UNIVERSITY OF CALIFORNIA PUBLICATIONS 
 
 COLLEGE OF AGRICULTURE 
 
 AGRICULTURAL EXPERIMENT STATION 
 
 BERKELEY, CALIFORNIA 
 
 STUDIES ON A NUTRITIONAL DISEASE OF POULTRY 
 CAUSED DY VITAMIN A DEFICIENCY 
 
 BY 
 
 J. R. BEACH 
 
 BULLETIN No. 378 
 
 May, 1924 
 
 UNIVERSITY OF CALIFORNIA PRINTING OFFICE 
 
 BERKELEY, CALIFORNIA 
 
 1924 
 
Digitized by the Internet Archive 
 
 in 2012 with funding from 
 
 University of California, Davis Libraries 
 
 http://www.archive.org/details/studiesonnutriti378beac 
 
STUDIES ON A NUTRITIONAL DISEASE OF POULTRY 
 CAUSED BY VITAMIN A DEFICIENCY 
 
 By J. R. BEACHi 
 
 In 1919, Haring, Beach, and Jaffa 2 reported a study of several 
 outbreaks of a disease occurring in flocks of pullets in California, 
 which, so far as could be determined by a search of the literature, had 
 not been previously described. The symptoms resembled those of 
 "roup" more than of any other disease of fowls known to the writer, 
 but differed enough so that a differential diagnosis was readily made. 
 
 Owners of flocks in which the disease occurred reported losses of 
 about 10 per cent of their fowls within from two to six weeks. Exam- 
 ination of several such flocks showed that from 10 to 20 per cent of 
 the fowls had typical lesions. All flocks observed consisted of fowls 
 in their first laying year or of pullets that had not reached laying age. 
 
 Age of Fowls Affected. — The disease occurs more frequently in 
 fowls between the ages of four and twelve months than in those 
 younger or older. The explanation of the infrequency with which 
 younger birds are affected is that they usually receive an adequate 
 diet, and not that they are less susceptible. Older birds are appar- 
 ently quite resistant to the disease although it has been observed in 
 fowls more than two years old. 
 
 Time of Occurrence. — Outbreaks have been confined largely to 
 periods of the year when dry or cold conditions, or both, made it 
 difficult to raise green food. These periods comprise the late summer 
 and fall months before the first rainfall, and the winter months, 
 particularly January. 
 
 Symptoms and Lesions. — The characteristic symptoms of this 
 disease are confined to the head and involve the nasal passages, the 
 mouth, pharynx, and esophagus, and the eyes. 
 
 A discharge from the nostrils of a watery or viscid fluid is nearly 
 always present. Later this may collect in the infraorbital sinuses, 
 become transformed into a caseous mass and cause swelling of the 
 face. This involvement of nasal passages is indistinguishable from 
 the commonly occurring "colds and roup" and in the absence of 
 other symptoms is of no diagnostic value. 
 
 i Assistant Professor of Veterinary Science. 
 2 Calif. Agr. Exp. Sta. Ept. (1920), 79. 
 
4 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 
 
 The lesions in the mouth, pharynx, esophagus, and crop consist of 
 collections of white caseous material in the mucous glands (fig. 1). 
 On the surface of the mucous membrane they appear as circular white 
 pustule-like caseous patches, from 0.5 to 2 mm. in diameter. The 
 application of pressure around them forces out a slender cylindrical 
 caseous mass, 2 or 3 mm. in length. These lesions commonly appear 
 first in the pharynx and later on the tongue, on the floor of the 
 mouth, and in the esophagus. 
 
 The number of pustules may remain small or become so large 
 as to almost cover the mucous membrane surface. On autopsy, 
 pustules are frequently found in the esophagus throughout its entire 
 length. Unattached masses of white caseous material are often pres- 
 ent, particularly in the cleft palate, pharynx, and larynx. Pustules, 
 in very many cases, precede all other definite symptoms (figs. 2 and 3). 
 They have been found in nearly all affected fowls examined and, so 
 far as is known, are associated with no other disease or condition. 
 
 The lesions in the eye consist of an ophthalmia which produces 
 puffiness of the eyelids, reddening of the conjunctiva, a profuse watery 
 secretion which soon becomes viscid and may glue the eyelids together. 
 These symptoms are followed by the formation of a tightly adherent 
 white film over the membrana nictitans and the accumulation of a 
 mass of white caseous material within the conjunctival sacs (fig. 4). 
 The film over the membrana nictitans and the whiteness of the caseous 
 material are the characteristics of these eye lesions which differentiate 
 them from similar lesions due to other causes. Eye involvement has 
 been observed in less than 50 per cent of diseased fowls examined and, 
 as a rule, has been preceded or accompanied by the characteristic 
 pustules in the pharynx. 
 
 Marked emaciation and weakness (fig. 5) occur in the later stages 
 of the disease, although many fowls die suddenly while still in good 
 flesh. In many cases there is a deposit of a chalk-like substance on 
 the feathers below the vent. 
 
 Besides the lesions mentioned, the most prominent changes found 
 on autopsy are in the kidneys. These organs are usually pale and 
 marked by a network of fine white lines which are urate-filled tubules 
 (fig. 6). In some cases the kidneys are spotted with collections of 
 urates (fig. 7). Occasionally there is a deposit of urates on the heart, 
 pericardium, liver, omentum, and intestines. In some cases the 
 ureters are greatly distended with urates. 
 
 The bacteriological examination of diseased birds showed the 
 caseous material in the mouth and eyes to be swarming with several 
 types of rod-shaped bacteria which grew readily on ordinary culture 
 
BULLETIN 378] STUDIES ON A NUTRITIONAL DISEASE OF POULTRY 5 
 
 media. Attempts to produce the disease, however, in healthy birds 
 by inoculation with cultures or with the caseous material itself failed 
 in all cases. Confining healthy with diseased fowls in small coops 
 
 Fig. 1. — An advanced case of vitamin A deficiency, showing the pharynx 
 and esophagus studded with pustules. 
 
6 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 
 
 also gave negative results. No bacteria were found in smears nor 
 growth obtained in cultures made from the heart blood, liver, spleen, 
 and kidneys. 
 
 Results of Control Experiments. — When all attempts to transmit 
 the disease or to establish any etiological factors of an infectious 
 nature failed, incorrect feeding methods were suspected to be the 
 cause. Since in all flocks affected the supply of green food was very 
 scanty or entirely lacking, an insufficient amount of greens was the 
 first dietary factor suspected. The nature of the kidney lesions sug- 
 gested too much protein and the appearance of typical lesions in fowls 
 confined in cages and fed only whole grain suggested too little protein 
 as possible causes. In all field outbreaks, however, the amount of 
 protein in the rations was not deficient. The report of one owner 
 that the disease had appeared a short time after the introduction of 
 coconut-meal into the ration brought this food stuff under suspicion. 
 It was, therefore, suggested to owners of affected flocks that the 
 disease might be controlled by increasing the amount of green food, 
 decreasing the percentage of protein, and entirely eliminating the 
 coconut-meal from the ration. 
 
 The following reports of observations made in four flocks are 
 given as illustrations of the results obtained by the adoption of these 
 suggestions : 
 
 Flock No. 1 — Contained 702 hens, 15 months old, 115 or 16.3 per 
 cent of which were diseased. Seventy-five birds had died within two 
 weeks. Very little green food had been given for five weeks. Within 
 thirty days after the ration was changed and the greens increased, 
 the disease had entirely disappeared with a loss of but twenty 
 additional birds. 
 
 Flock No. 2 — Contained 784 pullets, about 4 months old. Fifty- 
 nine or 7.5 per cent were diseased. No greens had been fed for a 
 month. About one hundred had died during this period. Greens 
 were fed liberally and the flock entirely recovered in thirty days with 
 a mortality of but nineteen additional birds. 
 
 Flock No. 3— Consisted of 1336 hens, 15 months old, 239, or 17.8 
 per cent of which had characteristic lesions. These birds had free 
 access to growing corn a short distance from their house, but few of 
 them were getting it. About one hundred and fifty had died within 
 six weeks. Greens were fed to the flock in the yards and within two 
 weeks the number of diseased was reduced to forty. The additional 
 loss from death was but eighteen fowls. 
 
 Flock No. 4 — Consisted of approximately 700 pullets, about 4 
 months old. Detailed examination was not made of this flock but 
 at least 10 per cent were visibly sick. Examination of several indi- 
 
BULLETIN 378] STUDIES ON A NUTRITIONAL DISEASE OF POULTRY 7 
 
 viduals revealed the characteristic lesions. The owner stated that 
 he was feeding all the greens that it was possible for him to obtain. 
 He was then advised to feed the greens in small amounts widely scat- 
 tered three times each day instead of feeding the total daily supply 
 at one time in a trough. It was thought that this change in the feed- 
 ing method, by permitting each fowl to get a more nearly equal share 
 and eliminating all waste, might result in better utilization of the 
 scanty supply of greens. Within a week the flock showed marked 
 improvement and no further losses occurred. 
 
 " ■ JBr¥ 
 
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 Fig. 2. — The appearance of a few pustules in the pharynx is often the first 
 indication of vitamin A deficiency in fowls. 
 
 The success in controlling outbreaks so strengthened the theory 
 that the disease is caused by nutritional factors, that additional 
 investigation seemed warranted. Accordingly a controlled feeding 
 experiment designed to furnish evidence concerning all suspected 
 feeding errors, i.e., a deficiency of green food, an excess of protein 
 and coconut-meal, a deficiency of protein, was carried out during 
 1920-21 and briefly reported on in the Report of the California Agri- 
 cultural Experiment Station and other publications. 2 
 
 sBeach, J. E., A nutritional disease resembling roup. Calif. Agr. Exp. Sta. 
 Eep., 1920-21, 140. 
 
 Differential diagnosis of diseases of the head of fowls. Poultry Science, 1, 1-8 
 (1921). 
 
 Progress in combatting poultry disease in the United States. Trans, of the 
 First World's Poultry Congress, 1, 213-235 (1921). 
 
UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 
 
 EXPERIMENT No. I— PART 1 
 
 In this experiment, eight pens of eighteen pullets each, six months 
 old, were used. These were divided into four groups of two pens each. 
 A different mash mixture, fed dry in hoppers, was given to each group. 
 One pen of each group was fed all the green food (alfalfa and green 
 barley) they would eat without waste, and the other pen was fed 
 none. The same grain mixture, consisting of barley, 50 per cent; 
 coarse cracked yellow corn, 25 per cent ; and milo maize, 25 per cent, 
 was given to all pens. The experiment was started February 19, 
 1920, and continued until February 8, 1921. Each fowl was carefully 
 examined at from seven to fourteen-day intervals. 
 
 Group I (pens 32a and 38a) was fed the following mash mixture: 
 
 Wheat Bran 50 lbs. 
 
 Wheat Shorts 50 lbs. 
 
 Ground Barley 50 lbs. 
 
 Meat Scrap 10 lbs. 
 
 Fish Scrap 10 lbs. 
 
 Soya Bean Meal 20 lbs. 
 
 This mixture was believed to furnish a proper percentage of 
 protein and contained no coconut-meal. Greens were fed to pen 32a 
 but not to 38a. 
 
 No birds in 32a became affected with the nutritional disease. 
 Three died from other causes. 
 
 One bird in pen 38a died from another cause fourteen days after 
 the experiment was begun. All of the seventeen remaining developed 
 typical lesions. The first lesion was observed on the forty-third day 
 and all were affected by the one hundred and fourth day. Pustules 
 alone occurred in sixteen of these and both pustules and eye lesions 
 in one. Five recovered and twelve died. Characteristic kidney 
 changes were found in all. Cultures and smears from the heart and 
 liver of nine were negative. 
 
 Group II (pens 32b and 38b) was fed a mash mixture consisting of 
 
 Wheat Bran 50 lbs. 
 
 Wheat Shorts 50 lbs. 
 
 Ground Barley 50 lbs. 
 
 Meat Scrap 10 lbs. 
 
 Fish Scrap 10 lbs. 
 
 Coconut-meal 40 lbs. 
 
 This mixture was believed to provide a suitable amount of protein 
 and also contained coconut-meal. Pen 32b received greens and 38b 
 received none. 
 
BULLETIN 378] STUDIES ON A NUTRITIONAL DISEASE OF POULTRY 9 
 
 One bird in 32b developed ophthalmia and died on the fifty-first 
 day. Characteristic kidney lesions were found on autopsy. This 
 fowl had a severe cold when the experiment started, which soon 
 resulted in such marked swelling' of both infraorbital sinuses that the 
 eyelids were nearly closed. This condition seriously interfered with 
 the consumption of food and possibly therefore was responsible for 
 the occurrence of the nutritional disease lesions. One fowl died from 
 a severe intestinal worm infestation. All others in this pen remained 
 healthy. 
 
 Fig. 3. — Although outwardly this fowl appears in perfect health, the char- 
 acteristic pustules of vitamin A deficiency are present in the pharynx. 
 
 All of the eighteen birds in pen 38b became affected with the 
 nutritional disease. The first lesions were found on the forty-second 
 day and all birds had exhibited lesions by the one hundred and twenty- 
 first day. Seventeen exhibited pustules only and one both pustules 
 and ophthalmia. Eight recovered and ten died. One of the ten dead 
 was not autopsied but typical kidney changes were found in nine. 
 Smears and cultures from the heart and liver of these were negative. 
 
 Group III (pens 33a and 39a) was fed the same mash mixture as 
 Group II with the exception that it contained 50 per cent more coco- 
 nut-meal. This was believed to furnish an excessive amount of both 
 protein and coconut-meal. Greens were fed in 33a but not in 39a. 
 
10 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 
 
 A few pustules were observed in the pharynx of one bird in pen 
 33a when the experiment was begun. Two others exhibited a few 
 pustules on the seventeenth day. The lesions had disappeared from 
 all three on the thirty-seventh day and the fowls remained healthy. 
 No other fowls became affected. Four died from other causes. 
 
 In pen 39a two fowls died during" the first month from intestinal 
 parasites. The remaining sixteen became affected with the nutritional 
 disease. The first case was observed on the forty-third day. Twelve 
 had pustules alone and four both pustules and ophthalmia. Seven 
 recovered and nine died. Typical kidney changes were found in all 
 of these. Smears and cultures made from the hearts and livers of 
 these were negative. 
 
 Group IV (pens 33b and 39b) was fed no mash. This was con- 
 sidered to provide a ration with less than the normal amount of 
 protein for laying hens. Greens were fed in 33b, but not in 39b. 
 
 None of the birds in 33b became affected with the nutritional 
 disease. Three died from other causes. 
 
 Four fowls in 39b died from ruptured yolk. Bad. avisepticum 
 was isolated from three of them. One other fowl suffered a prolapse 
 of the uterus and was killed by its mates. One died from pulmonary 
 hemorrhage. The twelve remaining all developed typical pustules. 
 Three recovered and nine died. The characteristic kidney changes 
 were found in all the dead. Smears and cultures made from the hearts 
 and livers were negative. 
 
 A tabulated summary of results is given in table I. 
 
 Discussion of the Experiment. — With the exception of nine birds 
 which died from other causes, all of the seventj'-two birds in the 
 pens in which no green food was fed developed the characteristic 
 pustules in the mouth and pharynx or ophthalmia. Sixty-two per 
 cent of these died. Nearly all the deaths occurred within the first four 
 months. Most of the fowls that survived this period appeared to have 
 developed a tolerance for the ration deficient in green food. In a 
 few fowls that recovered the lesions were recurrent. 
 
 In the pens in which greens were fed, there were but four birds 
 which at any time exhibited any nutritional disease symptoms and 
 but one that died. One of these had the lesions when the experiment 
 was started and two others developed during the first month a very 
 few pustules which remained but a few days. The general health 
 of these at no time appeared to be impaired. The occurrence of the 
 nutritional- disease lesions in the one fowl that died was probably 
 influenced by a swelling of the infraorbital sinuses which caused a 
 partial closure of the eyes and thus interfered with food consumption. 
 
BULLETIN 378] STUDIES ON A NUTRITIONAL DISEASE OF POULTRY 
 
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12 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 
 
 Since the affected birds were uniformly distributed throughout 
 the pens in which no greens were fed, irrespective of the rest of the 
 ration, and the number affected was so small as to be almost negligible 
 in the pens in which greens were fed, it appeared quite certain that 
 a lack of greens was the sole cause of the occurrence of nutritional 
 disease among the fowls used in this experiment. 
 
 
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 Fig. 4. — The characteristic ophthalmia of vitamin A deficiency. 
 
 EXPERIMENT No. I— PART 2 
 
 This was undertaken to further demonstrate a deficiency of green 
 food in the ration as the etiological factor of this nutritional disease. 
 From March 10, 1921, one month after the preceding experiment was 
 terminated, until August 28, 1921, greens were withheld from pens 
 32a, 32b, 33a, and 33b, all of which had previously received greens, 
 and fed to pens 38a, 38b, 39a and 39b, which had previously received 
 no greens. The rations were otherwise unchanged. The results were 
 as follows: 
 
 Pen 32a, fifteen fowls. Nine developed pustules. One of these 
 also had ophthalmia. One died and eight recovered. The first case 
 was found on May 13, the sixty-third day of the experiment. No new 
 cases appeared after July 6. 
 
BULLETIN 378] STUDIES ON A NUTRITIONAL DISEASE OF POULTRY 13 
 
 Pen 32b, fifteen fowls. Ten developed pustules. None had 
 ophthalmia. Three died and seven recovered. The first case appeared 
 on May 21, the seventy-third day of the experiment. No new cases 
 appeared after July 6. 
 
 Pen 33a, thirteen fowls. Ten developed pustules. Two had 
 ophthalmia in addition. Four of these died and six recovered. The 
 first case was observed on June 14, the ninety-fourth day of the 
 experiment. No new cases appeared after July 6. 
 
 Fig. 5. — Typical appearance of fowls with the disease caused by vitamin A 
 
 deficiency. 
 
 Pen 33b, fourteen fowls. Pustules appeared in only one fowl. 
 This bird recovered. 
 
 In pens 38a, 38b, 39a, and 39b no cases of nutritional disease 
 appeared after the feeding of greens was begun. 
 
 Summary: Thirty of the fifty-seven birds in the four pens in which 
 no greens were fed became affected with nutritional disease lesions. 
 Eight of the thirty died, the remainder having but mild lesions which 
 soon disappeared. Ophthalmia was observed in but three birds, the 
 lesions in all others being confined to pustules. The lesions were 
 slower in appearing, milder in character, and the percentage of birds 
 affected much smaller than in the preceding portion of the experi- 
 ment. This was thought to be due very probably to the increased age 
 of the birds when the second portion of the experiment was carried out. 
 
14 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 
 
 No evidence of nutritional disease was observed in any of the pens 
 in which greens were fed. 
 
 These results confirmed and strengthened the inference drawn 
 from the results of the first portion of the experiment and completed 
 the demonstration that a deficiency of green food in the ration was 
 the sole causative factor of the occurrence of nutritional disease among 
 the birds used in this experiment. 
 
 It seems quite probable, however, that green food did not prevent 
 the disease merely because it was green and succulent, but because it 
 furnished some dietary essential which was lacking in the other in- 
 gredients of the rations. Otherwise this nutritional disease of poultry 
 presumably would be very prevalent instead of being practically un- 
 known in the middle western and eastern states during winter months, 
 when many flocks received very little or no green food. It was there- 
 fore suspected that the real cause of the disease is a vitamin or mineral 
 deficiency, and investigation of this point was undertaken on April 
 18, 1923. 
 
 EXPERIMENT No. II 
 
 The general plan of this experiment was to feed fowls a suitable 
 mash and grain mixture as a basal ration and to supplement this with 
 known good sources of vitamines A, B, and C or a salts mixture, 
 butter-milk, or green food. 
 
 The basal ration used during the first two and one-half months 
 was a mash consisting of : 
 
 Wheat Bran 25 parts 
 
 Wheat Shorts 25 parts 
 
 Yellow Corn Meal - 25 parts 
 
 Soya Bean Meal : 10 parts 
 
 Meat Scrap 15 parts 
 
 and a commercial ' ' chick grain ' ' mixture composed of 
 
 Cracked Milo 6 parts 
 
 Cracked White Egyptian Corn 4 parts 
 
 Cracked Wheat 12 parts 
 
 Cracked Yellow Corn 4 parts 
 
 Cracked Rice 1 part 
 
 Steel Cut Oats 2 parts 
 
 Ground Bone 1 part 
 
 It was, of course, recognized that this ration supplied some vitamin 
 A in the yellow corn, and vitamin B in all of the grains. However, 
 it does not differ essentially from rations fed to flocks in which the 
 
Bulletin 378] STUDIES ON A NUTRITIONAL DISEASE OF POULTRY 
 
 15 
 
 disease had occurred. This was considered to indicate that, although 
 these vitamins were present, the amounts were deficient. 
 
 On August 1 it was thought desirable to eliminate yellow corn 
 from the ration, so as to make it more nearly vitamin A free, and 
 
 Fig. 6. — Kidneys of a fowl injured by vitamin A deficiency. 
 
16 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 
 
 therefore ground barley was substituted for the yellow cornmeal in 
 the mash and the grain ration changed to equal parts of wheat, barley, 
 and white Egyptian corn. The mash was fed dry in hoppers and 
 the grain twice daily in the litter. 
 
 Vitamin A was supplied by cod-liver oil, 1 cc. of which was given 
 daily with a pipette to each bird. 
 
 Five per cent of dried yeast was added to the mash to supply 
 Vitamin B. 
 
 One cc. of orange juice was given to each bird daily to supply 
 Vitamin C. 
 
 The salts mixture contained: 
 
 Calcium Carbonate 30 parts 
 
 Calcium Phosphate 20 parts 
 
 Sodium Chloride 20 parts 
 
 Sodium Sulphate 15 parts 
 
 Iron Sulphate 15 parts 
 
 Two per cent of this was added to the mash. 
 
 The buttermilk was termed "family grade" by the creamery sup- 
 plying it. This was constantly before the birds in place of water. 
 The green food was blue grass and clover lawn clippings. Granite 
 grit was available at all times. The birds were confined in houses 
 with tight board floors and shavings litter. 
 
 The birds were three-month-old White Leghorns. They were 
 divided into eleven pens of fifteen birds each, and treated as follows: 
 
 Pen No. 1 — Basal ration only (control). 
 
 Pen No. 2 — Basal ration plus salts mixture. 
 
 Pen No. 3 — Basal ration plus cod-liver oil. 
 
 Pen No. 4 — Basal ration plus yeast. 
 
 Pen No. 5 — Basal ration plus orange juice. 
 
 Pen No. 6 — Basal ration plus cod-liver oil and yeast. 
 
 Pen No. 7 — Basal ration plus cod-liver oil and orange juice. 
 
 Pen No. 8 — Basal ration plus yeast and orange juice. 
 
 Pen No. 9 — Basal ration plus cod-liver oil, yeast, and orange juice. 
 
 Pen No. 10 — Basal ration plus buttermilk. 
 
 Pen No. 11 — Basal ration plus lawn clippings. 
 
 With one exception, no characteristic lesions appeared until 
 August 1, three and one-half months after the experiment was started, 
 when ten cases were found scattered through Pens 1, 2, 4, 5 and 8. 
 The confinement of these cases to those pens in which neither cod-liver 
 oil nor greens were fed seemed to point toward Vitamin A deficiency. 
 This, together with the fact that about twice as much time was 
 required for the appearance of lesions as in the preceding experiment, 
 
Bulletin 378] STUDIES ON A NUTRITIONAL DISEASE OF POULTRY 17 
 
 Fig. 7. — Kidneys spotted with urates due to vitamin A deficiency. 
 
18 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 
 
 made it seem possible that the yellow corn in the ration was supplying 
 enough Vitamin A to partly protect the fowls. For this reason the 
 changes in the basal ration already noted were made on August I. 
 
 The final results obtained in the different pens were : 
 
 Pen 1 — Basal ration only (control). Two fowls with typical 
 lesions were found on August 1 — the one hundred and fifth day. One 
 had from five to ten pustules in the pharynx and the other a slight 
 affection of both eyes. One fowl died on September 19 from rupture 
 of the vent. The fourteen remaining were either sick with, or dead 
 from, nutritional disease by September 14, the one hundred and forty- 
 ninth day. All were dead by October 3, the one hundred and sixty- 
 eighth day. In two that showed typical urate kidneys on autopsy, 
 a nasal discharge was the only ante-mortem symptom, and in one, 
 emaciation. Mouth lesions alone occurred in four cases, both pustules 
 and ophthalmia in five cases, and ophthalmia alone in two cases. All 
 had a discharge from the nostrils and two had distention of both infra- 
 orbital sinuses. 
 
 Pen 2 — Basal ration plus salts mixture. One bird died on July 5 
 from chronic coecidiosis. The kidneys appeared slightly more pale 
 than is normal, but could not be considered as typical of nutritional 
 disease. On August 1, the one hundred and fifth day, definite pustules 
 were found in one. "By x\.ugust 29, the one hundred and thirty-third 
 day, all of the remaining fourteen birds had become sick and three had 
 died. All were dead from nutritional disease by September 29, the one 
 hundred and sixty-fourth day. In one of the dead the only ante- 
 mortem symptom was emaciation, but typical "urate" kidneys were 
 found on autopsy. In five cases pustules only were found, in seven 
 cases both pustules and ophthalmia, and in one case ophthalmia only. 
 Kidney changes typical of nutritional disease were found in all. All 
 had a nasal discharge and in four there was distention of the infra- 
 orbital sinuses. 
 
 Pen 3 — Basal ration plus cod-liver oil. Except for a nasal dis- 
 charge which was present in twelve fowls some time during the experi- 
 ment, all birds remained healthy until October 10, when the experi- 
 ment was terminated. 
 
 Pen 4 — Basal ration plus yeast. One bird died suddenly on May 
 21. Autopsy revealed the kidneys filled with urates and a deposit 
 of urates on the surface of heart, pericardium and all of the abdominal 
 organs.- -It -was thought that this condition might have resulted from 
 yeast feeding rather than from nutritional disease. A second bird 
 that died on June 29 exhibited similar lesions. Death was attributed 
 
Bulletin 378] STUDIES ON A NUTRITIONAL DISEASE OP POULTRY 19 
 
 to the same cause. The third fatality occurred on June 3. Marked 
 emaciation from an undetermined cause was the only abnormality 
 found. 
 
 The first definite indications of nutritional disease were observed 
 on July 20, the ninety-third day, when typical pustules and ophthal- 
 mia of both eyes were found in one bird. This fowl quickly became 
 extremely emaciated and died on July 31, the one hundred and fourth 
 day. Spotted urate kidneys were found on autopsy. The disease 
 progressed with such rapidity in this pen that all had sickened and 
 six more had died by August 29, the one hundred and thirty-third 
 day. All were dead by September 21, the one hundred and fifty-sixth 
 day. Five cases exhibited pustules only and seven both pustules and 
 ophthalmia. Typical urate kidneys were found in all and a deposit 
 of urates on the surface of the abdominal organs in one of these. 
 A nasal discharge was present in all and distention of the infraorbital 
 sinuses in four. 
 
 Pen 5 — Basal ration plus orange juice. One bird died from an 
 undetermined cause on May 31. The first evidence of nutritional 
 disease was a slight ophthalmia in one bird on August 1, the one 
 hundred and fifth day. All of the fourteen remaining had become 
 sick and two had died by September 7, the one hundred and forty- 
 second day. All except two, which were discovered to be eating eggs, 
 were dead by October 3, the one hundred and sixty-eighth day. There 
 were seven cases with pustules alone and seven with both pustules and 
 ophthalmia. Nasal discharge occurred in all. Typical urate kidneys 
 were found in all that died. 
 
 Pen 6 — Basal ration plus cod-liver oil and yeast. One bird died 
 from chronic coccidiosis. A nasal discharge w T as present for a short 
 time in one. Otherwise, all birds in this pen remained healthy until 
 the termination of the experiment on October 10. 
 
 Pen 7 — Basal ration plus cod-liver oil and orange juice. Three 
 deaths occurred in this pen, one from heat stroke, one from chronic 
 coccidiosis, and one from strangulation. Eight birds had a nasal 
 discharge of short duration. No other evidence of disease of any kind 
 appeared. 
 
 Pen 8 — Basal ration plus yeast and orange juice. One bird died 
 on July 21 from chronic coccidiosis. On August 1, the one hundred 
 and fifth day, five fowls showed definite symptoms of nutritional 
 disease. Three had pustules only and two both pustules and ophthal- 
 mia. All had sickened and six had died b}^ August 29, the one hundred 
 and thirty-third day. All had died by September 24, the one hun- 
 
20 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 
 
 dred and fifty-ninth day. There were five cases of pustules alone, 
 seven of pustules and ophthalmia, and two of ophthalmia alone. A 
 nasal discharge was present in all and distention of the infraorbital 
 sinuses of one. Autopsy showed typical urate kidneys in all cases. 
 
 Pen 9 — Basal ration plus cod-liver oil, yeast and orange juice. 
 
 Three deaths occurred in the pen, one from chronic coecidiosis, 
 one from ruptured yolk, and one from leukemia. Nine of the fowls 
 had a nasal discharge some time during the experiment. Aside from 
 the preceding, the birds all remained healthy. 
 
 Pen 10 — Basal ration plus buttermilk. The first death occurred 
 on May 15 from an undetermined cause. Symptoms of nutritional 
 disease were observed in two fowls on August 13, the one hundred and 
 seventeenth day. Eight other fowls subsequently developed lesions, 
 making a total of ten cases. Two of these died. The remainder still 
 had lesions but were otherwise apparently healthy when the experi- 
 ment was terminated on October 10. Two fowls which had exhibited 
 no symptoms died. Typical urate kidneys were found in both and 
 urate deposits on the heart and abdominal organs of one. Two fowls 
 remained healthy throughout. 
 
 Pen 11 — Basal ration plus lawn clippings. Seven fowls had a 
 nasal discharge of short duration some time during the experiment 
 but otherwise all remained healthy. 
 
 A tabulated summary of the experiment is given in table 2. 
 
 Discussion of the Experiment. — With the exception of seven birds 
 which died from other causes, all of the seventy-five birds in the five 
 pens in which the basal ration was fed alone or supplemented by the 
 salts mixture, yeast, orange juice, or yeast and orange juice, developed 
 characteristic pustules in the mouth and pharynx, ophthalmia, or 
 kidney lesions. Sixty-six of these died and two were living at the 
 termination of the experiment, although pustules were still present 
 in both. These two fowls were found to be eating eggs, which very 
 possibly supplied sufficient Vitamin A to prevent death. 
 
 In the one pen in which buttermilk was fed, nutritional disease 
 affected twelve birds, only four of which died. Analyses of several 
 samples of the buttermilk showed a butterfat content of from 0.1 to 
 0.5 per cent. This very probably supplied sufficient Vitamin A to 
 modify the disease in this pen. 
 
 The lesions in the eighty birds affected were distributed as follows : 
 thirty-five, or 43.75 per cent, had pustules only ; fourteen, or 17.50 
 per cent, had ophthalmia only; twenty-five, or 31.25 per cent, had 
 
Bulletin 378] STUDIES ON A NUTRITIONAL DISEASE OF POULTRY 
 
 21 
 
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22 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION 
 
 both pustules and ophthalmia; and six, or 7.50 per cent, had kidney 
 lesions only. Definite kidney lesions were found in all on autopsy. 
 
 On the other hand, all of the seventy-five birds in the five pens in 
 which the basal ration was supplemented by cod-liver oil, cod-liver oil 
 and yeast, cod-liver oil and orange juice, cod-liver oil, yeast and 
 orange juice, or lawn clippings remained entirely free from all the 
 symptoms and lesions which characterize the nutritional disease. 
 
 Conclusions. — These results should justify the conclusion that the 
 disease is due to Vitamin A deficiency. 
 
 The possibility that it is Vitamin D rather than Vitamin A in the 
 cod-liver oil that prevents the development of this disease would seem 
 to be controverted by the following : 
 
 First. — The similarity of the ophthalmia to that occurring in rats 
 fed a ration deficient in vitamin A and the total lack of any symptom 
 of rickets suggestive of vitamin D deficiency. 
 
 Second — Green food proved as effective as cod-liver oil while the 
 results of experiments of Hughes 3 showed that green food would 
 not prevent development of symptoms of rickets. 
 
 Third. — Exposure of the fowls to an abundance of direct sunlight 
 through the open front of the houses did not prevent the development 
 of this disease, although Hughes' 3 found that a short daily exposure to 
 direct sunlight would prevent rickets. 
 
 Vitamin A deficiency as the cause might also explain the apparent 
 infrequent occurrence of this disease during winter months in middle 
 western and eastern states where yellow corn in poultry rations is 
 more extensively used than in California. 
 
 It would seem, therefore, that this disease which the writer has 
 previously designated as a nutritional disease resembling roup should 
 now be designated a nutritional disease caused by vitamine A de- 
 ficiency, although the name nutritional roup might be more suitable 
 for use by poultrymen. 
 
 There is little likelihood of this disease ever occurring in any flock 
 plentifully supplied with green food no matter how deficient in 
 sources of vitamin A the ration may otherwise be. In time of scarcity 
 of green food, the division of the available daily supply into several 
 feedings of small amounts and the liberal use of yellow corn and 
 buttermilk in the ration would in all probability at least partly com- 
 pensate for the deficiency. 
 
 3 Science, n.s., 59, 21. 1924. 
 
STATION PUBLICATIONS AVAILABLE FOR FREE DISTRIBUTION 
 
 No. 
 258. 
 
 261. 
 
 262. 
 
 263. 
 268. 
 273. 
 
 275. 
 
 276. 
 277. 
 278. 
 279. 
 280. 
 
 283. 
 285. 
 286. 
 287. 
 294. 
 298. 
 804. 
 
 312. 
 317. 
 
 319. 
 321. 
 324. 
 
 325. 
 
 328. 
 331. 
 S34. 
 
 335. 
 
 336. 
 
 339. 
 
 343. 
 344. 
 
 Irrigation and Soil Conditions in the 
 Sierra Nevada Foothills, California. 
 
 Melaxuma of the Walnut, "Juglans 
 regia." 
 
 Citrus Diseases of Florida and Cuba 
 Compared with those of California. 
 
 Size Grades for Ripe Olives. 
 
 Growing and Grafting Olive Seedlings. 
 
 Preliminary Report on Kearney Vine- 
 yard Experimental Drain. 
 
 The Cultivation of Belladonna in Cali- 
 fornia. 
 
 The Pomegranate. 
 
 Sudan Grass. 
 
 Grain Sorghums. 
 
 Irrigation of Rice in California. 
 
 Irrigation of Alfalfa in the Sacramento 
 Valley. 
 
 The Olive Insects of California. 
 
 The Milk Goat in California. 
 
 Commercial Fertilizers. 
 
 Vinegar from Waste Fruits. 
 
 Bean Culture in California. 
 
 Seedless Raisin Grapes. 
 
 A Study of the Effects of Freezes on 
 Citrus in California. 
 
 Mariout Barley. 
 
 Selections of Stocks in Citrus Propa- 
 gation. 
 
 Caprifigs and Caprification. 
 
 Commercial Production of Grape Syrup. 
 
 Storage of Perishable Fruit at Freezing 
 Temperatures. 
 
 Rice Irrigation Measurements and Ex- 
 periments in Sacramento Valley, 
 1914-1919. 
 
 Prune Growing in California. 
 
 Phylloxera-Resistant Stocks. 
 
 Preliminary Volume Tables for Second- 
 Growth Redwood. 
 
 Cocoanut Meal as a Feed for Dairy 
 Cows and Other Livestock. 
 
 The Preparation of Nicotine Dust as 
 an Insecticide. 
 
 The Relative Cost of Making Logs from 
 Small and Large Timber. 
 
 Cheese Pests and Their Control. 
 
 Cold Storage as an Aid to the Market- 
 ing of Plums. 
 
 BULLETINS 
 
 No. 
 
 346. 
 
 347. 
 
 348. 
 349. 
 
 350. 
 351. 
 352. 
 
 353. 
 354. 
 355. 
 357. 
 
 358. 
 
 359. 
 360. 
 
 361. 
 
 862. 
 363. 
 
 364. 
 
 366. 
 
 367. 
 
 369. 
 370. 
 371. 
 
 372. 
 
 373. 
 374. 
 
 375. 
 376. 
 
 Almond Pollination. 
 
 The Control of Red Spiders in Decidu- 
 ous Orchards. 
 
 Pruning Young Olive Trees. 
 
 A Study of Sidedraft and Tractor 
 Hitches. 
 
 Agriculture in Out-over Redwood Lands. 
 
 California State Dairy Cow Competition. 
 
 Further Experiments in Plum Pollina- 
 tion. 
 
 Bovine Infectious Abortion. 
 
 Results of Rice Experiments in 1922. 
 
 The Peach Twig Borer. 
 
 A Self-mixing Dusting Machine for 
 Applying Dry Insecticides and 
 Fungicides. 
 
 Black Measles, Water Berries, and 
 Related Vine Troubles. 
 
 Fruit Beverage Investigations. 
 
 Gum Diseases of Citrus Trees in Cali- 
 fornia. 
 
 Preliminary Yield Tables for Second 
 Growth Redwood. 
 
 Dust and the Tractor Engine. 
 
 The Pruning of Citrus Trees in Cali- 
 fornia. 
 
 Fungicidal Dusts for the Control of 
 Bunt. 
 
 Turkish Tobacco Culture, Curing and 
 Marketing. 
 
 Methods of Harvesting and Irrigation 
 in Relation to Mouldy Walnuts. 
 
 Bacterial Decomposition of Olives dur- 
 ing Pickling. 
 
 Comparison of Woods for Butter Boxes 
 
 Browning of Yellow Newtown Apples. 
 
 The Relative Cost of Yarding Small 
 and Large Timber. 
 
 The Cost of Producing Market Milk and 
 Butterfat on 246 California Dairies. 
 
 Pear Pollination. 
 
 A Survey of Orchard Practices in the 
 Citrus Industry of Southern Cali- 
 fornia. 
 
 Results of Rice Experiments at Cor- 
 tena, 1923. 
 
 Sun-Drying and Dehydration of Wal- 
 nuts. 
 
 CIRCULARS 
 
 No. No. 
 70. Observations on the Status of Corn 161. 
 Growing in California. 164. 
 87. Alfalfa. 165. 
 111. The Use of Lime and Gypsum on Cali- 
 fornia Soils. 166. 
 118. Correspondence Courses in Agriculture. 167. 
 117. The Selection and Cost of a Small 170. 
 
 Pumping Plant. 
 
 136. Melilotus tndica as a Green-Manure 172. 
 
 Crop for California. 173. 
 127. House Fumigation. 
 
 129. The Control of Citrus Insects. 174. 
 
 144. Qidium or Powdery Mildew of the Vine. 178. 
 
 151. Feeding and Management of Hogs. 179. 
 
 152. Some Observations on the Bulk Hand- 
 
 ling of Grain in California. 184. 
 
 158. Announcement of the California State 190. 
 
 Dairy Cow Competition, 1916-18. 193. 
 
 154. Irrigation Practice in Growing Small 198. 
 
 Fruit in California. 199. 
 
 155. Bovine Tuberculosis. 201. 
 
 157. Control of the Pear Scab. 202. 
 
 158. Home and Farm Canning. 
 
 160. Lettuce Growing in California. 203. 
 
 Potatoes in California. 
 
 Small Fruit Culture in California. 
 
 Fundamentals of Sugar Beet Culture 
 
 under California Conditions. 
 The County Farm Bureau. 
 Feeding Stuffs of Minor Importance. 
 Fertilizing California Soils for the 1918 
 
 Crop. 
 Wheat Culture. 
 The Construction of the Wood-Hoop 
 
 Silo. 
 Farm Drainage Methods. 
 The Packing of Apples in California. 
 Factors of Importance in Producing 
 
 Milk of Low Bacterial Count. 
 A Flock of Sheep on the Farm. 
 Agriculture Clubs in California. 
 A Study of Farm Labor in California. 
 Syrup from Sweet Sorghum. 
 Onion Growing in California. 
 Helpful Hints to Hog Raisers. 
 County Organizations for Rural Fire 
 
 Control. 
 Peat as a Manure Substitute. 
 
CIRCULARS — Continued 
 
 No. 
 
 205. Blackleg. 
 
 206. Jack Cheese. 
 
 208. Summary of the Annual Reports of the 
 
 Farm Advisors of California. 
 
 209. The Function of the Farm Bureau. 
 
 210. Suggestions to the Settler in California. 
 212. Salvaging Rain-Damaged Prunes. 
 
 214. Seed Treatment for the Prevention of 
 
 Cereal Smuts. 
 
 215. Feeding Dairy Cows in California. 
 217. Methods for Marketing Vegetables in 
 
 California. 
 
 219. The Present Status of Alkali. 
 
 220. Unfermented Fruit Juices. 
 
 228. Vineyard Irrigation in Arid Climates. 
 
 230. Testing Milk, Cream, and Skim Milk 
 
 for Butterfat. 
 
 231. The Home Vineyard. 
 
 232. Harvesting and Handling California 
 
 Cherries for Eastern Shipment. 
 
 233. Artificial Incubation. 
 
 234. Winter Injury to Young Walnut Trees 
 
 during 1921-22. 
 
 235. Soil Analysis and Soil and Plant Inter- 
 
 relations. 
 
 236. The Common Hawks and Owls of Cali- 
 
 fornia from the Standpoint of the 
 Rancher. 
 
 237. Directions for the Tanning and Dress- 
 
 ing of Furs. 
 
 238. The Apricot in California. 
 
 239. Harvesting and Handling Apricots and 
 
 Plums for Eastern Shipment. 
 
 240. Harvesting and Handling Pears for 
 
 Eastern Shipment. 
 
 241. Harvesting and Handling Peaches for 
 
 Eastern Shipment. 
 
 243. Marmalade Juice and Jelly Juice from 
 
 Citrus Fruits. 
 
 244. Central Wire Bracing for Fruit Trees. 
 
 245. Vine Pruning Systems. 
 
 No. 
 
 247. 
 248. 
 
 249. 
 250. 
 
 251. 
 
 252. 
 253. 
 254. 
 
 255. 
 
 256. 
 
 257. 
 258. 
 259. 
 260. 
 
 261. 
 262. 
 263. 
 264. 
 
 265. 
 266. 
 
 267. 
 
 268. 
 
 269. 
 270. 
 271. 
 
 272. 
 
 273. 
 
 275. 
 
 Colonization and Rural Development. 
 
 Some Common Errors in Vine Pruni»g 
 and Their Remedies. 
 
 Replacing Missing Vines. 
 
 Measurement of Irrigation Water on 
 the Farm. 
 
 Recommendations Concerning the Com- 
 mon Diseases and Parasites of 
 Poultry in California. 
 
 Supports for Vines. 
 
 Vineyard Plans. 
 
 The Use of Artificial Light to Increase 
 Winter Egg Production. 
 
 Leguminous Plants as Organic Fertil- 
 izer in California Agriculture. 
 
 The Control of Wild Morning Glory. 
 
 The Small-Seeded Horse Bean. 
 
 Thinning Deciduous Fruits. 
 
 Pear By-products. 
 
 A Selected List of References Relating 
 to Irrigation in California. 
 
 Sewing Grain Sacks. 
 
 Cabbage Growing in California. 
 
 Tomato Production in California. 
 
 Preliminary Essentials to Bovine Tuber- 
 culosis Control. 
 
 Plant Disease and Pest Control. 
 
 Analyzing the Citrus Orchard by Means 
 of Simple Tree Records. 
 
 The Tendency of Tractors to Rise in 
 Front r Causes and Remedies. 
 
 Inexpensive Labor-saving Poultry Ap- 
 pliances. 
 
 An Orchard Brush Burner. 
 
 A Farm Septic Tank. 
 
 Brooding Chicks Artificially, 
 
 California Farm Tenancy and Methods 
 of Leasing. 
 
 Saving the Gophered Citrus Tree. 
 
 Marketable California Decorative 
 Greens.