The Prevention of a Perosis-Like Condition in Turkey Poults1

The Prevention of a Perosis-Like Condition in Turkey Poults 1 J. R. HUNT 2 AND JAMES MCGINNIS Department oj Poultry Science, State College of Washington,

Pullman

(Received for publication October 14, 1958)

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WO types of enlarged hocks or perosis are observed in turkey poults. One type is characterized by hock enlargement, curvature and shortening of the tarsometatarsus and slipping of the tendon of Achilles from its condyle. The second is identical to the above except that the tendon of Achilles remains in position. The latter condition, commonly called enlarged hocks, was recently investigated by Scott (1950). The abnormality was recognized at 2 weeks and persisted to approximately 4 weeks of age, after which time the birds appeared normal. Scott (1951a) induced a high incidence of the enlarged hock disorder by feeding a corn-soy-casein diet containing fish liver oil. In further studies Scott (1951b) found the severity of the enlarged hocks to vary directly with the fish liver oil content of the diet except in the presence of dried brewers' yeast which completely prevented the condition. The beneficial factors present in dried brewers' yeast were found (Scott, 1953) to be niacin and vitamin E. The studies presented in this report are concerned with a similar, if not identical, deformity of young poults resulting from the feeding of an isolated soybean protein. EXPERIMENTAL METHODS AND RESULTS

The experimental procedure was the same in all the following experiments. Broad Breasted Bronze turkeys (not sexed) ' Scientific Paper No. 1784, Washington Agricultural Experiment Station, Pullman. Project No. 761.1. ' Present address: Poultry Division, Central Experimental Farm, Ottawa, Ontario, Canada.

were on experiment from hatching to four weeks of age in electrically-heated, wirefloored, battery brooders. Diets were allotted in a completely randomized design with each diet being fed to three groups of ten birds. Feed and water were supplied ad libitum. The composition of the basal diet is given in Table 1. Supplements to the basal diet were made at the expense of the carbohydrate source. Poults were weighed and observed for hock abnormalities at weekly intervals. A system of scoring the hock abnormality was used in which the percent incidence was recorded as well as the severity score (0 = normal, to 3 = most severe) for each pen. The 3 week results are given, as the TABLE 1.-—Composition of basal diet Ingredients

Sucrose Isolated soybean protein* (81%) Mineral mixf Cellulose Clarified raw soybean oil Vitamin mix J Methionine Procaine penicillin

Percentage composition

51.20 34.60 7.97 2.00 2.00 2.00 .20 5 ppm.

* Obtained from the Drackett Co., Cincinnati, Ohio. t Supplied the following in gm. per kg. of diet: 63.0; K2HPO4, 11.0; NaCl (Mineralized), 5.0; MgSOWHzO, 4.03; FeS0 4 , 0.834; and MnS0 4 (70%), 0.212. I Supplied the following per kg. of diet: Thiamine-HCl, 5.0; riboflavin, 10.0; d-calcium pantothenate, 20.0; niacin, 50.0; menadione (33%), 6.0; biotin, 0.1; pyridoxine • HC1, 5.0; folic acid (3%), 33.0; vitamin B12 (9.9 mg./lb.), 0.92 mg.; choline chloride (25%), 8.0 gms.; alpha locopheryl acetate (20,000 I.U./lb.), 25 I.U.; vitamin A (10,000 I.U./ gm.), 8,800 I.U.; vitamin D 3 (1,500 I.C.U.), 1,760 I.C.U.; and procaine penicillin (20% 5 ppm. Sucrose was added to make the vitamin mix up to 2.0 percent.

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PEROSIS-LIKE CONDITION IN POULTS

most extensive hock enlargement was observed at this period. Deviations from the experimental procedure are noted with each experiment. RELATION OF ISOLATED SOYBEAN PROTEIN TO HOCK DISORDER Preliminary experiments demonstrated that replacement of the isolated soybean protein with soybean oil meal completely prevented the occurrence of the enlarged hock disorder. Experiment 1: The extent to which the isolated soybean protein must be replaced with soybean oil meal to prevent the hock condition was studied. Soybean oil meal replaced the isolated soybean protein in increments of 20 percent of the protein of the diet. The results, presented in Table 2, demonstrate that when 60 percent of the protein of the diet is supplied by the isolated protein there is no evidence of hock enlargement. However, if the soybean oil meal is decreased to allow 80 percent of the dietary protein to be supplied by the isolated soybean protein, the hock abnormality appeared in 80 percent of the poults with a severity of 2.0. It would appear most likely that the soybean oil meal contains some factor(s) necessary for the prevention of the disorder; however, the concentration of isolated soybean protein could be insufficient to induce the hock abnormality if the causative agent(s) was contained in this material. The growth depression obtained when all of the protein was supplied by the isolated soybean protein may be due to amino acid imbalance. Supplementary experiments with arginine, lysine, methionine and glycine demonstrated that these supplementary amino acids did not improve growth when added to the purified diet. The texture of the diet was improved by the soybean oil meal, which may explain the growth response on diets high in this ingredient.

TABLE 2.—Replacement of isolated soybean protein with soybean oil meal and its relation to enlarged hocks Percent dietary protein Isolated soybean protein

Soybean

0 ( 0.0)* 20 ( 6.9) 40(13.8) 60(20.7) 80(27.7) 100(34.6)

100(63.6) 80(50.9) 60(38.2) 40(25.4) 20(12.7) 0 ( 0.0)

3 week hock weight Inci3 weeks, gm. dence Score

% 0 0 0 0 70 80

0.0 0.0 0.0 0.0 2.0 2.0

380 366 376 377 372 274

* Figures in parentheses give the percentage of each protein source in the diet. Sucrose was the other variable of the diet.

Other studies conducted at this laboratory on the effect of isolated soybean protein on enlarged hocks demonstrated that chicks (N.H. X W.O.) were unaffected by feeding diets containing as much as 61.8 percent of the isolated soybean protein. Experiment 2: A similar isolated soybean protein, "alpha-protein," was known to contain a large amount of bisulfite which is added as a preservative during manufacturing. Work of Miller et al. (1955) has shown the preservative, sodium bisulfite, increases the destruction of thiamine and vitamin E, but that this destruction could be prevented by water washing the alphaprotein. The isolated soybean protein used in these experiments may have contained a similar water soluble factor(s) that could be removed by washing. Unwashed isolated soybean protein was compared to an autoclaved unwashed sample, a washed sample and to a washed sample plus the carbonash of the unwashed protein. Autoclaving was carried out at 110°C. for 15 minutes. The protein was washed (mechanically stirred) with 10 times its weight of 60°C. tap water for 30 minutes. The material was allowed to settle for 1 hour and the supernatant removed. An additional amount of 60° C. water, equal to

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J. R. HUNT AI I J . MCGlNNIS

six times the weight of the protein supplement, was added and stirred for IS minutes after which time the suspension was filtered. The residue was dried in a forced draft oven at 70°C. for 24 hours. The carbon ash was prepared from an amount of unwashed isolated soybean protein equivalent to the amount in the basal diet. The protein concentrate was first charred under infra-red lamps for 4 hours then ashed at 660°C. for 2 hours. The muffle furnace contained insufficient oxygen to completely ash the material but the material was ignited to a carbon-ash mixture. As indicated in Table 3, washing of the isolated soybean protein completely removed or destroyed the factor(s) present in the protein concentrate which brought about the disorder in poults. The factor (s) does not appear to mineral because the carbon-ash of the protein concentrate did not induce the condition. However, the ignition may have brought about decomposition or volatilization of the causative agent(s). Autoclaving also gave no beneficial effect. Washing with distilled water gave the same beneficial effect as washing with tap water. The improvement in the hock condition by the water washing process led to a revaluation of the mineral mixture of the diet as water washing would be expected to have a marked effect on the free inorganic elements in the isolated soybean protein. In this and previous experiments potassium was added at the rate of O.S percent. The chick requirements for potassium was only 0.2 percent and the soybean protein was known to contain appreciable amounts of potassium; therefore, it was thought that O.S percent potassium might be excessive. The amount of potassium added was reduced to 0.3 percent of the diet in later experiments. This change in the potassium level of the diet had no effect on the incidence of enlarged hocks, the prevention of the condition by the water treatment, or the

TABLE 3.—Effect of washing, ignition, and autoclaving of the isolated soybean protein on the incidence of enlarged hocks 3 week hock enlargement Treatment of isolated soybean protein

Incidence

Score

Average 3 week weight, gm.

100 86 0 0

2.6 2.3 0.0 0.0

351 366 366 330

%

Unwashed Unwashed, autoclaved1 Washed Washed-f-carbon-ash 1

Autoclaved in dry chamber.

growth rate of the birds. Experiment 3: The action of washing the protein may not be in the removal of a toxic material (s) but rather, as in the case of linseed oil meal reported by McGinnis and Polis (1946), the improvement may be due to a reaction of the material with the water. This idea was tested by washing one batch of protein as described above; another batch was moistened with water in a ratio of 1.0:1.55 (the same ratio of protein to water as in the filtered protein after washing) for the same length of time as was required in the washing procedure; a third batch had no water treatment. All batches were placed in a drier together and remained in the drier for the same length of time. An unwashed sample was used as a negative control. The results are in Table 4. The 2 week hock enlargement was used in this experiment because the condition returned to normal earlier than usual. The unwashed material gave the same high incidence of hock enlargement which was completely prevented by replacement with washed isolated soybean protein. Wetting the protein concentrate gave a marked improvement over the unwashed, but heat had only a small effect. Previous experiments had shown that evaporating the wash-water to dryness and feeding the residue to poults failed to induce the hock abnormality. Effect of Vitamin Supplementation on

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PEROSIS-LIKE CONDITION IN POULTS TABLE 4.—Effect of welting, washing, and heating the isolated soybean protein on the incidence of enlarged hocks in turkey poults

Treatment of isolated soybean protein

2 week hock enlargement Incidence

% Unwashed Washed Wetted 1 Heated 2

100 0 11 63

Score

Average 3 week weight, gm.

1.6 0.0 0.3 1.0

338 370 370 365

1 Sufficient water added to give the same moisture content as the filtered washed protein for the same time period as the washing procedure. 2 No water treatment but place in the drying oven for the same length of time as the wetted and washed protein.

the Incidence of Enlarged Hocks Experiment 4: Results of Scott (1951b) demonstrated that dried brewers' yeast was beneficial in alleviating enlarged hocks. It was later shown (Scott, 1953) that 20 mg. of niacin in combination with 5 mg. of alpha tocopheryl acetate would replace the preventive action of the dried brewers' yeast. This experiment was designed to note if the enlarged hock syndrome occurred in niacin deficient poults. The effect of supplementing niacin, vitamin E and diphenyl-p-phenylenediamine (DPPD) alone and in combination was observed under these conditions. The basal diet used in this experiment is given in Table 5, while the results are presented in Table 6. Microbiological assay of

the basal diet using the method of BartonWright (1944) showed the niacin content of the basal diet to be 7.25 mg. per pound. It is clearly demonstrated that enlarged hocks can be induced by reducing the niacin content of the diet; this result agrees with the work of Briggs (1946) and Scott (1953). Supplementation of the basal with 4 mg. of niacin per pound resulted in a significant growth response; an additional supplementation of 8 mg. of niacin gave a growth response approaching significance. Further supplementation did not improve growth. Enlarged hocks occurred in both the unsupplemented diets and the diets containing 4 mg. of supplementary niacin; 8 mg. of supplementary niacin prevented the abnormality. The addition of alpha tocopheryl acetate or DPPD to the diet had no effect on the incidence of the hock abnormality or growth of the poults. The external physical characteristics of the enlarged hocks induced by a niacin deficiency did not differ from those induced by the unwashed isolated soybean protein. Experiment 5: Because Scott (1951b) had reported the beneficial effect of dried brewers' yeast, an excellent source of the B complex vitamins, and a deficiency of niacin TABLE 6.—Effect of niacin, vitamin E and D.P.P.D.* on the occurrence of enlarged hocks induced by a niacin deficient diet 3 week hock enlargement

TABLE 5.—Composition of niacin deficient basal diet Ingredients Ground corn Washed isolated soybean protein Flaked gelatin Mineral mix* Clarified raw soybean oil Vitamin mixf DL-Methionine Procaine penicillin

Percent of diet 59.50 22.80 5.00 7.97 2.00 2.00 0.50 5 ppm.

* As in Tablet. f As in Table 1 except the omission of niacin and alpha tocopheryl acetate from the mix.

of basal

Incidence

Score

weight, gm.

2.3 1.0 0.0 0.0 2.0

437 513 558 585 443

50

1.6

554

3

0.6

608

0 100 16 0 0

0.0 3.0 1.3 0.0 0.0

579 486 548 594 554

% None Niacin, 4 mg. Niacin, 8 mg. Niacin, 12 mg. Alpha tocopheryl acetate, 25 I.U. Niacin, 4 m g . + a l p h a tocopheryl acetate (25 I.U.) Niacin, 8 m g . + a l p h a tocopheryl acetate Niacin, 12 m g . + a l p h a tocopheryl acetate D.P.P.D.* Niacin, 4 m g . + D . P . P . D . Niacin, 8 m g . + D . P . P . D . Niacin, 12 m g . + D . P . P . D .

diet.

100 30 0 0 93

N, N1 diphenyl-p-phenylenediamine at 0.05 percent of the

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J. R. HUNT AI

had produced enlarged hocks in the previous experiment, high level vitamin supplementation was carried out to attempt to replace the effect of washing isolated soybean protein. All the vitamins of the premix were fed at a IS fold increase of the basal level alone and in combination. No attempt was made to supply the vitamin in a purer form than was used in the basal diet. The results, presented in Table 7, indicate that the inclusion of all the vitamins at the high level prevents the hock disorder in the presence of the unwashed isolated soybean protein. On the other hand, none of the B complex vitamins alone would prevent the condition when added at the high level to the unwashed protein diet. Washing the protein concentrate and adding it to the diet again prevented the hock abnormality. Experiment 6: It appears that a combination of several vitamins may be required to prevent the enlarged hock condition in the presence of the unwashed protein concentrate. This experiment was designed so that all possible combinations of riboflavin, calcium pantothenate, niacin, folic acid, pyridoxine and biotin are fed at a IS fold increase, together with high levels of the fat soluble and remaining B complex vitamins. Again, no attempt was made to use more highly purified sources of vitamins than were used in the basal diet. Because of the large amount of vitamins required in this test, only two groups of ten birds each were fed the experimental diets to two weeks of age. As indicated in Table 8, the supplementation of the basal diet with high level of the fat soluble vitamins alone or in combination with high levels of thiamine, vitamin B12 and choline chloride had little effect on reducing the severity and occurrence of the disorder. On the other hand, if all the vitamins are present at the high level the abnormality is completely prevented. This protection was also obtained when several

J. MCGINNIS TABLE 7.—Effect of single and combination of high level vitamin supplementation on the development of enlarged hocks 3 week hock enlargement Supplement to basal*

Incidence

Score

Average 3 week weight, gm.

1.6 0.0 2.0 2.0 1.6 1.6 2.3 1.6 1.6 1.6 2.0 0.0 0.0

364 346 347 352 360 359 326 371 350 379 365 348 395

% None All vitamins Thiamine HC1 Riboflavin d-calcium pantothenate Niacin Pyridoxine HC1 Folic acid Vitamin B12 Biotin Choline chloride

Nonef All vitaminsf

100 0 100 100

so

77 100 62 83 66 100 0 0

* All supplements added to give a 15 fold increase in the basal level. The same source of vitamins was used as in Table 1, with no attempt made to use more concentrated vitamin sources. t Contain washed isolated soybean protein, all other treatments contain unwashed isolated soybean protein.

of the B complex were present at the high level but the presence or absence of any one or combination of vitamins could not be correlated with the prevention of the hock disorder. DISCUSSION These experiments have demonstrated that the perosis-like condition or enlarged hocks could be induced by: (1) a niacin deficiency and (2) the incorporation of an isolated soybean protein into the purified diet. Briggs (1946) found perosis to be associated with a niacin deficiency. Scott (1953) found niacin and vitamin E necessary to prevent enlarged hocks induced by feeding a corn-soybean-casein diet containing 2 percent fish liver oil. The work reported in this paper agrees with the finding that niacin is essential to prevent the hock abnormality induced by an insufficiency of this vitamin but could not find any beneficial effect from vitamin E or the antioxidant DPPD for the prevention of the

PEROSIS-LIKE CONDITION I N POULTS

TABLE 8.—Effect

of combinations of high level vitamins on the occurrence of hock disorder Supplements to basal*

Vitamin A,D, E, K

+ + + + + + + + + + + + + + + + + +

Vit. Bi, B12, choline

+ + + + + + + + + + + + + + + + + +

Riboflavin

+ + + + + + + + + + +

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d-Ca pant.

+ + + + + + + + + + +

Niacin

+ + + + + + + + + + +

2 wk. hock • enlargement Vit. B6

+ + + + + + + + + + +

Folic acid

+ + + + + + + + + + +

Biotin

+

+ + + + + + + + + +

Incidence Score % 65 100 60 0 0 0 17 5 10 0 30 0 25 50 15 5 0 11 20 55

1.5 2.0 1.5 0.0 0.0 0.0 0.5 0.5 0.5 0.0 O.S 0.0 0.5 0.5 0.5 0.5 0.0 0.5 0.5 1.0

Average 2 week weight gm. 215 209 225 226 222 214 221 221 236 229 211 230 218 218 210 230 220 207 228 230

* All supplements added to supply 15 fold increase in the basal level. Same source of vitamins were used as in Table 1.

abnormality. It was found that 11 to 15 mg. of niacin per pound of diet would support maximum growth and prevent the enlarged hock syndrome induced by a deficiency of this vitamin. The hock enlargement induced by the isolated soybean protein could not be prevented by feeding as high as 340 mg. of niacin per pound of diet. Although the conditions induced by the niacin deficiency and the isolated soybean protein appear, from visual observation, to be identical, variation in the cause and prevention of the condition occur. The condition was directly associated with the isolated soybean protein of the diet and was species specific for the turkey poult while ineffective to the chick under the experimental conditions. Washing of the protein concentrate completely prevented the development of the abnormality. Apparently, the water washing did not remove some factor or factors

but rather reacted with the factor(s). Such a reaction could hydrolyze and degrade a toxic factor or denature the protein and release an essential nutrient. The possibility of steam distillation in the drying process cannot be disregarded. It is interesting to note the work of McGinnis and Polis (1946). These workers found that the nutritional value of linseed oil meal was improved by wetting the material with water over night. Kratzer and Williams (1948) reported similar results: in that water treated linseed oil meal gave increased growth and that the improvement could also be obtained by increasing the pyridoxine level of the diet. Work reported herein indicates that no single vitamin is related to the condition. Supplee et al. (1958) report the occurrence of a non-rachitic hock disorder and abnormal feathering in turkey poults fed a washed-Drackett-sucrose diet. These workers found that supplementing the diet

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J. R. HUNT AND J.

with 0.01 percent ZnCl2 gave a dramatic improvement in hock and feather condition. Growth was improved slightly by the addition of 0.01 percent ZnCl2 and markedly by 0.3 percent KC1, unidentified growth factor mixture, ash of the unidentified factor mixture, ash of 5 percent dried distillers solubles, and oleandomycin. They report that a steam-sterilized washed Drackett protein-starch diet rarely induces abnormal hocks. Their mineral mixture was identical to that used in their sucrose basal but the vitamin mixture before sterilization was much higher. In contrast, in the work reported herein enlarged hocks was prevented when the Drackett protein was washed in 60°C. water. Supplee and associates, however, did not use hot water in washing the Drackett protein but when they used heat in the sterilization of the Drackett protein they rarely observed enlarged hocks. In the autoclaving procedure used in the experiment reported herein, steam did not enter the chamber but was confined to the jacket of the autoclave. This may explain the differences in results with washing and autoclaving. Also, no reduction in growth occurred when the potassium level of the diet was reduced from 0.54 percent to 0.34 percent. The basal diet had a calculated level of 42 ppm of zinc which was below the preventive level of 58 ppm reported by Supplee et al. (1958). Water washing of the protein would be expected to reduce the amount of both these elements. Several toxic factors have been found in soybean oil meal. A trypsin inhibitor was isolated and crystallized by Kunitz (1947) from raw soybean oil meal. The inhibitor is a protein which was inactivated by autoclaving and pepsin digestion. Autoclaving had no effect on the factor(s) present in the isolated soybean protein. Furthermore, the inactivity of the factor(s) in the chick suggest that the factor (s) is not similar to the trypsin inhibitor. Liener (1953) re-

MCGINNIS

ported the identification of a toxic protein termed soyin which makes up approximately 3 percent of soybean oil meal. Soyin differs from the trypsin inhibitor in that it does not conjugate with trypsin; this fact was demonstrated by feeding rats crude trypsin in the presence of soyin. Paired feeding trials demonstrated that the toxic materials reduced growth by reducing feed consumption. Soyin was inactivated by autoclaving but the factor(s) which induces enlarged hocks was found to be unaffected by this treatment. The action of the high levels of vitamins requiring the presence of all B complex vitamins and not just a specific group of vitamins is very difficult to explain. In most reports of antagonists and toxic factors, one or a combination of a few vitamins were necessary to overcome their adverse effect. However, the results obtained in these investigations show that several different groups of vitamins would replace the effect of all the B complex vitamins but no specific groups were required. A recent report of Hill (1955) presented evidence that the resistance of chicks to Salmonella gallinarum could he greatly enhanced by a ten-fold increase in the vitamin levels recommended by the National Research Council. Single vitamin supplementation, the exclusion of a single vitamin from the vitamin supplement, or the supplementation with only the fat or water soluble vitamins at the high level, did not increase the resistance to the microorganisms. No explanation was offered for this phenomenon. It is possible that a toxic material present in the isolated soybean protein reacts similarly in that it requires a high level of manyvitamins to prevent the condition, but no specific group of vitamins. SUMMARY

Feeding a purified diet which contained an isolated soybean protein was found to

PEROSIS-LIKE CONDITION IN POULTS

induce enlarged hocks in turkey poults from 2 to 4 weeks of age. The occurrence of the enlargement was found to be directly associated with the isolated soybean protein of the diet. The enlarged hock condition could be prevented by washing the protein concentrate with water (60°C.) or by the addition of all vitamins at a 15 fold increment over the basal level. The alleviation of the enlarged hock condition by washing could almost be accomplished by simply wetting the protein and drying it in an oven at 70°C. The preventive effect of the high level vitamin supplementation could not be associated with a single or combination of vitamins but several combinations were found to give protection but had no common factors. REFERENCES Barton-Wright, E. C , 1954. The microbiological assay of nicotinic acid in cereal and other products. Biochem. J. 38: 314-319. Briggs, G. M., 1946. Nicotinic acid deficiency in turkey poults and the occurrence of perosis. J. Nutrition, 3 1 : 79-84. Hill, C. H., H. W. Garren, J. W. Kelley and C. W. Barber, 1955. Effect of nutrition on the resistance of chicks to fowl typhoid. Fed. Proc. 14: 437.

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Kratzer, R. H., and D. E. Williams, 1948. The relation of pyridoxine to the growth of chicks fed a ration containing linseed oil meal. J. Nutrition, 36: 297-305. Kunitz, M., 1947. Crystalline soybean trypsin inhibitor. 2. General properties. J. Gen. Physiol. 30: 291-298. Liener, I. E., 1953. Soyin, a toxic protein from a soybean. I. Inhibition of rat growth. J. Nutrition, 49: S27-S39. McGinnis, J., and H. L. Polis, 1946. Factors affecting the nutritional value of linseed meal for growing chicks. Poultry Sri., 25: 408. Miller, R. F., G. Small and L. C. Norris, 1955. Studies on the effect of sodium bisulfite on the stability of vitamin E. J. Nutrition, 55: 81-95. Scott, M. L., 1950. Studies on the enlarged hock disorder (perosis) in turkey poults. J. Nutrition, 40: 611-624. Scott, M. L., 19Sla. Studies on enlarged hock disorder in turkeys. 2. Factors affecting the excretion and retention of creatine by young poults. Poultry Sci. 30: 839-845. Scott, M. L., 1951b. Studies on enlarged hock disorder in turkeys. 3. Evidence of the detrimental effect of fish liver oil and the beneficial effect of dried brewers' yeast and other materials. Poultry Sci. 30: 846-855. Scott, M. L., 1953. Prevention of enlarged hock disorder in turkeys with niacin and vitamin E. Poultry Sci. 32: 670-677. Supplee, W. C , G. F. Combs and D. L. Blamberg, 1958. Zinc and potassium effects on bone formation, feathering and growth of poults. Poultry Sci. 37: 63-67.

NEWS AND NOTES (Continued from page 611) rary instructor in the department and will carry out teaching duties in products and marketing and will take over the coaching of the judging team. The department plans to move into new facilities in an Animal Science Building in the early fall. This building will provide physiology and nutrition laboratory facilities as well as an incubator laboratory and two controlled environmental chambers. HALL OF FAME In February, the American Poultry Historical Society approved the names of eighteen poultry fanciers, prominent in the period of 1875 to 1925, (Continued

to be honoured in the Poultry Hall of Fame, housed at the University of Maryland, College Park. The names will be listed on a plaque. Those honoured are: Victor Bradley, Mass.; William Ellory Bright, Mass.; Bird Brothers, Pa.; Wid H. Card, Conn.; Maurice F. Delano, Mass.; Isaac K. Felch, Mass.; Harry Graves, Conn.; John S. Martin, Ontario, Canada; Charles McClave, Ohio; George Robertson, Ontario, Canada; John H. Robinson, Mass.; Arthur O. Schilling, New York; Franklane Sewell, Ohio; Arthur O. Smith, Mass.; Lester Tompkins, Mass.; E. B. Thompson, New York; Philander Williams, Mass.; and Dan W. Young, New York. on page 649)