movement is completed the stool should be examined thor- oughly for the head, for if this has remained in the intestine it will give rise to new segments again, and in about three or four months the patient will discover that he is still infected. If the head is not found upon examination of the stool, it is best not to repeat the treatment until the segments have again appeared, for, as the head is quite small, it may have escaped notice, although present in the stool, and in that case the second treatment would be useless. Prevention. After what has been said, it is exceedingly easy to see 'Male fern and kamala capsules are put up ready for use. Directions come with each box. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 89 the measures which should be adopted to prevent this disease: (1) Per- sons should not eat meat in which fresh cysticerci are present; (2) meat in which only a few cysts have been found, but have been cut out, should be thoroughly cooked or salted before eating, or, (3) such beef should lie in cold storage for three weeks at least; (4) cattle and hogs should not have access to human excrements, especially when it is known that persons in the neighborhood have tapeworms; (5) persons should not void their excrements on fields where live stock is feeding. By following out these simple instructions it will not be a difficult task to totally eradicate the tapeworm disease caused by T. saginata and T. solium in man, and the corresponding disease of "measles" caused by the larvae of these worms in cattle and hogs. In fact, it has been noticed in several parts of Europe, where meat is inspected, that certain tapeworms are gradually becoming rarer, owing to the condemnation of meat containing the cysts. 20. Pork Measles (Cysticercus cellulosae) of Man and Swine, and its adult stage, The Armed, or Pork Measle, Tapeworm (Taenia solium) of Man. [Figs. 75-83.] Many authors state that the Pork-measle Tapeworm is the common tapeworm of man for the United States, but a careful study of the sub- ject has shown this view to be erroneous. LARVA (Cysticercus cellulosae). For anatomical characters, compare figs. 75 and 76 with key, p. 21. .SYNONYMY. Finna Werner, 1786 ; Taenia hydatigera Fischer, 1788 ; T. cellulosae Gme- liu, 1790; T. finna Gmelin, 1790; Yesicaria hygroma humana Schrank, (-?-); V. finna suilla Schrank, (-?-) ; V. lobala suilla Fabricius, (-?-) ; Hydatis finna (Werner) Blu- menbach, (-?-); H. humana Blumenbach, (-?-); Taenia muscularis Jordens, 1802 ; T. hydatigena anomala Steinbuch, (1802); Cysticerciis finna (Gmeliu) Zeder, 1803; C. cellulosae (Gmelin) Rudolphi, 1808; C.finnus (Gmelin) Laennec, 1812; C. solium Koe- berle", 1861; C. suis Cobbold, 1869; Neotaenia Sodero, (1886) ; C.cellulosus of several authors; " Cysticerkus" cellulosae of Schneideiniihl, 1896. ANOMALIES. The names proposed by various authors for these supposed distinct species found in man, especially in the cranial cavity, are more or less descriptive. Hydatis piriformis Fischer, 1789 (=Taenia pyriformis (Fischer) Treutler, 1793 Cfys/icer- cus pyriformis (Treutler) Zeder, 1803 = C. Fischerianus Laennec, 1812) ; Taenia albopunctaia Treutler, 1793 (= C. albopunctatus (Treutler) Zeder, 1803= "T. albo- punctata hominis Treutler" of Cobbold, 1864); Cysticercus dicystus Laennec, 1812; C. acanthotrias Weinland, 1858; C. turbinatus Koeberle, 1861; C. meZawocepTiafasKoeberle", 1861; C. racemosus Heller, 1875 (C. bothryoides Heller, 1875 [nee Eeinitz, 1885] = C. multilocularis Kuchenmeister, (-?-) ; Trachelocampylus Davaine, 1880 (for Trach- elocampules Fredault, 1847). HOSTS. Man, swine, wild boar, and other animals. (See pp. 137-143.) ADULT (Taenia solium Linnaeus, 1758). For anatomical characters, compare figs. 77-81 with key, p. 84. SYNONYMY. Taenia solium Linnaeus, 1758 (after elimination of T. saginata and T. marginata) ; T. cucurbitina Pallas, 1766 (= T. solium Linnaeus, renamed) ; T. cucur- bitina Art [=var.] pellucida Goeze, 1782; T. cucurbitina, plana, pellucida Goeze, 90 INSPECTION OF MEATS FOR ANIMAL PARASITES. 1782; T. solitaria Leske, (1785), pro parte; Hal y sis solium (Linnaeus) Zeder, 1803; Taenia humana armata Rudolphi, 1810, pro parte ( Brera's, 1802, Tenia armaia umana) ; T. solium Linnaeus of Kiichenineister, 1852; T. hamolociilata Kiichenmeister, 1855 (possibly earlier; ; T. titrbinata Koeberl6, 1861 ; T. (Cystotaenia) solium of Leuck- art, 1863; T. tenella Cobbold, 1874 [nee Pallas, 1781]; (?) T. solium var. minor Guzzardi Asiuendo, 1876; T. officinalis Bos, 1894. ANOMALIES. (?) " Taenia Bulgaria" Werner, 1782 [uec Lin- naens, 1758] = T. dentata Batsch, 1786 ; ( ?) T. fenestrata Chiaje, 1833; T. (Cysticercus^acanthotriasof Leuckart, 1863; (?) T. fen- estrata Colin, 1885; T. solium fenestrata Colin, 1876; (?) T. fiisa, T. continua, T. solium fusa sen continua Colin, 1876; (?) T. scalariforme Notta, 1885 (= T. fenestrata Colin, re- named) = T. solium scalariforme Notta, 1885. PRE-LINNAEAN NAME. ( ? ) Taenia degener Spigelius, 1618. BIBLIOGRAPHY. For bibliography, see Huber, 1892. For technical discussion, see Leuckart (1880, pp. 617-713) ; R. Blanchard (1886, pp. 382-418). HOST. Man. It is an error for the Minnesota State board and the North Carolina Station to record it in dogs. FIG. 75. A piece of pork heavily infested with pork measles (Cysticer- cus cellulosae), natural size (original). Life history. The life cycle of the Pork Bladder Worm is exactly the same as that of the Beef Bladder Worm (see p. 72), except that the hog is the intermediate host. The following observations regarding the larval parasite at different ages have been made by various authors: Nine days after infection. An oval vesicle 33 fJ. kong by 24 // broad; connective tissue cyst absent. (Mosler.) Twenty days after infection. Parasite consists of a delicate, transparent bladder worm about as large as the head of a pin. The anlage (primordium) of the head is represented by a small, indistinct point ; surrounding cyst absent. (Gerlach.) Twenty-one days after infec- tion. Spherical, 0.8 mm. in diameter; slightly attenuate toward the point, showing the aiilage (primordium) of the head. (Leuckart.) TMrty-two days after infec- tion. Ellipsoid, 1 mm. to 6 mm. long by 0.7 turn, to 2.5 mm. broad. The largest specimens show the excretory system; the anlage (primor- dium) of the head equatorial ; connective tissue cyst very thin. Forty days after infection. Surrounding cyst still very delicate; about as large as a mustard seed, or somewhat larger; head very evident, suckers and hooks visible, but not complete. (Gerlach.) Sixty days after infection. Size of a pea or slightly larger. When freed from the connective tissue, cyst somewhat renal in form ; head as a small, white knob, but without neck; hooks and suckers fully developed. (Gerlach.) FIG: 76.- An isolated Pork-measle Bladder "\Vorm (Cyslicercus cellulosae), with extended head, greatly enlarged (original). FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 91 One hundred and ten days after infection. Neck developed; transverse lines slightly visible; bead is invaginated in tbe bladder. (Gerlacb.) Tbe determination of the age of tbe parasite is of importance in case that there is a guaran- ty of freedom from infection. According to Rasmussen the periods of guaranty are: In Prussia, Bavaria, and Austria, 8 days; in certain other parts of Europe, 9, 15, and 21 days; in Baden and Wiirteuiburg, 28 days, and in Saxony, 30 days. It is generally estimated that three to four months are re- quired for the parasite to com- plete its development, but as the hooks and suckers are formed after two and a half mouths it is not impossible that a parasite ten to eleven weeks old would develop into the adult tapeworm if eaten by man ; although, according to Gerlacb, pork measles less than two months old are not dan- gerous. The longevity of the bladder worm varies with cir- cumstances, but the factors here concerned are not understood. According to Railliet, cases have been observed in man where the bladder worm has caused severe cerebral troubles for twelve to fifteen years, and it has been observed in the eye for twenty years. Tbe worms may undergo calcareous degenera- tion very early, but as a rule this does not take place until tbe cyst is quite old. Tbe degeneration begins with the capsule and ends with tbe scolex, and, according to Morot, may be divided into four Stages, FIG. 77 Several portions of an adult Pork-measle Tape follows worm (Taenia soliiim), natural size (original). First stage. The capsule shows cheesy, opaque spots, but tbe fluid is clear, and the scolex is intact. 92 INSPECTION OF MEATS FOR ANIMAL PARASITES. FIG. 78. Large (a) and small (b) hooks of Pork-measly Tapeworm (Taenia golium), X280. (After Leuckart, 1880, p. 661, fig. 293.) Second stayc. Both the connective tissue capsule and the bladder cyst become cheesy; hooka are present, but the suckers more or less degen- erated. Third stage. Hooks are pres- ent, but not in definite order or number. Fourth stage. No traces of the hooks can be found in the para- site, which is reduced to a cheesy mass. Ostertag states that degeneration may take place before the hooks have formed. Ostertag has also shown that the hooks become loose, upon expres- sion of the scolex, only in dead bladder worms. PORK MEASLES. The disease in hoy*. The symp- toms in hogs are very indefinite, but a diagnosis may sometimes be made by examining the visible mucous membranes of the mouth, particularly under the tongue. See also the same subject for cattle, p. 77. A heavy infection of measles is more common in hogs than in cat- FIG. 79. Mature sexual segments of Pork-measle Tapeworm (Taenia solium), showing the di- gp, 'genital pore; n, nerve; ov, ovary; t, testi- cles ; to, transverse canal ; ut, uterus ; v, vagina ; vc, ventral canal ; vd, vas deferens ; vg, vitello- gene gland. XlO. (After Leuckart, 1880, p. 665, fig. 294.) vided ovary on the pore side: cp, cirrus pouch ; tie a fact easily Understood when we recall the feeding habits of the two animals, the comparative size of ^gjj. bodies, and of their stomachs. From 1884 to 1887, of 5,610 measly hogs found at the Berlin (Prussia) abattoir, 2,167 were heavily in- fested, 1,641 had medium infections, and 1,802 were slightly infested. Treatment. See page 77. ABATTOIR INSPECTION. See discussion, page 77. As the Armed Tape- worm is more dangerous to man than the un- armed form, the abattoir inspection for Cysticercus cellulosaeis more important from a hygienic stand- point than the inspection for C. bovis. Position of the parasites in hogs. The Pork- measle Bladder Worm is found in the muscles, especially in the abdominal muscles, the muscular portion of the diaphragm, the psoas, tongue, heart, the muscles of mastication, intercostals, muscles of the neck, the adductor of the hind legs, and the pectorals. These parts are shown by fig. 83. Particular stress should be laid FIG. 80. Segment of Pork- measle Tapeworm (Thcnia solium) in which the uterus is ahont half developed. X 2. (A f ter Leuckart, 1880, p. 666, fig. 295.) FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 93 upon an examination of the tongue and muscles of mastication, the muscles of the shoulder, neck, and diaphragm. The parasite of hogs which is most liable to be mistaken for C. cellu- losae is the large bladder worm with a long neck (C. tenuicollis, p. 06). The latter form, which is not transmissible to man, occurs under the serous membranes of the body cavities, but is not found in the muscles; it is much larger, and is provided with more hooks (28 to 40) than C. cellulosae (22 to 28). Frequency of Cysticercus cellulosae in liogs. Satisfactory statistics regarding the presence of this parasite in American hogs are lacking; we know, however, the American hogs are comparatively free from this worm. The statistics for Prussia are quite complete, the proportion of infested hogs being as follows: 1876 to 1882. One hog infested in every 305 hogs examined. (Johne, after Ostertag.) 1886 to 1893. One hog infested in every 637.5 hogs examined. ' The proportion of measly hogs appears to vary in different localities. Thus at the Berlin abattoir the average for ?even years was 1 infested hog to every 173 hogs examined (Ostertag). In south Germany the parasite is said to be rare. It is much more common in the eastern Prussian provinces than in the western, as shown by Ostertag in the following statistics for 1892: Regierungsbezirk. Propor- tion. Regierungsbezirk. Propor- tion. 1-28 1:865 1 -80 1:975 1:108 Diisseldorf 1 : 1070 | 1 : 187 > 1:19DO \ Entire Prussia 1 : 1290 Frankfurt > 1:250 Eastern provinces 1:604 The hogs imported into Germany from Russian Poland, Galicia, Bohemia, and Siberia were infested in much higher proportion than the German hogs ; in some of the importations the proportion ran as high as 50 per cent (Ostertag). 1 The totals of the following table do not agree with the totals published in Ger- many, but are made upon the details given for the various years. Several errors in addition were noticed in the German statistics. Year. Hogs inspected. Hogs in- fested with C. cellulosae. Authority. 1886 4, 834, 898$ 5,486,4164 6, 051, 249J 5, 500, 678J 5,590,512 6,550,182 6, 134, 559 6,251,776 10, 126 11,068 10, 031 8,373 5,492 7,689 9,364 10, 640 1 Veroff. d. kais. Gesuridheits- ( amtes, 1891, p. 244. 1 Veroff. d. kais. Gesundheits- j amtes, 1894, p. 208. Veroff. d. kais. Gesundheits- amtes, 1895, p. 347. 1887 1888 1889 1890 1891 1892 1893 Total 46, 400, 272 72, 783 94 INSPECTION OF MEATS FOR ANIMAL PARASITES. Influence of the age of the host. According to Gerlach hogs over six months old will not become infested with this parasite, but this is not admitted by Fischoder. Disposition of measly porJc. See disposition of measly beef, p. 81. Since Taenia solium is more dangerous than T. saginata, the regulations concerning the disposition of measly pork should be even more rigid , than those concerning V _ . - ** III \ measly beef. 1 orkof this character can of course be sold under declaration, but even this is not advisable unless the meat is first rendered non-in- fectious. Cases of so-called " single in- fection" 1 should be treated the same as cases of moderate in- fection. I n very heavy infections (up to 20,000 bladder FIG. 81. Gravid segment of Pork -measle Tapeworm (Taenia solium) , WOrmS may OCCUr ill showing the lateral branches of the uterus, enlarged (original). ei'r,o-lo di OlllglcJ pork is watery and pale; it decomposes easily, and has a disagreeably sweet taste. Such cases should, of course, be condemned to the tank. Cooking. According to Perroncito, C. cellulosae dies at 45 to 50 C. (= 113 to 1220 F.). (gee also p. 81.) It dies in 1 minute at 50 C. Storage. Living specimens of C. cellulosae have been found in pork twenty-nine days after slaughtering (Eail- liet). After fourteen to nineteen days of cold storage at 10 to 15 C. the para- sites are said to be dead; the protoplasm has become viscid, bluish opaque, and the books have fallen. More observations are needed upon this subject. Effects of electricity. Glage has experi- mented some with electricity in order to kill the parasite of pork measles, but further study in this line is desirable before the method is adopted. FIG. 82. Egga of Pork-measle Tape- worm (Taenia solium) : a, with primitive vitelline membrane; b, without primitive vitelline mem- brane, but with striated embryo- phore. X450. (After Leuckart, 1880, p. 667, fig. 297.) THE ADULT AND LARVAL TAPEWORM IN MAN. See discussion, page 83. It should always be recalled that the Armed Tapeworm is more dangerous than the Unarmed Tapeworm, since, as already stated, the larva as well as the adult may develop in man. 1 During the year 1889-90 Berlin, Prussia, found 373 cases of alleged single infec- tion ; of these, 56 cases were afterward shown to contain more than one parasite. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 95 Treatment. See page 87. C ysticercus cellulosae in man. This infection may take place in differ- ent ways; a patient may either soil his hands with the microscopic ^ggs during defaecation and afterward swallow the eggs; or, through a reverse peristaltic movement of the intestine, gravid segments may be carried into the stomach, where the shells will be destroyed, thus free- ing the embryos. An infection through a contaminated water supply may also take place. (See Life history, p. 90.) In man the bladder worm may develop in the muscles, the eye, and the brain. The following statistics upon the distribution of the worm in various parts of the body have been compiled from different sources : Locality. Parasite found in Total number of cases. Authority. Brain. Muscles. Heart. Lungs. Under skin. Liver. Dresden } 72 11 6 5 { l i 13 6 1 } 6 / 22 \ I* 87 21 6 5 JMuller. Dressel. Haug (1874-1885). Gribbohm. Sievers. Erlangen 3 3 2 2 (?) (1\ Total 117 32 9 3 5 2 155 The following statistics refer to the presence of this parasite in the eve: Locality. Total num- ber of patients or bodies. C. cellu- losae in the eye. Authority. ( 80,000 80 von Grafe. ? 30, 000 1 Hirschberg (1886-1889). France 1 43, 000 60, 000 1 30,000 7 Mauthner j" arasl * e ln crystaum lens. According to Virchow, the proportion of cysticercus in the human cadavers dissected in Berlin has been reduced from 1:31 (before the introduction of meat inspection) to 1:280 (since the introduction of meat inspection). The following statistics, collected from various sources by Blanchard, refer to post-mortem examinations : Locality. Number of post- mortems. Number infected. Proportion infected. Switzerland : 2,500 1 Per 1,000. 2.5 Basel 1,100 .0 1,914 6 1.13 Germany : jjiel G 6.7 n i 11.3 ~R r 16.4 r r 12.5 Prevention. See page 88. 96 INSPECTION OF MEATS FOR ANIMAL PARASITES. 21. The Thin, or Long, Necked Bladder Worm (Cysticercus tenuicoUis) of Cattle, Sheep, and Swine, and its adult stage, The Marginate Tape-worm (Taenia marginata) of Dogs and Wolves. [Figs. 84-87A, 88, 89B, 90-93.] Still another bladder worm, which is by no means uncommon in the animals of this country, occurs in the body cavity of cattle, sheep, swine, and other animals, attached to the dia- phragm, omen turn, liver, or other organs. When eaten by dogs or wolves, it de- velops into the Marginate Tapeworm, which was formerly confused with T. solium of man, and gave rise to the er- roneous idea that the Pork-measle Tape- worm occurs in dogs as well as in man. LARVAL STACK (Cytticercus tcnnicollis). For anatomical characters, compare fig. 84 with key, p. 21. SYNONYMY. Taenia hydatoidea Pallas, 1760; T. hydatigcna Pallas, 1766, pro parte; Hydra hydatula Linnaeus, (1766); Vermis resicularis eremita Bloch, 1782 ; Hydatigena orbicularis Goeze, 1782 ; H. globoaa Batsch, 1786 ; H. oblonga Batsch, 1786; Feaicaria orbicularis Schrank, 1788; Taenia simiae Gmelin, 1790; T. ferarum Gmelin, 1790; T. caprina Gmelin, 1790; T. ovilla Gmelin, 1790; T. rerrecina Gmelin, 1790; T. bovina Gmeliu, 1790; T. apri Gmelin, 1790; T. (jlobosa (Batsch) Gmelin, 1790; Hydatula solitaria Yiborg, (1795); Cyslicercus claratus Zeder, 1803 ; C. simiae (Gmelin) Zeder, 1803; C, caprinns (Gmelin) Zeder, 1803; C. tenuicoUis Rudolphi, 1810; C. risceralis simiae Rudolphi, 1810 (T. sirniae Gmelin, renamed); C. lineatus Laennec, 1812; C. oris Cobbold, 1865; Monostomum licpalicum SHI* Willach, 1893; " Cys- ticerkus" tenuicoUis of Schneidemiibl, 1896. PRE-LINNAEAN NAMES. Hydatides Bartholini, 1673; Verities vesiculares Hartmann (1685), quoted by Pallas as Hydatis animata; Lumbricus hydropicm, Tyson, 1691. HOSTS. Cattle, sheep, swine, deer, and other animals. (See pp. 137-143.) ADULT STAGE (Taenia marginata Batsch, 1782). For anatomical characters, compare figs. 85-89 with key, p. 101. SYNONYMY. See also pp. 89-90. Taenia solium Linnaeus, 1758, pro parte ; T. cateni- formis Goeze, 1782, pro parte; T. marginata Batsch, 1782; T. lupina Schrank, (1788); T. cateniformis /3. lupi Gmelin, 1790; Halysis marginata (Batsch) Zeder, 1803; also "T. solium" of dogs, of several medical authors. BIBLIOGRAPHY. For technical discussion, see Deff ke, 1891. HOSTS. Dog and wolf. (See pp. 137-143.) Fio. 83. Half of hog, showing the por- tions most likely to become infested with pork measles. (After Ostertag, 1895, p. 387, fig. 79.) See p. 92. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 97 FIG. 84. The Thin-necked Bladder "Worm (Cysticer- cua tenuicollis), with head extruded from body, from cavity of a steer, natural size (original). Life history. In tracing the life history it is best to begin with the egg, produced by the adult tapeworm in the intestine of dogs. These eggs, containing a six- hooked embryo, escape from the dog with the excrements and are scat- tered on the ground, either singly or confined in the escaping seg- ments of the tapeworm. Once upon the ground they are easily washed along by rain into the drinking water, ponds, or brooks, or scat- tered on the grass. Upon being swallowed with fodder or water, they arrive in the stomach of the intermediate host (cattle, sheep, etc.), where the eggshells are de- stroyed and the embryos set free. The em- bryos then traverse the intestinal wall, and according to most authors arrive either act- ively, by crawling, or passively, by being- carried along by the blood, in the liver or lungs, where they undergo certain transfor- mations in structure. While still in the finer branches of the blood vessels of the liver, which they transform into small irregularly shaped tubes about 12 to 15 mm. long and 1 to 1.5 mm. broad, the embryos lose their six hooks, and develop into small round kernels, which are generally situated at one end of the tubes. The embryo can first be seen about four days after infection. The " scars" (figs. 91 and 92) described in the liver of animals infested with Cysticercus tenuicollis are nothing more nor less than these tubes, or altered blood vessels, caused by the growth and wandering of the parasites. In a shoat which Leuckart infected with eggs, and which he killed twenty-three days after the infection, he found two young cysticerci in the liver 6 to 8.5 mm. long and 3.5 to 5 mm. broad. In the smaller parasite no head was visible; in the larger, one end was slightly FIG. 85. The Marginate Tapeworm (Taenia marginata), natural size (original). differentiated and evidently represented tlie anlage (primordium) of the 5257 No. 19 7 98 INSPECTION OF MEATS FOR ANIMAL PARASITES. scolex that is, the head and neck in course of development. The por- tion which was destined to give rise to the head arid neck was a small projection extending into the cavity of the hydatid. At about this stage, or a few days later, the parasites leave the liver, fall into the body cavity, and become encysted again in the organs mentioned above. A month after infecting another shoat, Leuck- art found cysticerci in the body cavity, with partially developed suckers and hooks. Six weeks after the infection of another shoat, he found cysticerci 15 mm. long encysted in the omentum, and with fully developed scolex. Three months after infecting a lamb, he found cysticerci twice as large. Experiments have also been made by other authors (Baillet, Kiich- enmeister, Kailliet, etc.), most of them agreeing with Leuckart's experiment. Curtice, however, takes a somewhat different view, that is, he considers the liver as a place of destruction for the young parasites, rather than a normal place for their development ; he also claims that the embryos which may even travel the entire length of the intestine of the intermediate host, traverse the intestine and arrive directly in the position where they complete their larval development without first passing through the liver. After developing into the full-grown bladder worm, the parasites remain unchanged until they are devoured by a dog or wolf, or until, FIG. 86. Head of theMarginate Tapeworm (Taenia margi- nata). X 17. (Original.) FIG. 87. Small and large hooks of (A) (Taenia marginata), (B) T.terrata, and (C) T.cocmtri's: a, small hooks ; b, large hooks. X 480. ( After Deffke, 1891, PI. II, fig. 9.) after an undetermined length of time, they become disintegrated and more or less calcified. If the hydatid is devoured by a dog or wolf, either when the latter prey upon the secondary host or when the dog obtains the cyst at a slaugh- terhouse, the bladder portion is destroyed, the scolex alone remaining FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 99 intact in tbe digestive fluids. The head holds fast to the intestinal wall with its suckers and hooks; by strobilatioii (transverse division) it I FIG. 88. Sexually mature segment of the Marginate Tapeworm (Taenia marginata) : cp, cirrus pouch; gp, genital pore; n, nerve; ov, ovary; sg, shell gland; t, testicles; tc, transverse canal; ut, uterus; v, vagina ; vo, ventral canal ; vd, vas deferens ; vg, vitellogene gland. Enlarged. ( After Deffke 1891 PI. I, fig, 1.) gives rise to the segments, which, as we have already seen, together with the head, go to make up the adult tapeworm. Eeproductive organs of both sexes develop in the separate segments, and eggs are FIG. 89 Gravid segments, showing the lateral branches of the uteri of (A) Taenia serrata, X4; (B) T. marginata, X 6; (C) T. coenurug, X 10-15. (After Leuckart, 1880, p. 720, fig, 308.) produced within which are developed the six-hooked embryos, the point from which we started out. The disease in cattle, sheep, and hogs. As a rule, this bladder worm is a comparatively harmless parasite, a light infection having little or no 100 INSPECTION OF MEATS FOR ANIMAL PARASITES. effect upon the host. A heavy infection may, however, prove fatal to young animals. So far as I know, only one case is on record where this parasite has proven fatal to cattle probably from the fact that no severe infections have yet been found ; and from our present knowledge of the subject, it can be confi- dently asserted that a slight infection has little or no effect upon this host. In experiments which have been made upon sheep and pigs, it has been noticed that heavy infections have not only produced decided symptoms but have proved fatal to the animals named. Several cases (Leuckart, Zschokke, Railliet) are also reported where pigs have died from the effects of these parasites which were accidentally acquired with their food. In all of these cases the infection was very heavy. The parasites had caused peritonitis and pleurisy by their migrations from the liver and lungs to the body cavities. In a case recently described by Railliet, a shoat of two months succumbed to the disease. Baillet made numerous experiments on lambs and on young goats, the animals dying in ten to fifteen days (a primordium of the scol ex was noticed on cysts fifteen days old). In one of Railliet's experiments a goat died in five days. There is no way of positively diagnosing when an animal is infested with these larvae, as the symptoms noticed on experimental animals apply FIG. 90. Egg of the Mar- ginate Tapeworm (Tae- nia marginata) with six-hooked embryo, greatly magnified (original). m FIG. 91. Portion of the liver of a lamb which died nine days after feeding with eggs of the Harginate Tapeworm (Taenia marginata), with numerous "scars," due to young parasites. (After Curtice, 1890, PL X, fig. 1.) equally well to other infections. Diagnosis being uncertain or even impossible, it is useless to discuss treatment, except to remark that the parasite can not be reached with medicines; so that anj v treatment advised would be simply that advocated for pleurisy or peritonitis. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 101 Prevention is a comparatively easy matter and lies in keeping dogs free from tapeworms. ABATTOIR INSPECTION. So far as the question of using beef, mutton, or pork from animals infested with Cysticercus tenuicollis as food for man is concerned, this parasite is of no importance whatever; for although several authors have attempted to infect themselves with tapeworms by swallowing this larva, all such experiments have been negative. Differential diagnosis. Infection of cattle, sheep, and hogs by C. tenuicollis may be mistaken for infection by C. bovis (p. 71), C. cellulo- sae (p. 89), Echinococcus (p. 113), and even for tuberculosis, but the differ- ential diagnosis should not be difficult. For the differences between the Long necked Bladder Worm and the other three larvae, see the discus- sions of those parasites. The condition of the corresponding lymphatic glands in tuberculosis of the host, as well as the hooks and calcareous FIG. 92. Cross section of the liver of a lamb which died nine days after feeding with eggs of the Margi- nate Tapeworm (Taenia marginata) . (After Curtice, 1890, PL X, fig. 2.) corpuscles of C. tenuicollis, allow a differentiation of degenerated and calcified specimens of this parasite from tuberculosis. Frequency of C. tenuicollis. In some countries the larval stage is common, especially in sheep. Olt found it in 26.4 per cent of the sheep (132 times in 500 sheep) examined at Stettin, Germany. It occurs in America, Europe, Africa, and probably elsewhere. In connection with this parasite it is necessary to consider the adult tapeworms found in dogs. THE ADULT TAPEWORMS OF DOGS. The Marginate Tapeworm is unfortunately not the only tapeworm in the dog which proves harmful to our flocks. The following key will aid in determining the most common canine forms and show the source of infection : KEY TO THE ADULT TAPEWORMS OP DOGS. [For the forms transmissible to cattle, sheep, and swine follow Roman type.] (1) Four suckers on the head Family Taeniidae, 2. Tivo suckers on the head; genital pores rentro-median Bothriocephalus. 102 INSPECTION OF MEATS FOR ANIMAL PARASITES. (2) Head armed with hooks ; genital pores marginal 3. Head not armed with hooks ; genital pores rentro-median Mesocestoides. ] (3) Head armed with a double row of hooks; genital pores on only one side of each ( segment I. ] Head very small, ivith about GO hooks arranged in 4 rows ; body 10 to 40 cm. lonij, \ ivith SO to 120 quadrate to elliptical segments, the largest of which, may measure 1.5\ to S mm. broad by 8 to 10 mm. long ; eggs in round capsules, about 250 in number, with 5 to 20 eggs in each capsule; eggs measure 43 to 50 jj,; larval stage in fleax and I lice, which may transmit the worm to dogs or to man IHpylidium caninum. I (4) Body small, 4 to 5 mm. long, with only 3 to 4 segments, the largest of which may! measure 0.6 mm. broad by 2 nun. long; 28 to 50 hooks on the head; about 60 ] testicles present in a segment ; einbryophores 32 to 36 ft by 25 to 30 ji. The] eggs are transmissible to man, oxen, sheep, pigs, horses, and other mammals, and develop into the larval stage (the Echinococcus hydatid), which is veryl dangerous. All dogs found infested with this worm should be killed and! burned Taenia echinococcus, p. 113. 1 Body much larger and with many more segments 5. j (5) Segments somewhat broader than long, or square, or longer than broad 6. Segments much broader than long, except the distal segments ivhich suddenly elongate; j head small, with 26 to 34 hooks; genital pore unusually large and prominent* embryophores 30 /J.. Larval stage develops in the reindeer Taenia Krabbet. ] (6) Ventral root of hooks simple ...... 7. j Ventral root of smaller hooks bifid ( After Curtice, J 1890, PI. X, fig. 3a.) female dogs, and that tapeworms are more common in large dogs and in dogs from 1 to 3 years old than in small dogs and animals under 1 year of age. The best method of diagnosis is to examine the faeces for segments or eggs. In some cases the attention of the diagnostician is attracted to expelled segments by the dog's licking around the anus or his "slid- ing" on the anus. A mild laxative will generally result in the expul- sion of a few segments, and this method of confirming suspicions is occasionally used. Even if segments are not found in the excreta, it is a good plan to treat the dogs for tapeworms, so as to remove all doubts as to their presence. Dogs which come in contact with herds should certainly be treated occasionally to prevent any possibility of infecting the stock animals. It will be noticed that the larval stages of three of these tapeworms are injurious to stock animals, namely, T. maryinata, T. coenurus, and T. echinococcus. The larvae of the others are of comparatively little economic iinpor- 104 INSPECTION OF MEATS FOR ANIMAL PARASITES. tance, although it may be remarked that the larvae of T. serrata are sometimes fatal to rabbits, while the adult D. caninum sometimes occurs in children, who become infected with it by too intimate association with dogs. While playing with dogs they unconsciously get fleas upon themselves which they afterwards swallow. The fleas are digested and the larvae contained in their bodies, becoming free in the intestine, develop into tapeworms. It is very difficult to distinguish between the adult forms of T. coenu- rus and T. serialis. The later is quite common in America. If T. echinococcus is found to be present in a dog, the safest plan is to kill the dog and burn its carcass. The larval form of this parasite is so dangerous to man that it is not safe to have the dog around or to handle it, as is necessary in administering the treatment. Taenia marginata develops in the dog, as stated elsewhere, in about ten to twelve weeks ; T. serrata in about eight weeks ; T. coemtrus in two and a half to eight weeks. The table following, giving the more common tapeworms in dogs, has been compiled from the various sources cited, and shows the compara- tive frequency of the various forms. There are as yet no extensive statistics for this country. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 105 Authority. 1 ~ . 1 ^ | 1 tg 1 S^Jp,,. o) n . -2 ^ ^ re * 1 From time to time Hassall, Curtice, Stiles, and several volunteer assistants have examined dogs in this laboratory, but none of the examinations except those made by Son mer. were conducted with a view to establishing statistics, and hence no exact records have been kept. I have personally seen adults of T. mariiinata, T. terrata, T. serialU T. echinococcus, and D. caninum, and larvae of the four species of taenia collected in various parts of the United States. 2 After Deffke, 1891, p. 259; Krabbe's article not in Washington. 3 Recorded as '"T. inermis"~T. pgeudo-cucurnerina=M. lineatug. 4 Also observed one case of T. serialig (see B & C., 1879, p. 297), hut apparently not in this lot of dogs. "Thomas is not certain that these specific determinations were "invariably correct.'' 'This is recorded from the first 13 dogs examined (see Thomas, 1882, p. 436) ; no mention is made of the liothriocevhalus in the other dogs. Jiothrio- cephalug. *l oooo"' 1*1 . 6 fc OOOiOrH _ *" i-i *" cr o o J 1 Mesocestoi- deg lineatug. * H o o 6 S S- o o ? : fc .ft . Dipylidiwn caninum. ti a" 9 " 01 ""* "* ?J '"* 100 * 1 6 5 " O5 * Taenia serialig. *1 d ^ = " ! i il : : i Taenia coenurus. * * t-IM ooooOi-i c 1.8 2,418 1.5 1. 938 1. 5 1, 721 1. 2 739 .5 188!) 90 ' 1891191 1891 o>) 189" 9;j . SHEEP. 1888 89 338, 798 5,041 1.4 3,363 0.9 188') 00 430, 362 5,479 1.2 2,742 .6 1890 91 371, 943 4,595 1.2 2,059 .5 1801 92 367, 933 4,435 1.2 1,669 .4 189''-9:j 355, 949 3,331 .9 1,161 .3 HOGS. \ 1888 89 ,.'.... 479, 124 5,910 1.2 5,285 1.1 i 1889 90 '- 442, 115 6, 523 1.4 5,078 1.1 J890 91 472, 859 5,083 1.07 3,735 .07 1891 92 . 530. 551 6,037 1.1 4,374 .08 1892 93 518, 073 6,785 1.3 4,312 .08 I 1893-94 in all 13,424 lungs and 6,283 livers. (Berichte ii. d. stiidtische Vieh- u. ! Schlacbthf.) i These statistics show that from 1888-89 to 1892-93 there has been k'a reduction in the number of organs condemned for hydatids both in [ cattle and sheep, which must be attributed to the system of abat- Roir inspection, and which must necessarily result in a corresponding Iflecrease in hydatid disease in man. This reduction is not so apparent ffl&moDg hogs, but it -must not be forgotten that Berlin slaughters large Kmmbers of hogs imported from districts in which the slaughterhouse inspection is exceedingly superficial. We saw above that some Ger- nan importations of hogs from Russian Poland, Bohemia, etc., were mn feet ed with Cysticercus cellulosae to 50 per cent, and hogs which are Kept in such a manner as to allow this infection will certainly also bring np the German statistics of hydatids. I am strongly inclined to give Bunch greater importance to the Berlin statistics than appears from the percentages of infection among the hogs. THE ADULT TAPEWORM IN DOGS. (See p. 101.) It seems to me entirely impracticable to attempt to guard against hydatid disease by trying to definitely diagnose the pres- Kuce of the adult worms in dogs. If, however, the worm is found in 124 INSPECTION OF MEATS FOR ANIMAL PARASITES. dogs, the latter should be killed and burned. The hydatid is altogether! too dangerous a parasite in man to warrant a person's treating a . It was found in France. 29. The Broad Moniezia (Moniezia expansa) of Cattle, Sheep, Goats, etc. [Figs. 116-119.] SYNONYMY. ? Taenia orina Goeze, 1782; ? Halysis ovina (Goeze) Zeder, 1803; ? T. expansa Rudolphi, 1805 (nonien nudum); T. expansa Rudolphi, 1810; Alyselminthus ejrpansus (Rudolphi) Blainville, 1828; Moniezia ejrpansa (Rudolphi) R. Blanchard, 1891; Taenia (Moniezia) expansa of Braun, 1895. This worm is quite common in America and Europe, both in cattle and sheep. 30. The Triangle Moniezia (Moniezia triyonopliora) of Sheep. [Figs. 120-121.] SYNONYMY. Moniezia triyonopliora Stiles fe Hassall, 1893; Taenia (Moniezia) tri- gonophora (Stiles & Hassall) Braun, 1895. Also T. expansa and T. Benedeni pro parte of some authors. This is rather a common parasite of American sheep, and is also found in France. It takes its name from the triangular arrangement of the testicles. I have seen one serious outbreak of disease in sheep due in part to this parasite and in part to the twisted wireworm (Strongylus contortus) of the stomach. Genus THYSANOSOMA. Represented by one species in North America and South America and one species in Europe. 31. The Fringed Tapeworm (Tliysanosoma actinioides) of Sheep, Deer, etc. [Figs. 122-124.] SYNONYMY. Thysanosoma actinioides Diesing, 1835; Taenia fimbriata Diesing, 1850 [nee Batsch, 1786]; " Taenia expansa" misdet. pro parte, of Faville, 1885; Moniezia fimlriata (Diesing) Moniez, 1891. The Fringed Tapeworm is found in North America and South America, and forms at times a veritable scourge to the sheep industry of the Western plains. Disease. The disease in sheep caused by the Fringed Tapeworm has been studied in detail by Curtice (1890, pp. 91-109), who considers that next to scab it is the most important sheep disease of the Western plains. The financial loss it causes is quite extensive, and results from the failure of the lambs to fatten, the lessening of the wool, and the weakening of the animals so that they can not withstand the cold win- ter weather. The parasites develop slowly, and are present in consid- erable numbers before their presence is suspected. Toward September the lambs fail to grow as they should; in November the symptoms are FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 129 FIG. 117. Three views of the head of the Broad. Moniezia (Moniezia expansa). X17. (After Stiles, 1893, PI. V, figs. 1-16.) See p. 128. quite marked. First, the worms produce a local irritation of tlie intes- tine, which finally develops into a chronic catarrhal inflammation; their presence in the gall ducts produces similar results and obstructs the flow of bile; infected lambs are large headed, undersized, and hide- bound; their gait is rheumatic and they appear more foolish than the other sheep, standing of- tener to stamp at the sheep dogs or herders, and lag- ging behind the flock when driven; the general symp- toms are those of malnutri- tion, and Curtice considers them nearly identical with the symptoms of the loco disease"; in fact, he states that it is extremely difficult I \ to distinguish between the two diseases, and believes that the fact that the worms "may tend to produce de- praved appetites and a morbid craze for a particular food is also reason for suspecting that the loco disease may depend on the tape- worm disease." General systematic disturbances result from malnu- trition; the usual fat is absent; serous effusions are noticed in the body cavities, serous infiltration in the connective tissue. Treatment. Curtice found that powdered preparations of pumpkin seed, pomegranate-root bark, cusso, k a m a 1 a, male fern, and worm seed were of no avail, a failure due, he maintains, to the anatomical structure of the sheep's stomach and "*&' -:-;K& method of administration; FIG. 118 -Sexually mature segments of the Broad Moniezia ^ me didne COUld be USed (Moniezia expansa): cp, cirrus pouch; ig, mterproglottidal glands; rs, receptaculum seminis; sg, shell gland; t, testi- to dislodge the parasites cles; v, vagina; vg, vitellogene gland. Enlarged. (After from the S'all ducts Stiles, 1893, PI. VI, fig. 4.) See p. 128. Personally, I have never treated sheep for the Fringed Tapeworm, but I would suggest the advisability of trying the method described on pp. 133-135. 32. Giard's Thysanosoma ( Thysanosoma Giardi) of Cattle(?), Sheep, and Swine( ?). SYNONYMY. Taenia o'villa Kivolta, 1878 [nee Gmelin, 1790] ; T. Giardi Moniez, 1879; T. aculeata Perroncito, 1882; Moniezia ovilla (Rivolta) Moniez, 1891; M. ocilla 5257 No, 19 9 130 INSPECTION OF MEATS FOR ANIMAL PARASITES. vur. madlcnta Moiiiez, 1891; Thysanosoma (iiardi (Mouiez) Stiles, 1893; Th. onlla (Rivolta) Railliet, 1893; Taenia Brandtl Cholodkowsky, 1894; Th. ovillum (Rivolta) Railliet, 1895. This peculiar tapeworm has been found in sheep in France, Italy, Germany, and Russia, and has been recorded once in hogs ; its occurrence as a normal parasite in both hogs and cattle is doubtful. (See pp. 126-127.) Genus STILESIA. Two species of this genus are found in sheep, but neither 'form is yet recorded for this continent. 33. TheGlobipunctate Stilesia (Stilesia ylobipunctata) of Cattle(?) and Sheep. SYNONYMY. Taenia globipunctata Rivolta (1874); T. oripunctata Rivolta (1874); Stilesia ylobipunctata (Rivolta) Railliet, 1893. Found in sheep in Italy and India ; its occurrence in cattle is doubtful. (See p. 126.) 34. The Centripunctate Stilesia (Stilesia centripunctata) of Cattle(?) and Sheep. SYNONYMY. Taenia centripunctata Rivolta (1874); Stilesia centripunctata (Rivolta) Railliet, 1893; Taenia (Slilesia) centripunctata of Braun, 1895. Found in sheep in Italy and Algeria ; its presence in cattle is doubtful. (See p. 126.) FIG. 119. Gravid segment of the Broad Moniezia (Moniezia expansa). enlarged.- (After Stiles, 1893, 1>1. VI, fig. 6.) See p. 128. Life history. Nothing is positively known about the life history of any of the adult tapeworms of cattle or sheep ; but from analogy we may assume that the life cycle is similar to that of other cestodes, namely, that the parasite runs through two stages the adult form, in the intestine of cattle and sheep, and a larval state (a cysticercus or a cysticercoid), which will be found as a parasite in an intermediate host, probably some invertebrate animal, as an insect, snail, or worm. The intermediate host will become infected from the eggs in the faeces of the cattle and sheep, and the latter will become infected by accidentally swallowing the intermediate host. While this is what seems to us at present as the probable life history of the bovine and ovine tapeworms, it must be distinctly remembered that no one has as yet been able to positively make out the complete life cycle. In fact, some authors (Curtice and others) do not think that it is necessary for these worms to pass through any intermediate host, but they believe that the embryos (in the eggs) are swallowed by the cattle and develop directly into adult worms. This theory, however, is contrary to analogy, and although this Bureau has repeatedly attempted FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 131 to infect animals in the manner indicated, none of the experiments can be looked upon as supporting Curtice's views, for we were unable to pro- duce an infection. One of the following experiments, gh'en as illustrations, might at first sight seem to support Curtice's theory, but can equally well be ex- plained otherwise: (1) September 2, 1891. A 6-months-old lamb fed with thousands ( ! !) of eggs of M. expansa. October 2. Experiment animal showed ripe proglottids in droppings. The infec- tion, however, was totally out of propor- tion to tbe number of embryos fed, so that the lamb must have become infected in some other way. (2) September 10. Lamb fed with thou- sands of eggs of M. expansa at three differ- ent times within a week. September 30. Lamb killed and four-hour post-mortem held. Intestinal villi, etc., examined microscopically. Eesult totally negative. (3) September 10. Lamb fed with thou- sands of eggs of M. expansa five times within a week. Result negative. Experiments by Curtice and Eu- ropean authors must also be consid- ered as negative, for according to the published accounts of the infections [the possible sources besides direct ingestion of eggs were not suffi- ciently controlled. TAPEWORM DISEASE OF CATTLE AND SHEEP. For disease caused by the Fringed Tapeworm, see page 128. Source of infection. It will be impossible to make any definite ; statements upon this point until : thecomplete life history of the worms is known. Occurrence. Tapeworms are found iin cattle and sheep of all ages and FIG. 120. Portions of an adult specimen of the Triangle Moniezia (Moniezia trigonophora), natural size. (After Stiles & Hassali 1893, PI. VIII, fig. 1.) See p. 128. at all times of the year, but calves, lambs, and yearlings suffer more 132 INSPECTION OF MEATS FOR ANIMAL PARASITES, from the effects of the parasites than do older animals. They are occa- sionally found in animals in stalls, but are more frequent in animals which are in pasture, and are not so frequent in the winter and early spring as in the summer and fall. Worms (M. expansa or If. planissinm ) from G to 15 feet long have been found in lambs two to four months old, so that these parasites must grow to maturity very rapidly. Curtice computes the average growth at about 1 yard per month. Symptoms. There can be no question that sheep and cattle may liar Tbor a small number of tapeworms with comparatively little or no ill ^effects, for these worms are found at abattoirs in sheep which are in excellent condition at the time of slaughter. The younger the animal and the greater the infection with worms, the more serious the effects of the disease; but if able to pass through a certain period the animals are very apt to recover, for the worms seem to shed their segments quite suddenly, leaving the hosts with but small tapeworm strobila, and by the time the parasites again attain a greater length the animals may have gained in condition and strength to withstand the disease. Tapeworms affect their hosts in several ways. By assimilating the FIG. 121. Sexually mature segments of the Triangle Moniezia (Moniezia triyonophora) : cp, cirrus pouch ; dc, dorsal canal ; ig, interproglottidal glands ; n, nerve ; ov, ovary ; rs, receptaculum semiuis ; sg, shell gland; t, testicles; v, vagina; vc, ventral canal; vd, vas deferens; vg, vitellogene gland. Enlarged. (After Stiles & Hassall, 1893, PI. IX, fig. 4.) See p. 128. nourishment in the intestinal tract of their hosts, they rob the latter of food; when present in large numbers, they may cause stoppage of the bowels, irritate the bowels, leading to non assimilation of food and reflexly to the nervous symptoms. The clinical history is not very clearly defined from infection with other intestinal parasites, especially with the twisted strougyle (Stronciylus contortus). As the animals lose flesh, become poorer, and hidebound, their gait becomes unsteady, the fleece becomes dry and harsh, little yolk being present; the appetite and thirst may increase; diarrhoea is frequent in severe infections, and becomes more pronounced as the disease advances. The animals may at last become completely exhausted and die. Diagnosis. Suspicion of tapeworm disease being aroused by the general poor condition of the animals, a positive diagnosis may fre- quently be made by finding the cast-off segments in the droppings, or around the anus under the tail. A microscopic examination of the faeces for eggs is practicable only for experts. In case of death of one of the flock, it is best to make a careful post-mortem, examining the fourth stomachfor the twisted strongyle and the intestines for tapeworms. This can easily be done by opening the intestine in a tub of warm water. FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 133 Treatment^ The first thing to do in treating sheep and cattle for tapeworms is to confine the animals in a comparatively small yard and to withhold solid food the night before dosing. The animals should be kept confined until the worms are passed, then all the faeces should be collected and burned, or buried in quicklime. Schwalenberg reported good results with kamala, dose for a lamb 3.75 grains (about 1 dram); also with cusso (kousso), close for a lamb 7.5 grams (nearly 2 drams) 5 still better results with kosiu (koussiu), dose for a lamb 12 centigrams. Picric acid, dose 0.6 to 1.25 grams (10 to 20 grains), made into pills with meal and water, is recommended by some authors. It should be followed with a cathar- tic (a 4-ouuce dose of Epsom salts or a 4-ouuce dose of any of the l)land oils). Two-ounce dose of powdered male fern root, or, still better, the ethereal oil of male fern in dram doses, is recommended by some veterinarians. It can be given in combination with 2 to 4 ounces of castor oil. Frohner (1889) gives the following recipes: Take koussin, 3 grains, and of sugar 10 grains, mix, and give at one dose. The dose of tansy is from 2 to 6 drams. It forms one of the chief ingre- dients of Spinola's worm cake, which is fed to lambs as a pre- ventive against worms. The recipe, sufficient for 100 sheep, is as follows: Take of tansy, calamus root, and tar, each 2 pounds; of cooking salt, 1J pounds; mix these with water and meal, make into cakes, and dry. This is an old and oft-repeated recipe, but I can not vouch for its efficiency. (Curtice, 1890.) Powdered areca nut may be given to lambs in doses of 1 to 3 drams. If no passage occurs, follow in three or four hours with a cathartic. In the recent experiments with bluestone by Hutcheon, in South Africa, against wire worm disease in sheep, ithas been found that the same treatment expels tapeworms. Caution. Repeated accidents have happened from using too strong a solution or too large doses, or in giving it in such a way that the medicine gains access to the lungs. Dr. Hutcheon's method of procedure, which is here given in detail, is safe in the hands of the average farmer if the directions are followed. The person who gives stronger doses than indicated, or who is careless about the measurements, must take the en- tire responsibility of the miscarriage of the treatment. It is a good plan to make up a smaller quantity of the solution and try it upon a few sheep before attempting to dose the entire flock. FIG. 122. Adult specimen of the Fringed Tape- worm ( Thysano- soma aetinioides) . (After Stiles, 1893, PI. XI, fig. l.) See p. 128. 1 In this connection consult Curtice, 1890, pp. 120-121. 134 INSPECTION OF MEATS FOR ANIMAL PARASITES. (a) To prepare the mixture. Hutcheon lias changed his formula slightly from time to time, the latest published proportions (February 21, 1895) reading as follows (see footnote, p. 130) : Dissolve 1 pound avoirdupois (1 pound = 16*ouuces) of good, com- mercial, powdered bluestone (sulphate of copper) in 2 imperial quarts (= 2f quarts U. S.) of boiling water; when the bluestone is thoroughly dissolved add 6 imperial gallons ( = 26 imperial quarts = 7-f- U. S. gallons = 31'i U. S. quarts) of cold water, making in all 7 imperial gallons (or 8| U. S. gallons) of water. (See footnote, p. 136.) Use only bluestone which is of a uniform blue color; avoid that which is in conglomerate lumps with white patches and covered with a white crust. The equivalents of 1 pound avoirdupois and of 7 imperial gallons in other weights and measures are as follows: One pound avoirdupois = 1 ponntl 2 ounces 280 grains of apothecaries' or of imperial troy weight = 453. 59 grams of metric weight. Seven imperial gallons = 8 gallons 3 pints 3 fluid ounces 3 fluid diachms 56 minims (or practically 8 gallons 3i pints, or 8 gallons) of apothecaries' or wine meas- ure, U. S. =31.804409 liters (practi- cally 31^ liters) metric system. The farmer is cautioned against guessing at the weights and measures, for this is sure to result in too strong a solution, which will kill his animals, or FIG. 123.-Ventral and apex views of the lead of the tOO weak a Solution, which will Fringed Tapeworm (Thysanosomaactinioides). x 17. f a il to be effective. Scales aild (After Stiles, 1893, PL XI, figs. 2 and 2 6.) See p. 120. measures should be tested before they are used. If reliable scales are not at hand, buy the bluestone already weighed and have the exact weight in avoirdupois, apothe- caries', or metric system marked 011 the package. If a smaller quantity than the above is desired, this can be made up on the proportion of 1 ounce avoirdupois of bluestone to 44- U. S. pints of water. (b) Preparation of the animals. Fast the sheep or cattle twenty to twenty-four hours before dosing. If the fast is thirty hours (longer fasts are dangerous) an extra half gallon or a gallon of water should be added to the solution, as animals are more liable to suffer after a long fast. . (c) Size of the dose. Hutcheon has several times changed the size of the doses he advises, in some papers basing it on the imperial fluid ounce, in others on the tablespoon. The doses for sheep (in imperial ounces and in tablespoons) given below are his most recent (January 10, 1895) recommendations, and though based upon a solution with 5 per cent less water than the solution given above, they may be used for the weaker mixture. We have given several of the metric doses to sheep on the Bureau FLUKES AND TAPEWORMS OF CATTLE, SHEEP, AND SWINE. 135 Experiment Station, and the sheep showed 110 ill effects; on the con- trary they gained in weight. (See footnote, p. 130.) Age of animals. Approximate equivalents. Table- spoons, a Imperial. TJ. S. apothe- caries. Metric. 1 2 3 4 4i 4Jto5 5to5J About J fluid ounce. About 1| fluid ounces. About 2J fluid ounces. About 3 fluid ounces. About 3^ fluid ounces. About3ito3J fluid ounces. About3Jto4J fluidounces. About J fluid ounce. About 1J fluid ounces. About 2 fluid ounces. About 2f fluid ounces. About 3 fluid ounces. About 3 to 3J fluidouuces. About 3J to 3f fluid ounces. About 20 cc. About 40 cc. About CO cc. About 80 cc. About 90 cc. 90 to 100 cc. 100 to 110 cc. For a sheep 18 months old o "The tablespoon I refer to is the modern full-sized tablespoon (6 fluid drachms). The medicinal tablespoon contains exactly half an ounce." HUTCHEON. Be careful not to give a two-toothed young sheep as much as a full grown four-toothed sheep. Mistakes may occur in judging the age unless the teeth are examined. The doses should be measured off in bottles and the point of each dose plainly marked with a file. (d) Dosing. In dosing, use long-necked bottles, as castor-oil bottles, Worcester sauce bottles, or anchovy sauce bottles. Let one person set the sheep on its haunches and take its two fore- legs in his left hand, while he steadies the head with the right. Another person inserts the neck of the bottle into the mouth. The head of the sheep should not be raised too high, as in that case the solution may enter the lungs and kill the sheep. A safe rule is to raise the nose to the height of the animal's eyes. (e) Overdose. If, after dosing, any of the sheep seem to be suffering from an overdose, indicated by lying apart from the flock, not feeding, manifesting a painful, excited look and a spasmodic movement in its running, walking with a stiff gait, purging, the discharge being a dirty brownish color, take the affected animals away from the flock to a shady place and dose with laudanum and milk as follows : For a lamb 4 to C months old, 1 teaspoouful of laudanum in a tumbler of milk. For a sheep 1 year old, 2 teaspoonfuls of laudanum in a tumbler of milk. Eepeat half the dose in two to three hours if necessary. (/) After-treatment. The animals should not be allowed water for several hours after receiving their dose. Prevention. Preventive measures against adult tapeworm infection in sheep and cattle can be given only in the most general terms, as explicit directions can be based only upon a knowledge of the exact source of infection. The general preventive measures applicable to all intestinal parasitic diseases would apply in the case of tapeworm disease, namely: since the parasites are contracted by means of con- INSPECTION OF MEATS FOR ANIMAL PARASITES. taminated food or drink, prevent this contamination as much as possi- ble; feed high with pure food and water preceding and during the time of greatest infection; avoid overcrowding of pastures; isolate infected stock; and when treating medicinally treat the entire flock if possible. Contamination of food and drink. This generally takes place by allowing manure piles to drain into the water supply or into pastures In the case of adult tapeworms of cattle and sheep some other factors probably come into play. Feeding pure food and water. Grain, etc., should be fed from platforms or troughs, which should be kept clean; raised water troughs should be supplied, so that the animals need not be obliged to drink from stagnant pools. These water troughs should be occasionally cleaned. Many ranchmen have already learned that by feeding their lambs ex- tra grain dur- FIG. 124. Segments of the Fringed Tapeworm (Thysanosoma actinioides), ing the fall, not showing canals and ntrves, and (/) fringed border, (t) testicles, and (ut) 1 ' 1 *o fl ri uterus. Enlarged. (After Stiles, 1893, PI. XI, fig. 8.) See p. 128. losses been di- minished, but the lambs become larger and stronger as well as fatter. Avoid overcrowding of pastures. Overcrowding of pastures is one of the surest methods of keeping animals permanently infested with ani- mal parasites, since the chances of infecting the pasture are increased and, by being compelled to graze too close, the animals are more liable to infection from the germs of parasites found on the ground. Isolation of infected stoelc. This is always advisable, no matter what particular disease is present. 1 Treatment of the entire herd. This is advisable, since all animals which have been subject to infection stand a chance of having con- tracted disease, even if only in a light form; but light attacks of para- sitic diseases serve to reinfect pastures. ABATTOIR INSPECTION. The abattoir inspection for tapeworms in the intestines of cattle and sheep is of no importance whatever, since none of these parasites are transmissible to man in any stage of their development. If the drain- age of a slaughterhouse is not properly cared for, the surroundings form a concentrated area of infection. 1 Addenda to HutcJteon's Bluestone Treatment. At the moment of going to press after proof reading was completed, we have received from Hutcheon another article on this subject, dated 1897. He adopts practically the same doses given on p. 135, but changes the strength of the solution (see p. 134) to 1 pound of bluestoue to "40 whiskey bottlesful of water." This is practically 1 pound to 1\ imperial gallons (=9 U. S. gallons = about 34 liters metric) of water. We wish here to repeat and emphasize the advice given to the farmer on p. 133, to make up a smaller quantity of the solution and try it on a few sheep a few days before the entire flock is dosed. This will give him an opportunity to judge whether he has made a mistake in weights and measures in mixing the solution. II. COMPENDIUM OF THE PARASITES, ARRANGED ACCORDING TO THEIR HOSTS. By ALBERT HASSALL. In the following compendium are included the hosts for all of the parasites discussed in this paper. The numbers of the hosts refer to the numbers in von Linstow's (1878) Compendium. In selecting the scientific names of hosts, I have been guided by the advice of Dr. T. S. Palmer, of the Biological Survey, TI. S. Department of Agriculture. B signifies that either Stiles or I have examined the parasite for the host in question in North America. n signifies that either Stiles or I have examined this parasite for the host in question, but the specimen was not North American. ? signifies that I doubt the validity of the determination or the validity of the species. t signifies that I reserve judgment upon the species. MAMMALS (Mammalia). PRIMATES. 1. Homo sapiens. Man. Dicrocoelium lanceatum, p. 55 Liver. Fasciola hepatica, p. 29 Liver. ? Fasciola hepatica angusta, p. 48 Lungs. ? Fasciola gigantica, p. 49 Lungs. E Schistosoma haematobium, p. 58 Veins. Bothriocephalus cordatus, p. 85 Intestine. B BotJtriocephalus latus, p. 85 4 Intestine. Botlmocephalm Mansoni, p. 85 Intestine. E Cysticercus cellulosae, p. 89 Muscles, eye, and brain. ? Cysticercus tenuicollis, p. 96 Omentum. Darainea madagascariensis, p. 86 Intestine. IMpi/lidium caninum, p. 86 Intestine. E Echinococcus polymorphic, p. 113 Especially liver and lungs. E Hymenolepis diminuta (including Taenia flavopunctata), p. 86 Intestine. D Hymenolepis murina (including Taenia nana), p. 86 Intestine. . . Erabbea grandis Intestine. Et Taenia confnsa,p.8o Intestine. E Taenia saginata, p. 71 Intestine. E Taenia solium, p. 89 Intestine. Simla faunus. Cysticercus tenuicollis, p. 96. 14. Simla inuus. (See Macacus inuus.) 9. Simla rubra. (See Cercopithecus patas.) 137 138 INSPECTION OF MEATS FOR ANIMAL PARASITES. 19. Simla silenus. (See Macacus silenus.) Semnopithecus entellus. Hanuman langur. Cysticei-cus tenuicollis, p. 96. 4. Cercopithecus cephus. Cysticercus cellulosae, p. 89 Peritoneum. 5. Cercopithecus cynosurus. Malbrouck Guenon. Cysticercus tenuicollin, p. 96 Liver and mesentery. 6. Cercopithecus fuliginosus. Sooty Monkey. Schistosoma haematoMum (Cobbold's Bilharzia mayna), p. 58 Veins. 7. Cercopithecus mona. Mona Guenon. Cysticercus tenuicollis, p. 96. 9. Cercopithecus patas. Patas Guenon. Cysticercus cellulosae, p. 89. 10. Cercopithecus sabaeus. Grivet Guenon. Cysticercus tenuicollis, p. 96 Liver and mesentery. 12. Macacus cynomolgus. Crab-eating Macaque. Cysticercus tenuicollis, p. 96 Liver and mesentery. Echinococcus polymorphus, p. 113 Viscera. 14. Macacus inuus. Barbary Macaque. Cysticercus cellulosae, p. 89 Peritoneum. Cysticercus tenuicollis, p. 96 Peritoneum. Echinococcus polymorphus, p. 113 Viscera. 19. Macacus silenus. Lion-tailed Macaque. Echinococcus polymorplius, p. 113 Viscera. 12. Inuus cynomolgus. (See Macacus cynomolgus.) 14. Inuus ecaudatus. (-See Macacus inuus.) 17. Papio maimoii. Mandril. Cysticercus tenuicoUis, p. 96 Liver and mesentery. 17. Cynocephalus maimon. (See Papio maimon.) CARNIVORES (Carnivora). 191. Ursus arctos. Brown Bear. Cysticercus cellulosae, p. 89 Muscles. 167. Vulpes lagopus. Arctic Fox. Taenia coenurus, p. 109 Intestine. 165. Cams familiaris. Dog. Bothriocephalus cordatus, p. 101 Intestine. Bothriocephalus fuscus, p. 101 Intestine. Bothriocephalus latus, p. 101 , Intestine. Bothriocephalus serratus, p. 101 Intestine. Cysticercus cellulosae, p. 89 Muscles and peritoneum. H Dipylidium canin um, p. 102 Intestine. D Mesocestoides lineatus, p. 102 Intestine. Taenia coenurus, p. 109 Intestine. S Taenia echinococcus, p. 114 Intestine. D Taenia Krabbei, p. 102 Intestine. H Taenia marginata, p. 96 Intestine. E Taenia serialis, p. 102 Intestine. EB Taenia serrata, p. 102 Intestine. 146. Felis domestica. Cat. ? Dicrocoelium lanceatum, p. 55 Gall bladder. Fasciola hepatica, p. 29. Cysticercus cellulosae, p. 89. Ci/sticercus tenuicollis, p. 96. Echinococcus polymorphus, p. 113. COMPENDIUM OF THE PARASITES. 139 RODENTS (Rodentia). Lepus californicus. Coenurus serialis, p. 102. Lepus callotis. H Coenurus serialis, p. 102. 137. Lepus cuniculus. European Wild Rabbit. Dicrocoelium lanceatum, p. 55. Fasciola hepatica, p. 29. D Coenurus serialis, p. 102. ? Coenurus cerebralis, p. 109. Echinococcus polymorpltus, p. 113. 137a. Lepus cuiiiculus domesticus. Common domesticated Rabbit. Fasciola hepatica, p. 29 Liver. ? Coenurus cerebralis, p. 109 Muscles. Coenurus serialis, p. 102 Muscles. 140. Lepus timidus. Common European Hare. Dicrocoelium lanceatum, p. 55 Gall bladder. Fasciola hepatica, p. 29 Liver. ? Coenurus cerebralis, p. 109 Muscles. Coenurus serialis, p. 102 Muscles. 139. Lepus variabilis. Mountain Hare. Dicrocoelium lanceatum, p. 55 Liver. Coenurus serialis, p. 102 Connective tissue. Cavia cobaya. Guinea Pig. Fasciola hepatica caviae, p. 48 Liver. 110. Mus rattus. Black Rat. Cysiicercus cellulosae, p. 89 Peritoneum. 98. Castor fiber. European Beaver. Fasciola hepatica, p. 29 Liver. 87. Sciurus cinereus. Cysticercus tenuicollis, p. 96 Liver and mesentery. 86. Sciurus vulgaris. European Squirrel. Fasciola hepatica, p. 29 Liver. Cysticercus tenuicollis, p. 96 Liver and mesentery. UNGULATES (Ungulata), 206. Elephas indicus. Indian Elephant. Fasciola hepatica, p. 29 Liver. 248. Equus caballus. Horse. D Fasciola hepatica, p. 29 Liver. Coenurus cerebralis, p. 109 Cerebrum. D Echinococcus polymorphus, p. 113 Liver. 246. Equus asinus. Ass. Dicrocoelium lanceatum, p. 55 Liver. D Fasciola hepatica, p. 29 Liver. n Echinococcus polymorphus, p. 113 Liver. 215, Bos bubalis. Indian Buffalo. Amphistoma cervi, p. 64 Rumen. D Fasciola liepatica aegyptiaca, p. 48 Liver. D Gastrotliylax gregarius, p. 67 Rumen. 217&. Bos frontalis. Gayal. Gastrothylax Cobboldii, p. 67 Rumen. Gastrothylax clongatum, p. 67 Rumen. Homalogaster Paloniae, p. 67 : Caecum. Bos indicus. Zebu. (See also p. 67). Moniezia espaiisa, p. 128 Intestine. 140 INSPECTION OF MEATS FOB ANIMAL PARASITES. 216. Bos taurus. Domesticated cattle. D AmpMstoma cervi, p. 64 Rumen. Amphistoma explanatum, p. 67 Gall bladder. AmpMstoma tuber culatnm, p. 67 Rumen. D Dicrocoelium lanceattim, p. 55 Liver. Dicrocoelium pancreaticum, p. 57 Pancreas. ? Fasciola yiyantica, p. 49 Liver. E Fasciola hepatica, p. 29 Liver and lungs. D .Fasciola hepatica angusta, p. 48 Liver. D Fasciola liepatica aegyptiaca, p. 48 Liver. E Fasciola magna, p. 49 Liver and lungs. Gastrothylax crumenifer, p. 67 Rumen. Homalogaster Poirieri, p. 67 Large intestine. D Schistosoma bovis, p. 60 Veins. ? Schistosoma liaematobium, p. 58 Veins. Coenurus cerebralis, p. 109 Brain. E Cysticercus foot-is, p. 71 Muscle. B Cysticercus tenuicollis, p. 96 Liver and mesentery. E Echinococcus polymorphus, p. 113 Li ver and lungs. D Moniezia alba, p. 127 Intestine. D Moniezia Benedeni, p. 128 Intestine. E Moniezia expansa, p. 128 Intestine. B Moniezia planissima, p. 127 Intestine. ? Stilesia centripunctata, p. 130 Intestine. ? Stilesia globipiinctata, p. 130 Intestine. ? Thysanonoma Giardi, p. 129 Intestine. 218. Ovibos moschatus. Musk Ox. Moniezia expansa, p. 128 Intestine. Ovis ammon. Echinococcus polymorphus, p. 113. 219. Ovis argali. Argali. Fasciola hepatica, p. 29 Liver. Cysticercus tenuicollis, p. 96 Liver and mesentery. Echinococcus polymorphus, p. 113 Liver and lungs. 220. Ovia aries. Domesticated sheep. E Amphistoma cervi, p. 64 Ruinen. D Dicrocoelium lanceatum, p. 55 Liver. E Fasciola hepatica, p. 29 Liver. Dicrocoelium pancreaticum, p. 57. Schistosoma bovis, p. 60 Veins. D Coenurus cerebralis, p. 109 Brain and spinal cord. E Cysticercus tenuicollis, p. 96 Mesentery. D Echinococcus polymorplius, p. 113 Liver and lungs. Moniezia alba, p. 127 Intestine. D Moniezia Benedeni, p. 128 Intestine. E Moniezia expansa, p. 128 Intestine. D Moniezia Neumanni, p. 128 Intestine. ! D Moniezia nullicollis, p. 26 Intestine. B Moniezia planissima, p. 127 Intestine. E Moniezia trigonophora, p. 128 Intestine. D Moniezia Vogti, p. 127 Intestine. D Stilesia centripunctata, p. 130 Intestine. D Stilesia globipunctata, p. 130 Intestine. B Thysanosoma actinioides, p. 128 Gall ducts and intestine. D Thysanosoma Giardi, p. 129 Intestine- COMPENDIUM OF THE PARASITES. 141 220. Ovis laticauda. D Mon iezia expansa, p. 128 Intestine 221. Ovis musimon. Mufflon. Coenurus cerelralis, p. 109 Cerebrum. Cysticercus tenuicollis, p. 96 Liver dkontrollens Standpunkt over for tintet Oksekod p. 33-83. REISSMAN. 1897. Referat [of Vollers, Noack, Zschokke, Foth, Glage] cattle from fluke disease 45 diagram showing season of danger from flukes 41 discussion of echinococcus hydatid.. 113-125. disease caused by fringed tapeworm . . . 128 from common liver fluke 34 from thin-necked bladder worm. ... 99 effects of common liver fluke 34 forms of Jfoniezia 127 frequency of lancet fluke 56 general precautions against fluke dis- ease 47 j gid bladder worm, discussion 108-112 hydatid disease 119 lancet fluke 55 lesions of bovine blood fluke 60 life history of adult tapeworm loO means of prevention of fluke disease. . . 46 parasitic worms 20 prevention of tapeworm disease 135 species of flukes 28 tendency to fatten from fluke disease . . 45 treatment and prevention of gid dis- ease Ill for tapeworm disease 133 of disease from flukes 44 fringed tapeworm 129 verminous diseases 15 Slaughterhouse care to prevent tapeworm infection .... 121, 125. 138.J disposal upon abandonment 15 raising of hogs in yards 15 sanitary supervision 14 steps for segregation 14 INDEX TO SUBJECTS. 161 55 42 Snails as -Page. t enemies of stock raisers 42 means of destroying, for prevention of fluke disease 47 source of infection with large American liver flcke tock raisers snails as enemies value of information regarding tape- worms 12 Suez, case of bilharziosis 61 Swine. (See alto Hogs.) adult tapeworms 126 discussion of echinococcus hydatid .. 113-125 Taenia marginata iu dogs, period of devel opment 104 Taeniidae, description ---- 85 discussion of family of tapeworms 68-136 Tapeworm disease caution in treatment 134 dogs 102 in cattle and sheep 131-136 man, decrease as result of inspec- tion of meats 11 sheep and cattle, prevention 135 1 1 Tapeworms adult, iu cattle and sheep 125 and flukes of cattle, sheep, andhogs.key. 21 differences of cysticercus and echiuococ- cus dogs fringed, cause of disease in sheep treatment of disease in sheep gid,-in dogs, discussion 108-112 hard shell, description and classifica- tion 70 life history 69 in cattle, sheep, and hogs, key 24 life history 130 man, adult and larval 94 ways of determining species 86 marginate, characters 96 of dogs, key 101 treatment of disease 106-108 5257 No. 19 11 79 123 128 129 Tapeworms- Continued. Page. methods for prevention in man 89 number and percentage of infection of dogs 105 of man, key 84 methods of preventing infection of cattle 83 of Taeniidae family, characters 68 or cestodes, discussion 68-130 order of flat worms, discussion 21 hogs 92 symptoms, diagnosis, and treatment of infection in man 87 of pork measles, in a pec t i on 92 time of development of cysticercus 73 transmissihility from animals to man .. t>8 unarmed distribution 84 Temperature necessary to destroy bladder worms 82 Texas outbreak of fluke disease 53 prevalence of fluke disease among cat- tle 4?, Thysanosoma, genus of tapeworms 128-130 Tonkin, disease from pancreatic fluke 57 Trematodes or flukes order of flat worms, discussion 21 technical discussion 27 Trichinous hogs, die interment and eating of carcasses buried by sanitary officials. 16 Turpentine, use against tapeworm 88 United States, frequency of hydatid dis- ease 122 Virchow on proportion of cysticercus in man 85 Water- care for prevention of tapeworm disease. 136 danger in districts infected with bil- harziosis 63 Wet years, effect on flukes in' animals 40 Wool, effect of tapeworm disease 128 Worms, parasitic, of cattle, sheep, and hogs. 20 Ziindel, division of periods of disease from common liver fluke 30