1328 E. J. DAY AND B. C. DILWOETH for calcium:phosphorus ratios shows that toe ash was lowest for the birds receiving the rations containing the most narrow calcium:phosphorus ratio. Again, this observation is in agreement with the data reported by Nelson et al. (11). SUMMARY Evidence was presented which indicates that turkey growing rations containing.6% (approximately.33% available) total phosphorus are adequate from 9-16 weeks of age, with dietary calcium phosphorus ratios of 2:1, 1.5:1, or 1:1. During the 17-24 week growth period, rations containing as little as.45% total phosphorus (approximately.21% available) were found to be adequate, as measured by growth, feed utilization and toe ash, with dietary calcium: phosphorus ratios of 2:1, 1.5:1, and 1:1. Although no significant differences were found due to the type of COMMERCIAL hatcherymen have observed that fertile from pullets just starting to lay do not hatch well and that mortality rate in the chicks which do hatch is abnormally high. Sunde and Bird (1959) observed that both fertility and hatchability of fertile was much lower in from pullets just starting to lay than it was in laid six weeks later. Scientific Paper No. 2182, Washington Agricultural Experiment Stations, Pullman. Project No. 1582. ration fed, growth and feed utilization tended to be better for the birds fed the rations containing a narrow ratio between calcium and phosphorus and the lower phosphorus levels; whereas, the opposite trend was observed for percent toe ash. REFERENCES Duncan, D. B., 1955. Multiple range and multiple F tests. Biometrics, 11: 1-42. Evans, R. J., and J. S. Carver, 14. The toe ash as a measure of calcification in chicks. Poultry Sci. 23 : 351-352. Jones, M. L., C. W. Deyoe, R. E. Davies and J. R. Couch, 11. Effect of phosphorus on growth and hock disorders of turkeys 8-23 weeks of age. Poultry Sci. 4: 1419. Nelson, F. E., L. S. Jensen and J. McGinnis, 11. Requirement of developing turkeys for calcium and phosphorus. Poultry Sci. 4: 47-411. Sullivan, T. W., 1. An estimate of the phosphorus requirement of Broad Breasted Bronze turkeys 8-2 weeks of age. Poultry Sci. 39: 1321-1327. Effect of Calcium Level of the Developing and Laying Ration on Hatchability of Eggs and on Viability and Growth Rate of Progeny of Young Pullets 1 LAWRENCE R. BERG, GORDON E. BEARSE AND LOUIS H. MERRILL Washington State University, Western Washington Experiment Station, Puyallup (Received for publication January 19, 12) Much of the embryonic mortality in the first laid occurred during the first week of incubation. Such dietary factors as vitamin levels, protein levels, antibiotic levels and vegetable vs. animal protein were found to have no effect on improving the hatchability of from young breeder hens. This paper will present evidence that level of calcium in the laying diet may affect hatchability of and growth and viability of chicks from pullets just starting to lay. Downloaded from http://ps.oxfordjournals.org/ at Penn State University (Paterno Lib) on March 6, 216
EFFECT OF CALCIUM ON HATCHABILITY 1329 EXPERIMENTAL The data to be presented were secured as part of a study designed to determine the effect of dietary calcium level during the developing period on subsequent laying house performance. Twenty-four groups of 7 White Leghorn pullets each were started on test when eight weeks old. All groups were housed in similar 1 X 12 ft. pens located in one windowless, fan ventilated house. Daily photoperiod for the pullets started at 16 hours at 8 weeks and was decreased by weekly decrement to eight hours by 21 weeks. Eight groups of pullets received each of the three developing diets shown in Table 1. These calculated to contain.5, 1. and % calcium. At 21 weeks of age the groups of birds were moved intact to a laying house containing twenty-four 1 X 2 ft. pens. This house was equipped with windows and employed natural ventilation. Light was immediately increased to a minimum of 13 hours per day. Two of the eight groups Ingredient Ground yellow corn Ground milo Ground barley Dehydrated grass Soybean oil meal (44% protein) Herring fish meal Dicalcium phosphate Tricalcium phosphate Limestone flour Salt Inedible tallow Calculated analysis Protein, % Calcium, % Phosphorus, % TABLE 1.Percentage composition of rations 1 31.68 2.5 11.58 2.5 1.27.17 15..5.6 Developer 1 2 3.1 2.5 11.87 2.5 1.29 1.44 15. 1..6 3 26.93 2.5 12.47 2.5 1.32 3. 15..6 fed each of the developing rations were fed one of the four laying diets shown in Table 1. These were calculated to contain,, and % calcium. Hatch 1Procedure. Four White Leghorn males were introduced into one pen of each of the 12 experimental treatments at 21 weeks of age. When all of the groups were laying approximately 3%, were saved for hatchability studies. The were weighed and divided into two weight classifications. One group contained weighing from 42-47 grams each, the other 48-54 grams each. Fifty were set from each weight classification from each pen. One hundred from a control group of hens were incubated for comparison. The control were obtained from hens of the same breeding which were two months older than the experimental birds. These hens had been fed the % calcium experimental diet for the same period as the experimental birds. All were candled at 7 and 19 1 27. 3. 8. 5. 1.69 3.4 1. 15..7 2 24.84 3. 8.61 5. 1.72 4.33 2.2 15..7 2 3 21.71 3. 9.22 5. 1.76 5.61 3.4 15..7 4 18.57 3. 9.83 5. 1.8 6.9 4.6 15..7 Chick' 32.41 3 1.5 25.6 5. 1.36.83 3. 21. 1..7 Downloaded from http://ps.oxfordjournals.org/ at Penn State University (Paterno Lib) on March 6, 216 1 Added per pound of diet: 62 mg. MnSOi; 2 I.C.U. vitamin D 3 ; U.S.P. units vitamin A; 1. mg. riboflavin; 57 mg. nicarbazin; 57 mg. B.H.T. 2 Added per pound of diet: 62 mg. MnS 4 ; 35 I.C.U. vitamin D 3 ; 15 U.S.P. units vitamin A; 1.5 mg. riboflavin; 1. mg. calcium pantothenate; 57 mg. B.H.T.; 27 mg. sulfaquinoxaline. 3 Added per pound of diet: 17 mg. methionine; 62 mg. MnS 4 ; 2 I.C.U. vitamin D S ; 125 U.S.P. units vitamin A; 1.1 mg. riboflavin; 1.8 mg. calcium pantothenate; 3. mg. niacin; 1. meg. vitamin B, 2 ; 1. mg. menadione sodium bisulfite; 57 mg. choline chloride; 57 mg. B.H.T.; 2.5 mg. zinc bacitracin.
133 L. R. BERG, G. E. BEAESE AND L. H. MERRILL of incubation. The apparently infertile were broken out and fertility determined macroscopically. Chick mortality and growth studies were conducted by randomly selecting 36 chicks from each egg weight class of each dietary treatment. The 36 chicks were distributed into three groups of 12 and placed in units of electrically heated battery brooders. In those instances where 36 chicks were not hatched from a treatment, all available were used in the chick test. A commercial type chick starter diet was used, Table 1. Mortality and growth rate were determined over a two week period. When the chicks were weighed at two weeks of age an abnormal wing feather development was TABLE 2.Effect % Ca in diet Develop..5 1. Summary 3 Developer.5%Ca 1.% Ca % Ca % Ca % Ca % Ca % Ca noted in many of the chicks. The nature of the abnormality, and a method for scoring such, are shown in Figure 1. Results. Fertility was not affected by the calcium level of the developing or laying ration, Table 2. Average fertility was very good, being about % for the smaller and % for the larger. Hatchability of fertile was not affected by level of calcium in the developing ration, Table 2. However hatchability of the smaller (42-47 g.) decreased as the level of calcium in the laying ration increased, the hatchability from the four respective increasing levels of calcium being 85.6, 83.6, 71.4 and 68.3%. Hatchability with the two lower levels of calcium, of calcium level of developing and laying ration on fertility and hatchability First hatch-set 3/9/61' Second hatch-set 4/5/61 2 42-47 gram 48-54 gram 46-5 gram 51-56 gram % % hatch fertile of fertile 9 95 93 95 87.5 83.7 78.3 66.7 85.7 89.6 66.7 66. 83.7 77.6 7.8 72.3 78.6 77.2 76.2 85.6 83.6 71.4 68.3 % % hatch fertile of fertile 92 95 81.6 87.8 86.4 82.6 89.6. 81.3 84. 9 84. 95.7 77.6 84.6 87.8 86.7 87.1 89.3 87.8 81.4 % % hatch fertile of fertile.9. 83. 89.8 9 9 9 88. 75. 87.5 84. 84. 92.2 9.5 82.6 88.3 91.8 8 87.3 % % hatch fertile of fertile 89.8 88.. 84. 9 89.8.. 79.6. 86. 86. 9 92.5 86.4 86.5 9.6 9 88.7 Downloaded from http://ps.oxfordjournals.org/ at Penn State University (Paterno Lib) on March 6, 216 1 About 3% lay. 2 In full production. 3 Eggs from control hens in the first hatch, which were of same breeding but two months older and fed the same % Ca diet, were % fertile and 85.1% of fertile hatched.
EFFECT OF CALCIUM ON HATCHABILITY 1331 and %, was markedly better than that on the two higher levels, and %. With the larger (48-54 g.) hatchability was depressed only in the from hens fed the highest level of calcium. The from the control hens were % fertile and 85.1% of the fertile hatched. Distribution of the embryonic mortality by periods -7, 7-18 and 18-21 of incubation is shown in Table 3. Among the three groups receiving or Z.25 r / ( calcium, no definite pattern of embryonic mortality was apparent. However, with the three groups receiving % calcium, peak embryonic mortality among the smaller occurred during the first seven. This is in contrast to those from the % calcium diet where peak embryonic mortality occurred during the 18-21 day period. Among the larger the only trend in embryonic mortality was in the from the % calcium where again mortality was greatest during the 18-21 day period. FIG. 1. Scoring system for abnormal feather development. Level of calcium in the developing ration had no consistent effect on early chick mortality, growth rate or feather development, Table 4. Chick mortality increased markedly as the amount of calcium in the laying ration increased. This was true for both egg size groupings from which the chicks were hatched, although mortality was less in the chicks from the larger with each laying ration. In chicks from the smaller, mortality was, 7.4, 18.9 and 3.9% for the four increasing levels of calcium in the laying ration, and.9, 3.7, 1 and 23.3% for chicks from the larger. Chick weight decreased with increasing amounts of calcium in the hen diet. The average two week weights of the chicks hatched from small from the four increasing levels of calcium were 17,, and 95 grams respectively. The chicks hatched from the larger were larger but the effect of the maternal diet was of Downloaded from http://ps.oxfordjournals.org/ at Penn State University (Paterno Lib) on March 6, 216
1332 L. R. BERG, G. E. BEARSE AND L. H. MERRILL TABLE 3.Time of embryonic mortality as affected by level of calcium in the developing and laying ration, hatch 1 % Ca in diet % Mortality 42-47 g. % Mortality 48-54 g. Develop..5 1. Summary Developer.5%Ca 1.% Ca % Ca % Ca % Ca % Ca % Ca -7 1.4 6.1 14.9 1.2 15.6 1.6 12.2 16.7 8.5 9.4 1.7 1.4 8.2 8.2 15.7 8.5 7-18 6.7 6.4 8.2 4.2 3.8.7 3.4 4.3 4.9 the same nature as with chicks from the smaller. The amount of abnormal feather development increased as the level of calcium in the laying ration increased. The degree of abnormality was equally as great in the chicks hatched from the two egg weight classifications. Chicks hatched from laid by the control hens receiving a high level of calcium (%) had no mortality during the first week and practically no evidence of abnormal feather development. Hatch 2Procedure. The for the second hatch were saved and incubated four weeks after the first hatch. At this time the pullets were at near peak production (8% lay). Fifty from each of two weight classifications, 46-5 grams and 51-56 grams, were set from each of the 18-21 6.1 4.3 2.8 11.1 17. 1.2 8.3 17. 8.3 8.6 8.9 5.5 7.9 18.3-7 1.2 4.5 8.7 4.2 1.4 4. 8.2 6.9 5.5 6.1 5.7 7-18 4.5 4.2 1 2.6 4.6 4.7 2.9 18-21 6.1 1.2 4.5 8.7 1 4. 1.2 7.4 5.6 3.6 5.4 3.6 1.3 12 treatments. Chick studies were conducted as with the chicks from hatch 1. Results. In contrast to the results of the first hatch, high levels of calcium in the laying ration did not affect hatchability, Table 2. Chick mortality was very low, with no effect of the calcium level of the maternal diet being apparent, Table 5. Likewise, growth rate of the chicks was not affected by the calcium content of the hen diet. Although the abnormal feather score of the chicks tended to increase with increasing level of calcium in the hen diet, the degree of abnormal feathering was not nearly as great as observed with the first hatch. DISCUSSION The findings of this study may partially explain the observed poor hatchability of Downloaded from http://ps.oxfordjournals.org/ at Penn State University (Paterno Lib) on March 6, 216
EFFECT OF CALCIUM ON HATCHABILITY 1333 TABLE 4.Effect of calcium level of developing and laying hen diets on mortality, growth and feathering of progeny, hatch 1 Devel..5 1. Summary 3 Developer.5% Ca 1.% Ca % Ca % Ca % Ca % Ca % Ca % Ca in diet 1st week mortality - 42^7 g. 1 48-54 g. 1 % % 16.7 14.7 23.3 5.6 18.7 4 23.3 29.5 14.4 16.8 13.9 7.4 18.9 3.9 2 13.9 3.5 5.6 19.5 19.5 6.4 15.7 15.8.9 3.7 1 23.3 2 week wts., g. 42-47 g.i 48-54 g. 1 17 93 17 12 93 16 14 88 17 95 11 15 18 15 115 111 12 12 13 16 111 13 12 1 Weight of from which chicks hatched. 2 See Figure 1 for description of feather scores. 3 ControlsNo mortality, average weight 127 grams, feather score.6. Feather score 2 42-47 g. 1 48-54 g. 1.68 1.13 1.71 2.39 1.15 1.87 1.37.51.86 1.9 1.65 1.39 1.2 1.3.53 1.5 1.56 1,68.52 1.4 1.83 1.78.25 1.17 1.92 1.45.53 1.2 1.35 3 1.29 1.2.43 1.14 1.7 from young breeders observed by hatcherymen and reported by Sunde and Bird (1959). The results suggest that poor hatchability and viability of chicks related to pullets just entering production may be the result of high levels of calcium in the laying ration. That high calcium level of the diet can explain most or all of the reduced hatchability of from newly maturing pullets is open to question, however, because in the studies of Sunde and Bird (1959) fertility as well as hatchability was reduced in first laid whereas in the present studies high dietary calcium had no effect on fertility of. The adverse effects of the high levels of calcium may be mediated through interference with zinc metabolism. The abnormal feather development observed in the chicks from the hens on the high calcium level was identical to that described by Young et al. (1958) as a symptom of zinc deficiency. That the reduced growth rate with increasing calcium levels may be a reflection of decreasing amounts of available zinc is suggested by the results of Young et al. (1958) and of Kienholz et al. (11). The results of Kienholz et al. (11) also showed that insufficient zinc in the maternal diet resulted in high chick mortality, similar to that obtained in the present study, even though the chicks were fed commercial diets capable of supporting good chick growth. Downloaded from http://ps.oxfordjournals.org/ at Penn State University (Paterno Lib) on March 6, 216
1334 L. R. BERG, G. E. BEARSE AND L. H. MERRILL TABLE 5.Effect of calcium level of developing and laying hen diets < mortality, growth and feathering of progeny, hatch 2 % Ca in diet.5 1. Summary Developer.5% Ca 1.% Ca % Ca % Ca % Ca % Ca % Ca 1st week mortality 46-5 g. 1 % 2.3 2.3 8.6 2.4 2.3 1.8.6 1.5 3.8 1.6 51-56 g. 1 % 4.2 2.4 6.5 5.2 1.1 1.8 1.7.8 3.6 1.4 1 Weight of from which chicks hatched. 2 See Figure 1 for description of feather scores. It has been shown by several investigators, as reviewed by Forbes (1), that high levels of dietary calcium will interfere with zinc nutrition in swine and poultry. Kienholz et al. (11) also found that high levels of dietary calcium (4.%) aggravated a zinc deficiency in adult hens. If insufficient available zinc with the higher calcium levels was responsible for the results obtained in the present study, the indications are that the requirement for zinc must be considerably higher at the onset of reproduction than at other stages of the life of the bird. The reduced effects of the high calcium levels on the larger, which are assumed to be laid at a greater time after the onset of egg production, and on the laid when the birds 2 week wts., g. 46-5 g. 1 18 17 111 15 16 12 18 14 12 18 14 16 18 15 15 15 16 18 15 51-56 g. 1 113 113 116 111 116 115 116 112 112 11 113 115 112 112 Featb er score 2 46-5 g. 1.2.22.7.9.18.85.46.22.24.61.53.36.4.4.17.24.56.56 51-56 g. 1.23.18.48.52.13.4.75.1.17.52.54.35.35.38.18.37.59.31 were in full lay both suggest a higher requirement during the early stages of egg production. Based on the zinc values of feed ingredients shown by Norris and Zeigler (1959), the laying ration with the highest level of calcium in the present study had a calculated zinc content of 6-65 p.p.m. The chick diet contained approximately 8 p.p.m. of zinc. According to the findings of Kienholz et al. (11), 65 p.p.m. of zinc in the laying ration should have been sufficient to permit normal embryonic development and growth and viability of chicks. In the present test, this quantity was sufficient after the birds had been in lay for a short time but apparently was not at the onset of production. If further tests Downloaded from http://ps.oxfordjournals.org/ at Penn State University (Paterno Lib) on March 6, 216
EFFECT OF CALCIUM ON HATCHABILITY 1335 show conclusively that the poor hatchability and livability of chicks from first laid are due to zinc insufficiency then it will be of interest to determine what metabolic functions associated with developing sexual maturity require more zinc than is normally required for growth and reproduction. One can speculate that zinc deficiency might possibly be the result of a sudden increased production of carbonic anhydrase, a zinc-containing enzyme involved in egg shell formation. Because zinc is a component of several other enzymes involved in various metabolic functions, it is possible that the "stress" of the physiological changes associated with sexual maturity increases the requirement for these enzymes, and thus for zinc. After the "stress" of attaining sexual maturity has passed, the requirements could diminish. Evidence that normal egg formation patterns are not present in many pullets just entering production is suggested by the number of shell-less and double yolked produced. It is of interest that the amount of calcium in the developing diet from 8-21 weeks of age had no effect on the reproductive criteria studied, even though the highest level of calcium used, 2%, was much higher than the accepted requirement for the developing period from 8-18 weeks, National Research Council (1). In the present study the pullets had received the laying rations for approximately three weeks before the for the studies were saved for incubation. Thus it is apparent that the effect of level of calcium in the diet is mediated during the period just prior to or at the onset of production and is not influenced by calcium level of the diet prior to this period. SUMMARY White Leghorn pullets fed diets containing.5, 1. and % calcium from 8-21 weeks of age were subsequently fed laying rations containing,, and % calcium. After being on the laying rations for approximately three weeks, or at 3% lay, were saved for incubation. Fertility of was high and not affected by level of calcium in the developing or laying diet. Hatchability of fertile decreased and mortality among the chicks increased as level of calcium in the laying ration increased. Higher levels of calcium in the laying ration also resulted in decreasing growth rate and in increasing degree of abnormal wing feather development among the progeny. The abnormal wing feather development was similar to that described as a symptom of zinc deficiency. With produced four weeks after 3% lay was attained, or at peak lay, there was no effect of calcium level of the laying diet on hatchability of or on viability or growth rate of progeny. Calcium level of the developing diet had no effect on any of the experimental criteria studied. REFERENCES Forbes, R. M., 1. Nutritional interactions of zinc and calcium. Federation Proc. 19: 643. Kienholz, E. W., D. E. Turk, M. L. Sunde and W. G. Hoekstra, 11. Effect of zinc deficiency in the diets of hens. J. Nutrition, 75: 211-221. National Research Council, 1. Nutrient requirements for domestic animals. No. 1. Nutrient requirements for poultry. Norris, L. C, and T. R. Zeigler, 1959. Some results of studies on the zinc requirement of chicks. Cornell Feed Service No. 52. Sunde, M. L., and H. R. Bird, 1959. The effect of pullet maturity on fertility and hatchability of. Poultry Sci. 38: 272-279. Young, R. J., H. M. Edwards, Jr. and M. B. Gillis, 1958. Studies on zinc in poultry nutrition. 2. Zinc requirement and deficiency symptoms of chicks. Poultry Sci. 37: 1-117. Downloaded from http://ps.oxfordjournals.org/ at Penn State University (Paterno Lib) on March 6, 216