Effect of an Antibiotic on Egg Production

REPRODUCTION

Flagg, C. O., 1896. Crossbreeding of geese. Rhode Island Agr. Exp. Sta. 9th Annual Report: 355358. Flagg, C. O., 1897a. Experiments with geese. Rhode Island Agr. Exp. Sta. 10th Annual Report : 481-617. Flagg, C. O., 1897b. Goose breeding. Rhode Island Agr. Exp. Sta. 10th Annual Report: 409-480. Hoffman, E., and B. Hancock, 1950. The effect of

IN

GEESE

783

length of day on egg production of geese and guineas. Poultry Sci. 29: 469-471. Hutt, F. B., 1949. Genetics of the Fowl. McGrawHill Book Co., Inc., New York. Johnson, A. S., 1950. Central Exp. Farm, Ottawa. Private communication. Randies, C. A., 1947. Studies on the domestic goose and artificial incubation of goose eggs. Unpublished M.S. Thesis, Columbus, Ohio, Ohio State University Library.

H. D. BRANION, D. C. HILL AND H. G. JUKES Department of Nutrition,

Ontario Agricultural College, Guelph, Ontario, Canada

(Received for publication January 18, 1956)

' I V HE published results of experiments caine penicillin, or streptomycin, or terra•** designed to investigate the effect of mycin, at a level of about 9 grams per ton, the inclusion of an antibiotic in the ration to the ration of duplicate lots of 65 White of laying birds upon egg production are Leghorn pullets each, during the first year contradictory. Halbrook and Beeckler of production, did not improve egg produc(1951) reported that the addition of a tion. Berg et al. (1952) reported, as a vitamin Bi2-antibiotic supplement, con- result of three experiments involving 1232 taining 1.8 mg. of vitamin B12 and 1.8 gm. White Leghorn pullets, that the addition of aureomycin per pound, to the rations of of aureomycin or terramycin to various White Leghorn and New Hampshire chick- rations, at levels ranging from 4 to 15 ens, or Bronze turkeys gave no consistent p.p.m., had no effect upon egg production. improvement in egg production. Carver et Sunde et al. (1952) found that the addial. (1951) found that the feeding of either tion of 0.25 percent of an antibiotic feed aureomycin or terramycin, at a level of supplement, containing 1.8 gm. of aureo10 p.p.m. in either an all plant protein mycin per pound and some vitamin Bi2, ration or a ration containing fish meal, to did not improve egg production in experiduplicate groups of 40 Leghorn pullets ments conducted with groups of 20 White each, had no effect upon egg production. Leghorn pullets each, in two different Similarly, with duplicate groups of 59 Leg- years. Waibel et al. (1952) reported that horn pullets each, terramycin added to a the addition of either 5 or 200 p.p.m. of soybean oil meal—fish meal diet at levels of penicillin, to a practical ration, gave no 4, 8 and 12 p.p.m. had no effect. Lillie and measurable effect on egg production. HowBird (1952), using Rhode Island Red pul- ever there were only 4 or 6 White Leghorn lets in groups of 35 each, obtained no sig- pullets in each group. Sizemore et al. nificant difference in egg production as a re- (1953) fed aureomycin, supplied as 0.5 sult of the addition of 1 percent of a vitamin percent of a vitamin Bi2-antibiotic suppleB12-aureomycin supplement to a vitamin ment containing 1.8 mg. of vitamin B12 B12 low diet. Petersen and Lampman and 1.8 gm. of aureomycin hydrochloride (1952) concluded that the addition of pro- per pound, to Rhode Island Red pullet

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Effect of an Antibiotic on Egg Production

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H. D. BRANION, D. C. HILL AND H. G. JUKES

effect upon egg production. On the other hand, Reid et al. (1951) reported that the egg production of White Leghorn pullets was increased by raising the level of an aureomycin "animal protein factor" supplement from 0.25 to 1.0 percent, or by feeding aureomycin hydrochloride at a level of 66 p.p.m. in the ration in place of the APF supplement. The substitution of crystalline vitamin B12 for the APF supplement did not affect egg production, but it was increased by feeding aureomycin with the vitamin. The data of Elam et al. (1951) show that the feeding of penicillin to New Hampshire X White Leghorn pullets at a level of 33 p.p.m. in the ration did not improve egg production, but the injection of 1 meg. of vitamin B12 per bird per week may have increased egg production, and the feeding of penicillin in combination with injection of B12 appeared to increase production still more, although the number of birds involved was small. However, in a later report (Elam et al., 1953) the authors summarized the above experiment—"penicillin increased egg production." Atkinson and Couch (1951) concluded that egg production, as judged by 4 Broad Breasted Bronze turkey poults per group, was increased by the feeding of aureomycin at a level of 25 p.p.m. of the ration, aureomycin at a 66 p.p.m. level with 13 meg. of vitamin B i 2 per kilogram of ration, injection of 2 meg. of B i 2 per bird per week, 6 percent of fish meal, 2 percent of an aureomycin APF concentrate, or 4 percent liver "L." The highest egg production was obtained by adding 25 p.p.m. of aureomycin to the ration. Petersen et al. (1952) found that the addition of 0.25 percent of an antibiotic and vitamin B12 supplement to a vitamin B i 2 deficient diet fed to duplicate groups of 30 White Leghorn pullets, improved egg production. This may have been due to either its vitamin B 12 content or aureomycin content, or

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chicks, receiving the Connecticut broiler ration or a corn-soybean meal diet, from hatching to 22 weeks. At that time the pullets were subdivided into various groups of 36 or 40 each, and continued on either a B12-low diet with and without crystalline aureomycin, or on a standard ration. The presence or absence of the antibiotic either in the grower, or in the breeder diets subsequently fed, had no influence upon egg production, nor did graded levels of 5, 10, 20 and 40 p.p.m. of aureomycin in the breeder diet. Sherwood and Milby (1953) reported that, in one experiment with yearling or old White Rocks and White Leghorns, the inclusion of aureomycin at a level of 20 grams per ton in the ration had no effect on egg production. In a second experiment, with White Rock pullets, aureomycin fed in a 60-40 mash-grain ration at a level of 180 grams per ton of mash, had no effect on egg production, nor did low level penicillin feeding in a third experiment. Brown et al. (1953) found that the addition of penicillin, furnished by 1 percent of an APF and antibiotic supplement, to three practical type breeding rations, which varied in protein or energy level, had no effect on rate of egg production in groups of 33 White Leghorn pullets. Bearse and Berg (1955) fed either a high or a low energy diet to groups of 65 White Leghorn pullets, with 0, 10 and 100 grams of aureomycin per ton of ration. Although there was a tendency for the total number of eggs laid to be higher for the groups receiving the antibiotic, the difference was not significant. Sizemore et al. (1955a), reporting on the second year of their tests with Rhode Island Red hens reared on the Connecticut broiler ration with and without aureomycin, or on a corn-soybean meal diet with or without aureomycin, concluded that the presence or absence of the antibiotic either in the growing or breeder diets had no

ANTIBIOTIC AND EGG PRODUCTION

Although some of these conclusions would appear to be based upon results with groups of laying birds inadequate in number to reveal real differences in production, and that inadequate vitamin B12 intake was a complicating factor in some experiments, the fact remained that the evidence

with regard to the influence of antibiotics upon egg production was contradictory. Nor could these opposite conclusions be explained upon the basis of breed or of type of antibiotic used. However, evidence was accumulating that environment, in its broad sense, might be the determinant factor. Carlson et al. (1953) reported that the addition of penicillin at a level of 24 grams per ton in the mash portion of a mashgrain ration in one year, and at 4 grams per ton of ration in another year, slightly improved egg production in three of four trials. The addition of 60 grams of streptomycin per ton of mash, in a mash-grain ration, improved egg production in all experiments. Although their published results did not include data obtained during the height of an outbreak of Newcastle disease during the second year of experiment, the authors state that the egg production of the antibiotic-fed hens, New Hampshire and White Rocks, dropped less than that of the controls. Balloun (1954) concluded that, under conditions unfavourable to high egg production, the addition of antibiotics at a high level, may improve egg production. Production increased an average of 40 percent in 8 lots, of 9 to 12 New Hampshire pullets, after the addition of 100 grams of aureomycin per ton of diet, following a decline in production for 4 months. In 4 lots of birds, continued on the diets without antibiotic supplementation, no change in egg production occurred. The greatest increase in production, following the addition of aureomycin, was obtained with birds fed an all plant diet. Lillie and Sizemore (1954) divided meat type New Hampshire pullets into low producing groups of 20 birds each, and high producing groups of 23 birds each, and fed an all plant protein diet, low in vitamin B 12 . The addition of a vitamin B12-antibiotic supplement improved the egg production of

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to both. Elam et al. (1953), using groups of 10 New Hampshire pullets, concluded that the addition of 33 p.p.m. of penicillin or of bacitracin, to a vitamin B12-deficient ration, increased egg production. The injection of 1.2 mg. of penicillin per bird per week, or of 15,000 units of penicillinin-oil every other day, increased egg production. However, the injection of 1.2 mg. of bacitracin per bird per week did not increase egg production, nor did the oral administration of inactivated penicillin at a level of 33 p.p.m. in the ration, but the injection of 1.2 mg. per bird per week did increase production. With vitamin B 12 in the diet, oral administration of penicillin, inactivated penicillin and bacitracin, at the above levels, increased egg production, as did injections of penicillin, penicillin-in-oil, inactivated penicillin and bacitracin. Boone and Morgan (1955) found that low levels of aureomycin, penicillin, terramycin or bacitracin, fed from hatching to the end of the first laying year, resulted in increased egg production, which approached significance in some instances. Sizemore et al. (1955b) reared groups of chicks on a growing diet alone or supplemented with vitamin B 12 , or aureomycin, or a combination. At 22 weeks of age, groups of 6 birds from each growing diet were fed a vitamin B i 2 deficient diet alone, or supplemented with aureomycin, or B12, or a combination. Comparable groups were housed on wire floors and sawdust litter. There was significantly higher egg production in these groups on litter whose laying diets were supplemented with vitamin Bi2 or a combination of B12 and aureomycin.

785

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H. D. BEANION, D. C. HILL AND H. G. JUKES

to birds whose production efficiency was high. However, even these birds gave statistically higher egg production. Fifty grams of aureomycin per ton of ration was optimal for light breeds, whereas 100 grams per ton was optimal for heavy breeds. The feeding of 100 to 200 grams of aureomycin per ton of ration significantly increased the egg production of Beltsville Small White turkeys. EXPERIMENTAL

In the fall of 1954, pullets of heavy breeds, which had been reared on range and fed rations containing low levels of penicillin, were housed in individual cages in 6 laying batteries in one room. The temperature of this room was maintained at 60°F. during cold weather by controlled heating units but the temperature was not controlled during hot weather except insofar as could be achieved by exhaust fans. On October 1 all birds were placed on an all-mash ration containing ground wheat 55.0 lb., ground yellow corn 22.75 lb., dehydrated cereal grass 2.50 lb., meat meal (50% protein) 2.50 lb., fish meal (65% protein) 1.50 lb., dried skimmilk 1.50 lb., soybean oil meal (44% protein) 10.0 lb., ground limestone 2.0 lb., feeding bone meal 1.75 lb., iodized salt 0.50 lb., vitamin A concentrate (10,000 I.u./gm.) 0.05 lb., dry vitamin D 3 supplement (1650 I.C.u./gm.) 0.05 lb., manganese sulphate (feed grade) 0.0125 lb., riboflavin 0.05 gm., and vitamin B 12 0.15 mg. This ration contained about 16.6 percent crude protein, 1.7 percent calcium and 0.7 percent phosphorus. Oyster shell and granite grit were supplied ad libitum. On November 1, the pullets were randomized into groups of 48 so that each battery contained 20 Columbian Rocks, 8 White Rocks, 3 Barred Rocks and 17 heavy crossbreds. These consisted of equal numbers of 4 different crosses between heavy

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the low producers but not that of the high producers. Sherwood and Milby (1954) reported that the addition of either 10 grams of terramycin per ton of ration, or 12 or 100 grams of aureomycin, or 4 grams of penicillin, or from 21.4 to 36.8 grams of a mixture of aureomycin and terramycin, to various groups of White Rocks, White Leghorns or heavy crosses, ranging in number from 17 to 236, had no effect upon egg production. In some experiments the results favoured the use of antibiotics, in others the controls gave better production, the average production of all birds fed the control diets being 53.7 percent as compared to 54.4 percent for the birds receiving antibiotics. The authors suggested that the suppression of a sub-clinical disease condition by the antibiotic may have been responsible for the favourable results in some of the published reports. Heywang (1954) reported that, during 100 days of hot weather, the egg production of White Leghorn pullets was increased by supplementing their ration with 50 or 100 grams of aureomycin per ton. Jacobs et al. (1955) used White Leghorn pullets that had been exposed to respiratory diseases on range, housed in laying batteries and fed high and low levels of penicillin and streptomycin. The high levels, 50 to 100 grams per ton, increased egg production 10 and 19 percent over a seven month period. WhiteStevens et al. (1955) reported the results of nine field experiments, involving more than 18,000 White Leghorn and New Hampshires, carried out over a two year period in various sections of the United States. The levels of aureomycin fed varied from 50 to 200 grams per ton of ration. In general, the antibiotic significantly increased egg production. The differences due to the antibiotic were significantly greater when it was fed to birds undergoing stress from certain diseases, particularly chronic respiratory disease, than when it was fed

787

ANTIBIOTIC AND EGG PRODUCTION

RESULTS AND DISCUSSION The results are shown in Table 1. Percentage egg production was calculated on a hen day basis, including the day preceding the death of a bird. Feed conversion as pounds of feed per dozen eggs, was based on total mash consumption, not including the oyster shell and grit, and the total egg production of the 96 birds started on test on each diet. The egg production data were subjected to statistical treatment (Snedecor, 1946), based on the average number of eggs laid per bird on each diet, which survived the test; that is, the production of all birds which died during the test was disregarded in this analysis. Two birds, one on the control diet and one on the diet containing 10 p.p.m. of aureomycin, did not

lay during the test. They were also ignored in the statistical analysis. On this basis, the average number of eggs laid per bird in the control groups was 85.9, in the groups receiving 10 p.p.m. it was 89.4, and in the groups receiving 100 p.p.m. was 97.9. The increased production of the groups receiving the high level of aureomycin was significantly greater than that of the controls, between the 1 and 5 percent point of probability However the production of the group receiving 100 p.p.m. of aureomycin was not significantly greater than that of the group receiving 10 p.p.m. nor was the production of the latter group significantly higher than that of the controls. However, it would seem reasonable to conclude that the high level of aureomycin did increase egg production, and that the low level may have been of some benefit. During the latter part of December and in January there appeared to be a mild respiratory infection in some birds in all groups, as evidenced by some head shaking, slight mucoid discharge from the nostrils and mild sneezing. There was no evidence that this infection was responsible for any mortality, although it could have been a contributory factor. These results would support the results

T A B L E 1.—Results of feeding aureomycin

to laying

birds Feed conversion f, lb. feed per dozen eggs

Mortality

45.3

6.1

16

46.1

6.1

19

52.2

5.5

10

Percentage egg production* Diet

Battery December

Control

2

50.3

6

54.8

January 46.3

100 p.p.m. aureomycin

1

47.2

5

52.8

46.0 50.0

3

63.2

4

62.3

45.4 53.2

52.5

57.3 62.7

48.7 55.4

56.3

43.4 37.5 48.8

35.4

51.2

35.2 37.5

46.7 47.0

47.5

39.7

46.5 50.7

52.7

31.7

43.0 42.4

Average 42.9

31.5

43.6 46.6

49.9

54.5 58.7

60.1

38.9

43.3

May 32.3

40.2

50.3

46.3 53.5

April 41.6

52.8

39.4 51.4

56.9

March 47.7

37.3 49.4

52.6% 10 p.p.m. aureomycin

February

39.7

53.2

Number of eggs -X100. Number of hensXdays t Based on total mash consumed, not including oyster shell or grit, and the total egg production of 96 birds started on test on each diet. X Average production of all birds in both batteries.

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breeds. No culling, except for those birds which were found to be in poor condition at time of housing, was done. On this date the ration of the birds in batteries 1 and 5 was supplemented with 10 p.p.m. of aureomycin hydrochloride (chlortetracycline hydrochloride), and of those in batteries 3 and 4 with 100 p.p.m. The birds in batteries 2 and 6 served as controls. Egg production and feed consumption were recorded from December 1 to May 31, inclusive, a period of 6 months.

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H. D. BEANION, D. C. HILL AND H. G. JUKES

SUMMARY The inclusion of aureomycin (chlortetracycline hydrochloride) at levels of 10 and 100 p.p.m. in an all-mash ration, fed to duplicate groups of 48 heavy breed birds each housed in laying batteries appeared to increase egg production over a six months period. The production of the groups receiving the higher level was significantly greater than that of the controls, but it was not significantly greater than that of the groups receiving 10 p.p.m., nor was the production of the latter groups significantly greater than that of the controls. These birds suffered a mild respiratory infection for about six weeks during the

test and the results support previous conclusions that high level feeding of antibiotics increases egg production under such stress conditions. ACKNOWLEDGMENT

The aureomycin was supplied by the Lederle Laboratories Division, American Cyanamid Company, Pearl River, N.Y., and the vitamin B12 by Merck and Co., Montreal, Quebec. REFERENCES Atkinson, R. L., and J. R. Couch, 1951. The effect of vitamin Bi2, APF concentrate, aureomycin, streptomycin, liver "L" and fish meal on egg production and hatchability of Broad Breasted Bronze turkeys. Poultry Sci. 30: 905906. Balloun, S. L., 1954. Effect of high level aureomycin feeding on rate of egg production. Poultry Sci. 33 : 867-869. Bearse, G. E., and L. R. Berg, 1955. The effect of varying levels of aureomycin on the performance of young laying chickens. Poultry Sci. 34: 1180. Berg, L. R., J. S. Carver, G. E. Bearse and J. McGinnis, 1952. Antibiotics in the nutrition of laying hens. Washington Agric. Expt. Sta. Bull. 534. Boone, M. A., and C. L. Morgan, 1955. Effects of various antibiotics on broilers and laying hens. Poultry Sci. 34: 1231. Brown, J. A., A. R. Robblee and D. R. Clandinin, 1953. The use of penicillin in breeding rations. Poultry Sci. 32: 576-578. Carlson, C. W., R. A. Wilcox, W. Kohlmeyer and D. C. Jones, 1953. The effect of penicillin and streptomycin in diets for breeding hens. Poultry Sci. 32: 176-178. Carver, J. S., J. McGinnis, L. R. Berg and G. E. Bearse, 1951. The effects of antibiotic supplements on egg production. Poultry Sci. 30: 909-910. Elam, J. F., L. L. Gee and J. R. Couch, 1951. Effect of feeding penicillin on the life cycle of the chick. Proc. Soc. Expt. Biol. Med. 77: 209-213. Elam, J. F., R. L. Jacobs and J. R. Couch, 1953. The effect of prolonged feeding of antibiotics upon the performance of laying hens. Poultry Sci. 32: 792-795.

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of other workers that high levels of an antibiotic will increase egg production when the birds are under "stress," such as a respiratory infection. The monthly egg production data suggest that the higher level of aureomycin exerted its greatest effect in the first two months following its addition. It is unfortunate that records for November were not kept. There is a chance that, in the randomization of the individuals of the various breeds into the batteries at the beginning of November, birds laying at a higher rate were placed in the groups receiving the higher level of the antibiotic, but it seems unlikely that this would have occurred in both batteries housing the birds on this diet. There is also an indication that both levels of aureomycin sustained egg production at a higher level in the last two months of the test. The mortality data could be interpreted as supporting evidence that the higher level of aureomycin feeding aided in maintaining the health of the birds. The higher level of aureomycin resulted in increased feed efficiency, as judged by the amount of feed required per dozen eggs.

ANTIBIOTIC AND EGG PRODUCTION

Sherwood, D. H., and T. T. Milby, 1954. Further tests with antibiotics for laying and breeding hens. Poultry Sci. 34: 1031-1033. Sizemore, J. R., R. J. Lillie, H. R. Bird and C. A. Denton, 1955a. Further studies on the influence of aureomycin in the chick diet upon subsequent reproductive performance of laying hens. Poultry Sci. 34: 432-435. Sizemore, J. R., R. J. Lillie and C. A. Denton, 1955b. Effect of vitamin Bi2 upon chick and laying house performance of New Hampshires. Poultry Sci. 34 : 1254. Sizemore, J. R., R. J. Lillie, C. A. Denton and H. R. Bird, 1953. Influence of aureomycin in the chick diet upon subsequent reproductive performance of laying hens. Poultry Sci. 32: 618-624. Snedecor, G. W., 1946. Statistical Methods Applied to Experiments in Agriculture and Biology. Iowa State College Press, Ames, Iowa. Sunde, M. L., J. G. Halpin and W. W. Cravens, 19S2. The effect of vitamin BJ2 supplements and antibiotic feed supplements on egg production and hatchability. Poultry Sci. 3 1 : 617-620. Waibel, P. E., M. L. Sunde and W. W. Cravens, 1952. Effect of addition of penicillin to the hen's ration on biotin and folic acid content of eggs. Poultry Sci. 3 1 : 621-624. White-Stevens, R., H. G. Zeibel and F. Smith, 1955. Effect of high level antibiotic feeding on production efficiency of laying and breeding chickens and turkeys. Poultry Sci. 34: 1228.

NEWS AND NOTES PURDUE NOTES Professor W. G. Shannon (B.S.—Queens, Belfast) is on leave from Loughry Agricultural College in North Ireland on a Kellog Foundation Fellowship. He is studying for the M.S. degree with a major in poultry products technology. F. J. Schmidt (B.S., Dkfm.—Vienna) is Graduate Research Assistant in poultry products technology. R. M. Leach (B.S.—Maine, M.S.—Purdue) has accepted a position as Graduate Assistant in poultry nutrition at Cornell University. J. C. Rogler (B.S.—Rhode Island, M.S.—Purdue) has returned from military service to his position as Graduate Research Assistant in poultry nutrition. R. H. Mayo (B.S.—Oklahoma, M.S.—Purdue) has completed two years as Ralston-Purina Fellow in poultry nutrition. He has accepted an appoint-

ment as Graduate Research Assistant in animal nutrition. D. F. Bray (B.S.A.—Toronto) has been appointed Graduate Research Assistant in poultry genetics. ILLINOIS NOTES Dr. G. F. Godfrey has been appointed Executive Director of the Honegger Hatchery operations at Forrest, 111. He replaces A. P. Loomis who retired on June 30th, after 14 years of service. Dr. Godfrey has been with the Honegger organization since June, 1955. Prior to this, he was on the staff of Oklahoma A and M College. P.E.N.B. NOTES Mrs. Suzanne Armstrong has been appointed New York Editor for the Poultry and Egg National Board at its Eastern Branch office.

(Continued on page 792)

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Halbrook, E. R., and A. F. Beeckler, 1951. The value of a vitamin Bi2-antibiotic supplement when added to poultry mash mixtures containing an animal protein concentrate. Poultry Sci. 30:916. Heywang, B. W., 1954. High levels of antibiotics in the diets of laying chickens. Poultry Sci. 34: 10S9. Jacobs, R. L., J. F. Elam and J. R. Couch, 1955. Effect of administering antibiotics upon egg production, growth and antibiotic-resistant microorganisms. Poultry Sci. 34: 1232. Lillie, R. J., and H. R. Bird, 1952. Effect of antibiotic supplements upon hatchability and upon growth and viability of progeny. Poultry Sci. 31:513-518. Lillie, R. J., and J. R. Sizemore, 1954. Effect of antibiotic on egg production of New Hampshires. Poultry Sci. 33: 427-429. Petersen, C. F., and C. E. Lampman, 1952. Value of antibiotic in rations for egg production. Poultry Sci. 3 1 : 1067-1069. Petersen, C. F., C. E. Lampman and A. C. Wiese, 1952. Use of an APF supplement with and without fish meal for egg production and hatchability. Poultry Sci. 3 1 : 132-136. Reid, B. L., J. H. Quisenberry and J. R. Couch, 1951. Aureomycin, vitamin Bi2, methionine and level of protein in mature fowl nutrition. Poultry Sci. 30: 935-936. Sherwood, D. H., and T. T. Milby, 1953. Antibiotics in the ration of laying and breeding hens. Poultry Sci. 32: 932.

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