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Effect of Single Cereal Grains Upon the Hatchability of Eggs and Subsequent Growth of Chicks
y
VELAN D. CALL* AND H. L. WILCKE Iowa Agricultural Experiment Station, Ames, Iowa Received for publications December 27, 1938)
T
HE problem of securing eggs that hatch well is of fundamental importance to the entire poultry industry. It is a problem of great concern to the hatcherymen, who anticipate that 35 percent of the eggs set will not hatch. Likewise the problem of fertility and hatchability is of outstanding scientific interest. The biologist is concerned with the causes of embryonic development and death. The fact that hatchability of eggs may be affected by the feed given the breeding stock has been demonstrated repeatedly in a large number of experiments. However, most of the investigations have been made with proteins, vitamins, and minerals. Only occasionally has there been incidental mention of the role that the various grains might have in relationship to hatchability and fertility. Observations have been made which tend to indicate that various nutritional elements ingested by parent stock have an influence on the development of the offspring. The insufficiency or the excess of proteins, vitamins, and minerals fed the parental stock has played considerable part in the subsequent development of the progeny. This study was undertaken in an at* M r . V. D. Call was formerly a graduate student in the Department of Poultry Husbandry at Iowa State College. Journal Paper No. J603 of the Iowa Agricultural Experiment Station. Project No. S13.
tempt to determine the effect of single grains in the ration of the breeders upon the fertility and hatchability of eggs, and the effect that these rations fed to the breeders might have upon the subsequent growth of the chicks hatched from their eggs. REVIEW OF LITERATURE Ballantyne (1924) reported that hens fed corn as a scratch feed laid eggs that gave a higher fertility than hens fed no corn. Penquite, Thompson, and Naylor (1927), however, found that grains did not affect the fertility. This is also verified by Morgan (1930). Penquite et al. (1927) found that hatchability of fertile eggs produced by hens fed a mixed grain ration was no better than that of the eggs produced by hens on single grains for scratch, but the egg production was increased considerably. The birds that received only wheat as a scratch grain were weak and emaciated throughout the experiment and the mortality was high. Payne (1934) showed that the milo, kafir, wheat, and corn fed might affect the hatchability of the eggs produced. Halpin and Hays (1934) reported that eggs from birds fed a wheat ration gave IS percent higher hatch than those on a corn ration. Barley and oats gave better hatchability than corn. They also reported no significant difference between barley and wheat as
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Effect of Single Cereal Grains Upon the Hatchability of Eggs and Subsequent Growth of Chicks
EFFECT OF SINGLE CEREAL GRAINS UPON HATCHABILITY AND GROWTH
EXPERIMENTAL
Method of Procedure Four pens of yearling Single Comb White Leghorn birds were used in this study. Each pen consisted of 40 or more females and the appropriate number of males. The birds were all of the Iowa State College strain. The hens had finished onehalf year of laying previously but they were in good flesh and in good health at the time the experiment was initiated. They were distributed at random in the various pens. The males were selected from a group of spring hatched Single Comb White Leghorns cockerels that had been reserved as breeders for the regular college flock. No selection was made as to the initial pen into which they were placed. These cockerels were alternated in pens after each hatch so that any individual influence they might have on this study would be distributed throughout the various pens. When one male became weak or died he was replaced by another cockerel from the same group from which the original birds were selected. If death reduced the number of hens to less than 10 to one male, a cockerel was removed and adjustments were made to keep the ratio as nearly IS to one as possible. All pens were started in semi-monitor laying houses and remained there until just after the third setting was made, when they were placed together in the same house. All the birds were kept in confinement throughout the experiment. All-night lights were used and the houses were unheated. Rations Fed the Breeding Stock The objective desired in calculating the rations fed lots 1, 3, and 4 was to keep all factors as nearly equal as could be estimated, the only variation being in the
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far as hatchability was concerned. Smith (1935) also found that barley and wheat produced very similar results in regard to the hatchability of the eggs. The pullets fed these grains produced eggs with greater hatching power than those fed corn or oat groats, but somewhat less than the eggs from the birds fed a mixture of all four grains. These birds were reared on diets made up with the same grains used in the laying tests. These results did not hold true when the pullets were reared under range conditions, presumably fed a ration made up of a mixture of grains, and changed to the single cereal grain diets at maturity. Smith felt "that the adaptability of the ration and the 'survival of the fit' are factors worthy of some consideration" in explaining his results, since there was a heavy mortality in the wheat pen during the growing period. As a result of an extensive survey of literature Crampton (1936), placing barley at 100, gave the relative values of the various grains for hatchability as follows: barley 100, corn 109, wheat 114, and oats 97. In his compilation of literature recording the factors affecting hatchability, Landauer (1937) concluded that nutritional factors influenced the hatching quality of the eggs by way of the organism of the female, but there was no evidence which seemed to indicate that nutritional deficiencies of the sire affected the hatchability of the eggs fertilized by them. Penquite and his co-workers (1927) found that stock fed white corn produced inferior chicks, and that these chicks did not grow well even when transferred to an adequate balanced ration. The other chicks produced from parents fed wheat and barley were vigorous and sturdy. The birds from the pen fed mixed grains produced what appeared to be the healthiest and most thrifty chicks of any of the pens.
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VELAN D. CALL AND H. L. WILCKE
plied in all pens in sufficient quantities. The estimated chemical composition of the mash mixtures used is presented in Table 2. TABLE 2.—Estimated composition of the various mash rations Pen No.
Protein
Ash
1 2 9A 9B
14.25 19.11 14.23 14.23
7.98 9.53 7.50 8.93
Calcium Phosphorus 2.58 2.70 2.31 2.35
.85 1.01 .82 .81
These rations meet the protein requirements for good hatchability as given by Heiman, Carver, and St. John (1936). The mineral content was about equal in all experimental pens and sufficient for good hatchability. Pen 2 received in addition to the mash an equal amount of scratch grain, consisting of two parts of yellow corn and one part of whole oats. Consequently, the total protein content of the ration for pen 2 was practically the same as that of the birds in other pens. After the hens had been on these experimental feeds for five months, they were all changed to the same ration received by pen 2, in order to gain some information as to whether the effects of these
TABLE 1.—Rations fed breeding stock Ingredients Ground yellow corn Ground wheat Ground oats Dried buttermilk Wheat bran Wheat middlings Alfalfa leaf meal Meat and bone meal Corn gluten meal Soybean oil meal Liver meal Oyster shell Bone meal Fish meal Salt Cod liver oil cone. Total
Pen 1
Pen 2
77.5
20.0
Pen9A
Pen 9B
82.0 10.0
1.0 3.0 3.0 4.5 1.0 .25 100.25
10.0
82.0 10.0
1.0 3.0 3.0
1.0 3.0 3.0
1.0 .25
1.0 .25
1.0 .25
100.25
100.25
100.25
27.0 5.0 10.0 10.0 7.0 8.0 2.0 3.0 3.0 3.0 1.0
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type of grain used. The birds in pens 1, 3, and 4 were fed all-mash rations, while pen 2 was fed a mash and scratch ration. This pen was included as a control pen since the results from this lot were representative of those secured from this stock when fed a standard ration. These rations, it will be observed, were supplied with adequate amounts of vitamins A, D, flavin, and E, which are necessary for hatchability. They all contain more than the minimum requirements for vitamin A, according to the standards set by Sherwood and Fraps (1936), and also those indicated by Bearse and Miller (1937). Likewise, the vitamin D units in all pens were considerably above the requirements as given by Carver et al. (1934), and by Murphy, Hunter, and Knandel (1936). The flavin requirements necessary for good hatchability, as determined by Norris and his associates (1936), were met by using dried milk and dried liver meal. Nestler (1936) and others have suggested that there is another factor, not vitamin G, that is necessary for hatchability. It is found in dried buttermilk and is relatively abundant in dried liver meal. If this be the case, this factor was also sup-
EFFECT OF SINGLE CEREAL GRAINS UPON HATCHABILITY AND GROWTH
Selection and Incubation of Eggs The first eggs were kept for hatching after the hens had been on the ration for two weeks. They were set at intervals as follows: series 1, January 25; series 2, March 29; series 3, June 6; and series 4, July 7. All eggs, except those that were cracked, laid during the week previous to setting were incubated regardless of shape, size, or color. It was felt that this was desirable to provide a representative sample of the eggs produced. The number of eggs set from each pen at different times varied greatly. All the eggs were placed on wire trays in a cool egg room and were not turned prior to incubation. When one week's eggs had been assembled they were placed in the same incubator. The machine used was a Mammoth, forced-draft, all-electric type. On the eighteenth day they were transferred to a separate hatcher. After incubation for seven days, the eggs were candled and those showing dead germs were removed. All eggs which appeared clear before the candling lamp were classed as infertiles and were removed at this time. The next candling was done on the eighteenth day, and the final classification of dead embryos was made on the twenty-second day. All chicks, that were able to free themselves from the shell were termed hatched and were placed in the brooders, regardless of their vigor or physical condition. The chicks in series 1 and series 3 were weighed at two-week intervals. Those in
series 2 were weighed weekly for the first six weeks and bi-weekly thereafter. Prior to each weighing the chicks were deprived of feed for approximately six hours. It was felt that the weights thus obtained more nearly represented the actual weight of the chicks than the weights with the digestive tract full of feed. All the chicks hatched from the eggs collected from the various pens received the same feed, which consisted of the college chick ration. Growth was measured by means of weight and it was the only criterion used in this part of the study. RESULTS AND DISCUSSION
Observation of the effects on the breeding stock: Mortality oj Breeders The mortality.in all pens was high; especially was this true of pens-1, 2, and 9A. Table 3 shows the comparison of the death rate among the breeding stock in the various pens by months and total mortality. This table included only the records of hens that produced eggs in the experiment since all other records reported are based on data from only those birds. Mortality in the corn lot (pen 1) was the highest, being considerably above that of the control pen. It is difficult to draw any conclusions since the birds remaining in this pen at the end of the experiment were in excellent condition. The birds in the wheat lot (pen 9A) were quite unhealthy and were rather emaciated at the end of the feeding test. The litter was constantly wet which necessitated changing it much more often than the other pens. This was due to a diarrhea which developed within a few days after the birds were put on a whole wheat ration, and continued until they were changed to a ration of mixed grains. The reasons for
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rations could be eliminated in a short period. This ration was fed for four weeks until the experiment was discontinued. Water was supplied fresh twice daily, and during the winter months was kept from freezing by means of submerged electric heating devices.
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VELAN D. CALL AND H. L. WILCKE TABLE 3.—Average egg production and mortality of breeders laying eggs during the months oj
January to May Inclusive Pen No.
Jan.
Feb.
Mar.
April
May
Total Average per Month Mortality
Percent Mortality
No. of birds No. Dead Production
28 0 15.1
25 3 11.4
23 2 14.8
18 5 12.3
15 3 17.5
21.8 2.6 14.1
13
46.4
2
No. of birds No. Dead Production
32 1 17.0
29 2 13.2
27 2 16.1
23 4 15.1
22 1 14.6
26.6 2.0 15.2
10
31.2
9A
No. of birds No. Dead Production
17 0 6.7
17 0 3.7
16 1 7.0
14 2 9.9
13 3 8.4
15.4 1.2 7.3
6
35.3
9B
No. of birds No. Dead Production
28 1 7.5
27 0 5.2
27 0 11.5
27 0 10.9
24 3 11.5
26.6 0.8 9.8
4
14.3
this condition is unknown. This physiological disturbance perhaps had a considerable effect on the mortality in this pen. The best viability, when all things were considered, was in the oat-fed lot (pen 9B). These birds were healthy and in excellent flesh at the completion of the experiment. This was the only group which seemed to show considerable deviation in mortality from that of the control pen. There is an indication from this study that oats in the ration might increase the viability of the breeders. Egg Production The average egg production was highest in the control pen fed mixed grains, yielding an average of 15.2 eggs per hen per month. The corn-fed birds with 14.1 eggs per hen was the only group which approached the production of pen 2. The production of the oat-fed group was considerably below that in pens 1 and 2. The production of the wheat-fed group was consistently low and was less than half that of the control pen, and about half that of the corn-fed group. The emaciated condition of the birds in this pen, due to diarrhea, was probably a causative factor in this low production.
Effects on Hatching Eggs Fertility In the first series, pen 1 was the only lot which gave even fair fertility (85.4 percent) of the eggs set. Pens 2 and 9B were somewhat lower with 59.2 and 47.7 percent, respectively (see Table 4). Pen 9A was extremely low (19.2 percent), and was the lowest fertility obtained with the eggs from any pen throughout the entire experiment. This might be explained by recalling that these birds were in a condition of excessive diarrhea and this physiological disturbance was inhibitory to proper mating. It will be remembered that the eggs used in this series were collected after the breeders had been fed the experimental feed for only two weeks and apparently the wheatfed birds had not at that time been able to adjust themselves to their new feed. The fertility in series 2 was considerably higher than in the previous one and if the pooled average is considered it was the best of the four series, pen 9A was the highest (95.0 percent) while pens 9B, 2, and 1 followed in descending order; however, all four pens gave good fertility of over 90 percent. In series 3 the fertility of all the pens was in the same order as the preceding
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1
EFFECT OF SINGLE CEREAL GRAINS UPON HATCHABILITY AND GROWTH
uation and placing the control pen at 100, the following table has been developed: TABLE 5.—Comparative value of grains fed to breeders in relationship to fertility of eggs produced Feed
Pen No.
Mixed Grain = 100 108 100 86 99
Corn Mixed grains Wheat Oats
1 2 9A 9B
Embryo Mortality
TABLE 4.—Percent fertility of eggs set Pens Series Pen 1
Pen 2
Pen9A
Pen 9B
I II III IV
85.4 91.0 73.5 88.0
59.2 92.9 80.4 100.0
19.2 95.0 91.7 89.5
47.7 93.4 89.5 79.0
Mean of Total
84.5
78.3
67.5
77.6
Percent hatckability of fertile eggs I II III IV
85.5 60.7 50.0 63.6
62.2 58.2 61.4 64.0
100.0 94.7 63.6 100.0
86.9 77.1 73.5 83.6
Mean of Total
69.2
63.3
90.4
79.8
When the mean of the total eggs set was considered the data presented in this study indicated that corn was superior to mixed grains for fertility. It appeared that wheat was superior to corn after the physiological adjustments had been made to the diet. By using Crampton's (1936) method of eval-
The relative time at which the embryos died should be considered in a study of hatchability. The dead embryos in series 1 were all examined and when they were found to be rather uniformly distributed throughout the period, it was considered adequate to concentrate them into groups of 7, 18, and 21 days as they appeared dead at the different times of candling. From the data in Table 6, it is apparent that wheat is superior to the other single cereals or to a ration of mixed grains for the production of viable embryos. Statistical Analysis of the Hatchability of the Eggs A statistical analysis showed there was a highly significant difference between the pens in series 1, 2, and 4, and a significant difference between the pens in series 3. It was also quite evident that the difference in the pooled data from the four series was highly significant. It is interesting to
TABLE 6.—Comparison of embryo mortality at different stages of development for the various pens
Pen No. 1 2 9A 9B
Embryo Mortality
Total Fertile Eggs 185 241 52 163
7 days
Total
21 days
18 days
No.
%
No.
%
No.
%
No.
%
20 22 2 7
10.8 9.1 5.8 4.2
13 27 0 5
7.0 11.2 0.0 3.0
24 42 2 21
13.0 17.8 3.8 12.9
57 91 5 33
30.8 37.7 9.6 20.2
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series. The reduction in pens 9A and 9B was not quite so acute as that in pens 1 and 2. After the third series the hens were taken off the experimental feeds and were fed mixed grains for four weeks prior to collecting eggs for series 4. The order of fertility (see Table 4) was somewhat changed in this series; pen 2 led with 100 percent, followed in descending order by pens 9A, 1, 3, and 9B.
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VELAN D. CALL AND H. L. WILCKE
to consider the possibilities that such may be the case. More extensive study and larger numbers of eggs are necessary to verify this assumption. Pen 9B differed significantly from pen 2. The figures as presented in Table 5 show that oats, as far as this study indicated, was superior to mixed grains and corn for the production of good hatching eggs. When the mean of the total fertile eggs hatched was considered the data presented in this study indicated that wheat was superior to the other single grains and also to mixed grain. These data did not agree in all detail with the results reviewed by Crampton (1936), but generally speaking they were quite comparable. This study was made using only one single cereal, while the studies reported by Crampton (1936) used the only grain as the chief source of grain fed. By placing the control pen (mixed grains) at 100, the following table has been developed: TABLE 7,-—Comparative value of grains fed to breeders in relationship to hatchability of eggs produced, with mixed grains placed at 100 Pen 1 2 9A 9B
Feed
Mixed Grains = 100
Corn Mixed grains Wheat Oats
111 100 152 125
Growth of Chicks The chicks hatched from the eggs of all the series had a rather uniform incubation weight. It was noted, however, that chicks from pens 9A and 9B appeared more vigorous than those of the other pens. In series 1 there was a significant difference between mean weights of chicks from the pens at four weeks of age due to the high weight attained by the wheat birds and the low weight of the corn birds. The small number of chicks were due to an outbreak of chick bronchitis in the
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note that these results were quite consistent throughout the entire four series. These series were analyzed to determine what pens were responsible for the differences between pens within a series. Chisquare was used for determining the comparison between pens within each series. It was not found necessary to make this comparison for all pens because some were so close it was obvious there was no difference. The hatchability of eggs from pen 2 was highly significantly different from the other three pens. No other differences between pens were significant. Although there was a difference of about 14.5 percent between pens 9A and 1, the difference was not significant because of the small number of eggs in pen 9A. All the pens with the exception of 9B showed a highly significant difference from 9A in the second series. The results of this hatch might be separated into two groups—9A and 9B, and 1 and 2—each group showing considerable difference from the other group, but between the two pens within each group there was a non-significant variation in relation to hatchability. In other words wheat and oats were comparable, as were corn and mixed grain. When the pooled data of the four series were used, the Chi-square value was highly significant. Although there was a difference of over 10 percent of the averages of pens 9A and 9B it was not statistically significant, but the former was highly significantly different from the other two pens. The above evidence indicates that wheat is superior to mixed grains or corn for good hatchability. This agrees quite favorably with the evidence produced by Smith (1935) and Crampton (1936). Regardless of the fact that there is no statistical evidence for believing that wheat is superior to oats for hatchability of eggs, the fact that wheat is consistently higher leads one
EFFECT OF SINGLE CEREAL GRAINS UPON HATCHABILITY AND GROWTH
weeks of age the only significant difference was between the sexes. The total mean weights of both males and females were considerably below that found in the other two series at the same age. About the time the feed for this series was mixed a shipment of poor cod liver oil was received and used in the ration. It was not discovered until later when certain lots of chicks at the station started to develop rickets. As soon as this difficulty was discovered and remedied growth proceeded normally. At the 10-week stage, as was expected, there was a highly significant difference in the weights of the males and females. This was not due to the feed but is normal of birds of this age regardless of the type of rations. There was also a significant
TABLE 8.—Weight of chicks 4 weeks
I
II
III
Females
Males
Series Pen
No.
Mean Weight Grams
No.
Mean Weight Grams
1 2 9A 9B
20 12 1 7
199.0 255.8 270.0 217.1
22 12 6 6
191.4 216.7 230.0 198.3
Total
40
212.0
42
201.4
1 2 9A 9B
12 20 4 20
168.3 159.0 182.5 167.0
18 24 12 17
158.6 151.9 162.1 155.4
Total
56
165.5
71
156.1 ,
1 2 9A 9B
6 17 3 11
198.0 204.5 216.0 239.6
7 15 4 10
185.0 193.6 218.0 215.1
Total
37
214.8
36
200.5
1 2 9A 9B
12 16 3 18
744.2 717.4 743.3 739.4
17 22 12 16
596.5 599.1 597.5 600.6
Total
49
733.6
67
595.5
'
10 Weeks IV
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brooder room where these birds were kept. They were held for a week after the infection was severe in other brooders in the same room. Quite a number of these birds died just a few days prior to the time they were four weeks of age. It is noted, however, that the growth rate for series 1 is the same as for series 3 and superior to series 2, indicating that the weight was not affected by the disease. Chicks from the mixed grains and oat pens were intermediate. Two analyses of weights were made of the chicks hatched in series 2, one at four weeks and the other at 10 weeks of age. The second study was made to determine whether the feed of the parent stock had any influence upon the weight of the progeny for a longer period of time. At four
315
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VELAN D. CALL AND H. L. WILCKE
SUMMARY Four lots of yearling hens were used in this experiment, and were at the beginning a rather uniform group. They were all kept under as nearly similar conditions of housing and management as possible. The variations of feed, as far as it was possible to estimate, occurred only in the grains fed. All were supplemented with similar sources of vitamins, proteins, and minerals. All eggs were handled and incubated under the same conditions. The chicks hatched were treated in a uniform manner. Mortality was high in all lots of breeders, but oats seemed to improve viability. Wheat fed as the only grain produced a diarrhea in adult birds and apparently was a contributing factor in high mortality. Egg production was markedly reduced in the wheat and oat pens. The production in the other pens was rather uniform, with corn being equal to mixed grains for e[g production. Fertility was not affected significantly by the different rations.
i
Hatchability was best with eggs from the wheat birds, followed by oats, with corn and mixed grains approximately equal. Hens fed wheat or oats rations produced chicks with more vigor than those from hens fed corn. Chicks hatched from eggs of the various pens showed some variation in weight at four weeks of age, but-net--at-~hatehing_. time or at 10 weeks.'It seems questionable ' if grains in the diet of the parental stock I have much effect upon the subsequent .; growth of chicks. ..„..—-""" LITERATURE CITED
Bearse, G. E. and M. W. Miller, 1937. The effect of varying levels of vitamin A in the hen ration on the vitamin A content of the egg yolk, on hatchability and on chick livability. Poul. Sci. 16:39-43. Canada, Dept. of Agr., 1924. Ont. Exp. Sta. Report of Supt. (S. Ballantine), pp. S2-S8. Carver, J. S., E. I. Robertson, D. Brazie, R. H. Johnson, and J. L. St. John, 1934. The vitamin D requirements of chickens. Wash. Agr. Exp. Sta. Bui. 299. Crampton, Earle W., 1936. The comparative feeding values for poultry of barley, oats, wheat, rye, and corn. Dominion of Canada National Research Council Rpt. 29. Halpin, J. G. and J. B. Hayes, 1934. Feeding for eggs. Wis. Univ., Col. of Agr., Ext. Cir. 141, 5th edition. Heiman, Victor, J. S. Carver, and J. L. St. John, 1936. The protein requirements of laying hens. Wash. Agr. Exp. Sta. Bui. 331. Landauer, Walter, 1937. The hatchability of chicken eggs as influenced by environment and heredity. Storrs Agr. Exp. Sta., Conn. State College. Bui. 216. Morgan, C. L., 1930. Poultry feeding experiments. III. Ground barley vs. ground yellow corn in the mash for layers and breeders. S. Car. Agr. Exp. Sta. Bui. 273. Murphy, R. R., J. E. Hunter, and H. S. Knandel, 1936. The vitamin D requirements of growing chicks and laying hens. Pa. Agr. Exp. Sta. Bui. 334. Nestler, R. B., R. C. Byerly, N. R. Ellis, and R. W. Titus. 1936. A new factor, not vitamin G, necessary for hatchability. Poul. Sci. IS :6770.
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variation between mean weights of pens at this age due to the chicks hatched from pen 9A, whereas the mean weights for both male and female chicks from the other pens were very uniform. In series 3 there were no significant variations between either sex or pens, indicating that this group was rather homogenous in weight at four weeks of age. It is of interest to note that the mean weights of both the males and females were the same in series 1 and 3. There was considerably less variation between the weights of the different lots in the females than in the males. Since the data are not consistent from series to series, it must be assumed from the data collected that grains fed to the breeding stock have no effect upon the subsequent growth of the chicks.
EFFECT OF SINGLE CEREAL GRAINS UPON HATCHABILITY AND GROWTH
the poultry ration. Okla. Agr. Exp. Sta. Bui. 166. Sherwood, R. M., and G. S. Fraps, 1936. The vitamin A requirements of hens for egg production. Texas Agr. Exp. Sta. Bui. 514. Smith, J. B., 1935. The cereal grains and their use in poultry nutrition. 1. Hatchability Studies. Sci. Agr. 16:73.
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Norris, L. C , H. S. Wilgus, A. T. Ringrose, Victor Heiman, and G. F. Heuser, 1936. The vitamin G requirement of poultry. New York (Cornell) Agr. Exp. Sta. Bui. 660. Payne, Loyal F., 1934. The comparative nutritional value of sorghum grains, corn, and wheat as poultry feeds. Kans. Agr. Exp. Sta. Bui. 268. Penquite, R., R. B. Thompson, and H. R. Naylor, 1927. The value of certain scratch grains in
317
VELAN D. CALL* AND H. L. WILCKE Iowa Agricultural Experiment Station, Ames, Iowa Received for publications December 27, 1938)
T
HE problem of securing eggs that hatch well is of fundamental importance to the entire poultry industry. It is a problem of great concern to the hatcherymen, who anticipate that 35 percent of the eggs set will not hatch. Likewise the problem of fertility and hatchability is of outstanding scientific interest. The biologist is concerned with the causes of embryonic development and death. The fact that hatchability of eggs may be affected by the feed given the breeding stock has been demonstrated repeatedly in a large number of experiments. However, most of the investigations have been made with proteins, vitamins, and minerals. Only occasionally has there been incidental mention of the role that the various grains might have in relationship to hatchability and fertility. Observations have been made which tend to indicate that various nutritional elements ingested by parent stock have an influence on the development of the offspring. The insufficiency or the excess of proteins, vitamins, and minerals fed the parental stock has played considerable part in the subsequent development of the progeny. This study was undertaken in an at* M r . V. D. Call was formerly a graduate student in the Department of Poultry Husbandry at Iowa State College. Journal Paper No. J603 of the Iowa Agricultural Experiment Station. Project No. S13.
tempt to determine the effect of single grains in the ration of the breeders upon the fertility and hatchability of eggs, and the effect that these rations fed to the breeders might have upon the subsequent growth of the chicks hatched from their eggs. REVIEW OF LITERATURE Ballantyne (1924) reported that hens fed corn as a scratch feed laid eggs that gave a higher fertility than hens fed no corn. Penquite, Thompson, and Naylor (1927), however, found that grains did not affect the fertility. This is also verified by Morgan (1930). Penquite et al. (1927) found that hatchability of fertile eggs produced by hens fed a mixed grain ration was no better than that of the eggs produced by hens on single grains for scratch, but the egg production was increased considerably. The birds that received only wheat as a scratch grain were weak and emaciated throughout the experiment and the mortality was high. Payne (1934) showed that the milo, kafir, wheat, and corn fed might affect the hatchability of the eggs produced. Halpin and Hays (1934) reported that eggs from birds fed a wheat ration gave IS percent higher hatch than those on a corn ration. Barley and oats gave better hatchability than corn. They also reported no significant difference between barley and wheat as
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Effect of Single Cereal Grains Upon the Hatchability of Eggs and Subsequent Growth of Chicks
EFFECT OF SINGLE CEREAL GRAINS UPON HATCHABILITY AND GROWTH
EXPERIMENTAL
Method of Procedure Four pens of yearling Single Comb White Leghorn birds were used in this study. Each pen consisted of 40 or more females and the appropriate number of males. The birds were all of the Iowa State College strain. The hens had finished onehalf year of laying previously but they were in good flesh and in good health at the time the experiment was initiated. They were distributed at random in the various pens. The males were selected from a group of spring hatched Single Comb White Leghorns cockerels that had been reserved as breeders for the regular college flock. No selection was made as to the initial pen into which they were placed. These cockerels were alternated in pens after each hatch so that any individual influence they might have on this study would be distributed throughout the various pens. When one male became weak or died he was replaced by another cockerel from the same group from which the original birds were selected. If death reduced the number of hens to less than 10 to one male, a cockerel was removed and adjustments were made to keep the ratio as nearly IS to one as possible. All pens were started in semi-monitor laying houses and remained there until just after the third setting was made, when they were placed together in the same house. All the birds were kept in confinement throughout the experiment. All-night lights were used and the houses were unheated. Rations Fed the Breeding Stock The objective desired in calculating the rations fed lots 1, 3, and 4 was to keep all factors as nearly equal as could be estimated, the only variation being in the
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far as hatchability was concerned. Smith (1935) also found that barley and wheat produced very similar results in regard to the hatchability of the eggs. The pullets fed these grains produced eggs with greater hatching power than those fed corn or oat groats, but somewhat less than the eggs from the birds fed a mixture of all four grains. These birds were reared on diets made up with the same grains used in the laying tests. These results did not hold true when the pullets were reared under range conditions, presumably fed a ration made up of a mixture of grains, and changed to the single cereal grain diets at maturity. Smith felt "that the adaptability of the ration and the 'survival of the fit' are factors worthy of some consideration" in explaining his results, since there was a heavy mortality in the wheat pen during the growing period. As a result of an extensive survey of literature Crampton (1936), placing barley at 100, gave the relative values of the various grains for hatchability as follows: barley 100, corn 109, wheat 114, and oats 97. In his compilation of literature recording the factors affecting hatchability, Landauer (1937) concluded that nutritional factors influenced the hatching quality of the eggs by way of the organism of the female, but there was no evidence which seemed to indicate that nutritional deficiencies of the sire affected the hatchability of the eggs fertilized by them. Penquite and his co-workers (1927) found that stock fed white corn produced inferior chicks, and that these chicks did not grow well even when transferred to an adequate balanced ration. The other chicks produced from parents fed wheat and barley were vigorous and sturdy. The birds from the pen fed mixed grains produced what appeared to be the healthiest and most thrifty chicks of any of the pens.
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VELAN D. CALL AND H. L. WILCKE
plied in all pens in sufficient quantities. The estimated chemical composition of the mash mixtures used is presented in Table 2. TABLE 2.—Estimated composition of the various mash rations Pen No.
Protein
Ash
1 2 9A 9B
14.25 19.11 14.23 14.23
7.98 9.53 7.50 8.93
Calcium Phosphorus 2.58 2.70 2.31 2.35
.85 1.01 .82 .81
These rations meet the protein requirements for good hatchability as given by Heiman, Carver, and St. John (1936). The mineral content was about equal in all experimental pens and sufficient for good hatchability. Pen 2 received in addition to the mash an equal amount of scratch grain, consisting of two parts of yellow corn and one part of whole oats. Consequently, the total protein content of the ration for pen 2 was practically the same as that of the birds in other pens. After the hens had been on these experimental feeds for five months, they were all changed to the same ration received by pen 2, in order to gain some information as to whether the effects of these
TABLE 1.—Rations fed breeding stock Ingredients Ground yellow corn Ground wheat Ground oats Dried buttermilk Wheat bran Wheat middlings Alfalfa leaf meal Meat and bone meal Corn gluten meal Soybean oil meal Liver meal Oyster shell Bone meal Fish meal Salt Cod liver oil cone. Total
Pen 1
Pen 2
77.5
20.0
Pen9A
Pen 9B
82.0 10.0
1.0 3.0 3.0 4.5 1.0 .25 100.25
10.0
82.0 10.0
1.0 3.0 3.0
1.0 3.0 3.0
1.0 .25
1.0 .25
1.0 .25
100.25
100.25
100.25
27.0 5.0 10.0 10.0 7.0 8.0 2.0 3.0 3.0 3.0 1.0
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type of grain used. The birds in pens 1, 3, and 4 were fed all-mash rations, while pen 2 was fed a mash and scratch ration. This pen was included as a control pen since the results from this lot were representative of those secured from this stock when fed a standard ration. These rations, it will be observed, were supplied with adequate amounts of vitamins A, D, flavin, and E, which are necessary for hatchability. They all contain more than the minimum requirements for vitamin A, according to the standards set by Sherwood and Fraps (1936), and also those indicated by Bearse and Miller (1937). Likewise, the vitamin D units in all pens were considerably above the requirements as given by Carver et al. (1934), and by Murphy, Hunter, and Knandel (1936). The flavin requirements necessary for good hatchability, as determined by Norris and his associates (1936), were met by using dried milk and dried liver meal. Nestler (1936) and others have suggested that there is another factor, not vitamin G, that is necessary for hatchability. It is found in dried buttermilk and is relatively abundant in dried liver meal. If this be the case, this factor was also sup-
EFFECT OF SINGLE CEREAL GRAINS UPON HATCHABILITY AND GROWTH
Selection and Incubation of Eggs The first eggs were kept for hatching after the hens had been on the ration for two weeks. They were set at intervals as follows: series 1, January 25; series 2, March 29; series 3, June 6; and series 4, July 7. All eggs, except those that were cracked, laid during the week previous to setting were incubated regardless of shape, size, or color. It was felt that this was desirable to provide a representative sample of the eggs produced. The number of eggs set from each pen at different times varied greatly. All the eggs were placed on wire trays in a cool egg room and were not turned prior to incubation. When one week's eggs had been assembled they were placed in the same incubator. The machine used was a Mammoth, forced-draft, all-electric type. On the eighteenth day they were transferred to a separate hatcher. After incubation for seven days, the eggs were candled and those showing dead germs were removed. All eggs which appeared clear before the candling lamp were classed as infertiles and were removed at this time. The next candling was done on the eighteenth day, and the final classification of dead embryos was made on the twenty-second day. All chicks, that were able to free themselves from the shell were termed hatched and were placed in the brooders, regardless of their vigor or physical condition. The chicks in series 1 and series 3 were weighed at two-week intervals. Those in
series 2 were weighed weekly for the first six weeks and bi-weekly thereafter. Prior to each weighing the chicks were deprived of feed for approximately six hours. It was felt that the weights thus obtained more nearly represented the actual weight of the chicks than the weights with the digestive tract full of feed. All the chicks hatched from the eggs collected from the various pens received the same feed, which consisted of the college chick ration. Growth was measured by means of weight and it was the only criterion used in this part of the study. RESULTS AND DISCUSSION
Observation of the effects on the breeding stock: Mortality oj Breeders The mortality.in all pens was high; especially was this true of pens-1, 2, and 9A. Table 3 shows the comparison of the death rate among the breeding stock in the various pens by months and total mortality. This table included only the records of hens that produced eggs in the experiment since all other records reported are based on data from only those birds. Mortality in the corn lot (pen 1) was the highest, being considerably above that of the control pen. It is difficult to draw any conclusions since the birds remaining in this pen at the end of the experiment were in excellent condition. The birds in the wheat lot (pen 9A) were quite unhealthy and were rather emaciated at the end of the feeding test. The litter was constantly wet which necessitated changing it much more often than the other pens. This was due to a diarrhea which developed within a few days after the birds were put on a whole wheat ration, and continued until they were changed to a ration of mixed grains. The reasons for
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rations could be eliminated in a short period. This ration was fed for four weeks until the experiment was discontinued. Water was supplied fresh twice daily, and during the winter months was kept from freezing by means of submerged electric heating devices.
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VELAN D. CALL AND H. L. WILCKE TABLE 3.—Average egg production and mortality of breeders laying eggs during the months oj
January to May Inclusive Pen No.
Jan.
Feb.
Mar.
April
May
Total Average per Month Mortality
Percent Mortality
No. of birds No. Dead Production
28 0 15.1
25 3 11.4
23 2 14.8
18 5 12.3
15 3 17.5
21.8 2.6 14.1
13
46.4
2
No. of birds No. Dead Production
32 1 17.0
29 2 13.2
27 2 16.1
23 4 15.1
22 1 14.6
26.6 2.0 15.2
10
31.2
9A
No. of birds No. Dead Production
17 0 6.7
17 0 3.7
16 1 7.0
14 2 9.9
13 3 8.4
15.4 1.2 7.3
6
35.3
9B
No. of birds No. Dead Production
28 1 7.5
27 0 5.2
27 0 11.5
27 0 10.9
24 3 11.5
26.6 0.8 9.8
4
14.3
this condition is unknown. This physiological disturbance perhaps had a considerable effect on the mortality in this pen. The best viability, when all things were considered, was in the oat-fed lot (pen 9B). These birds were healthy and in excellent flesh at the completion of the experiment. This was the only group which seemed to show considerable deviation in mortality from that of the control pen. There is an indication from this study that oats in the ration might increase the viability of the breeders. Egg Production The average egg production was highest in the control pen fed mixed grains, yielding an average of 15.2 eggs per hen per month. The corn-fed birds with 14.1 eggs per hen was the only group which approached the production of pen 2. The production of the oat-fed group was considerably below that in pens 1 and 2. The production of the wheat-fed group was consistently low and was less than half that of the control pen, and about half that of the corn-fed group. The emaciated condition of the birds in this pen, due to diarrhea, was probably a causative factor in this low production.
Effects on Hatching Eggs Fertility In the first series, pen 1 was the only lot which gave even fair fertility (85.4 percent) of the eggs set. Pens 2 and 9B were somewhat lower with 59.2 and 47.7 percent, respectively (see Table 4). Pen 9A was extremely low (19.2 percent), and was the lowest fertility obtained with the eggs from any pen throughout the entire experiment. This might be explained by recalling that these birds were in a condition of excessive diarrhea and this physiological disturbance was inhibitory to proper mating. It will be remembered that the eggs used in this series were collected after the breeders had been fed the experimental feed for only two weeks and apparently the wheatfed birds had not at that time been able to adjust themselves to their new feed. The fertility in series 2 was considerably higher than in the previous one and if the pooled average is considered it was the best of the four series, pen 9A was the highest (95.0 percent) while pens 9B, 2, and 1 followed in descending order; however, all four pens gave good fertility of over 90 percent. In series 3 the fertility of all the pens was in the same order as the preceding
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1
EFFECT OF SINGLE CEREAL GRAINS UPON HATCHABILITY AND GROWTH
uation and placing the control pen at 100, the following table has been developed: TABLE 5.—Comparative value of grains fed to breeders in relationship to fertility of eggs produced Feed
Pen No.
Mixed Grain = 100 108 100 86 99
Corn Mixed grains Wheat Oats
1 2 9A 9B
Embryo Mortality
TABLE 4.—Percent fertility of eggs set Pens Series Pen 1
Pen 2
Pen9A
Pen 9B
I II III IV
85.4 91.0 73.5 88.0
59.2 92.9 80.4 100.0
19.2 95.0 91.7 89.5
47.7 93.4 89.5 79.0
Mean of Total
84.5
78.3
67.5
77.6
Percent hatckability of fertile eggs I II III IV
85.5 60.7 50.0 63.6
62.2 58.2 61.4 64.0
100.0 94.7 63.6 100.0
86.9 77.1 73.5 83.6
Mean of Total
69.2
63.3
90.4
79.8
When the mean of the total eggs set was considered the data presented in this study indicated that corn was superior to mixed grains for fertility. It appeared that wheat was superior to corn after the physiological adjustments had been made to the diet. By using Crampton's (1936) method of eval-
The relative time at which the embryos died should be considered in a study of hatchability. The dead embryos in series 1 were all examined and when they were found to be rather uniformly distributed throughout the period, it was considered adequate to concentrate them into groups of 7, 18, and 21 days as they appeared dead at the different times of candling. From the data in Table 6, it is apparent that wheat is superior to the other single cereals or to a ration of mixed grains for the production of viable embryos. Statistical Analysis of the Hatchability of the Eggs A statistical analysis showed there was a highly significant difference between the pens in series 1, 2, and 4, and a significant difference between the pens in series 3. It was also quite evident that the difference in the pooled data from the four series was highly significant. It is interesting to
TABLE 6.—Comparison of embryo mortality at different stages of development for the various pens
Pen No. 1 2 9A 9B
Embryo Mortality
Total Fertile Eggs 185 241 52 163
7 days
Total
21 days
18 days
No.
%
No.
%
No.
%
No.
%
20 22 2 7
10.8 9.1 5.8 4.2
13 27 0 5
7.0 11.2 0.0 3.0
24 42 2 21
13.0 17.8 3.8 12.9
57 91 5 33
30.8 37.7 9.6 20.2
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series. The reduction in pens 9A and 9B was not quite so acute as that in pens 1 and 2. After the third series the hens were taken off the experimental feeds and were fed mixed grains for four weeks prior to collecting eggs for series 4. The order of fertility (see Table 4) was somewhat changed in this series; pen 2 led with 100 percent, followed in descending order by pens 9A, 1, 3, and 9B.
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VELAN D. CALL AND H. L. WILCKE
to consider the possibilities that such may be the case. More extensive study and larger numbers of eggs are necessary to verify this assumption. Pen 9B differed significantly from pen 2. The figures as presented in Table 5 show that oats, as far as this study indicated, was superior to mixed grains and corn for the production of good hatching eggs. When the mean of the total fertile eggs hatched was considered the data presented in this study indicated that wheat was superior to the other single grains and also to mixed grain. These data did not agree in all detail with the results reviewed by Crampton (1936), but generally speaking they were quite comparable. This study was made using only one single cereal, while the studies reported by Crampton (1936) used the only grain as the chief source of grain fed. By placing the control pen (mixed grains) at 100, the following table has been developed: TABLE 7,-—Comparative value of grains fed to breeders in relationship to hatchability of eggs produced, with mixed grains placed at 100 Pen 1 2 9A 9B
Feed
Mixed Grains = 100
Corn Mixed grains Wheat Oats
111 100 152 125
Growth of Chicks The chicks hatched from the eggs of all the series had a rather uniform incubation weight. It was noted, however, that chicks from pens 9A and 9B appeared more vigorous than those of the other pens. In series 1 there was a significant difference between mean weights of chicks from the pens at four weeks of age due to the high weight attained by the wheat birds and the low weight of the corn birds. The small number of chicks were due to an outbreak of chick bronchitis in the
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note that these results were quite consistent throughout the entire four series. These series were analyzed to determine what pens were responsible for the differences between pens within a series. Chisquare was used for determining the comparison between pens within each series. It was not found necessary to make this comparison for all pens because some were so close it was obvious there was no difference. The hatchability of eggs from pen 2 was highly significantly different from the other three pens. No other differences between pens were significant. Although there was a difference of about 14.5 percent between pens 9A and 1, the difference was not significant because of the small number of eggs in pen 9A. All the pens with the exception of 9B showed a highly significant difference from 9A in the second series. The results of this hatch might be separated into two groups—9A and 9B, and 1 and 2—each group showing considerable difference from the other group, but between the two pens within each group there was a non-significant variation in relation to hatchability. In other words wheat and oats were comparable, as were corn and mixed grain. When the pooled data of the four series were used, the Chi-square value was highly significant. Although there was a difference of over 10 percent of the averages of pens 9A and 9B it was not statistically significant, but the former was highly significantly different from the other two pens. The above evidence indicates that wheat is superior to mixed grains or corn for good hatchability. This agrees quite favorably with the evidence produced by Smith (1935) and Crampton (1936). Regardless of the fact that there is no statistical evidence for believing that wheat is superior to oats for hatchability of eggs, the fact that wheat is consistently higher leads one
EFFECT OF SINGLE CEREAL GRAINS UPON HATCHABILITY AND GROWTH
weeks of age the only significant difference was between the sexes. The total mean weights of both males and females were considerably below that found in the other two series at the same age. About the time the feed for this series was mixed a shipment of poor cod liver oil was received and used in the ration. It was not discovered until later when certain lots of chicks at the station started to develop rickets. As soon as this difficulty was discovered and remedied growth proceeded normally. At the 10-week stage, as was expected, there was a highly significant difference in the weights of the males and females. This was not due to the feed but is normal of birds of this age regardless of the type of rations. There was also a significant
TABLE 8.—Weight of chicks 4 weeks
I
II
III
Females
Males
Series Pen
No.
Mean Weight Grams
No.
Mean Weight Grams
1 2 9A 9B
20 12 1 7
199.0 255.8 270.0 217.1
22 12 6 6
191.4 216.7 230.0 198.3
Total
40
212.0
42
201.4
1 2 9A 9B
12 20 4 20
168.3 159.0 182.5 167.0
18 24 12 17
158.6 151.9 162.1 155.4
Total
56
165.5
71
156.1 ,
1 2 9A 9B
6 17 3 11
198.0 204.5 216.0 239.6
7 15 4 10
185.0 193.6 218.0 215.1
Total
37
214.8
36
200.5
1 2 9A 9B
12 16 3 18
744.2 717.4 743.3 739.4
17 22 12 16
596.5 599.1 597.5 600.6
Total
49
733.6
67
595.5
'
10 Weeks IV
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brooder room where these birds were kept. They were held for a week after the infection was severe in other brooders in the same room. Quite a number of these birds died just a few days prior to the time they were four weeks of age. It is noted, however, that the growth rate for series 1 is the same as for series 3 and superior to series 2, indicating that the weight was not affected by the disease. Chicks from the mixed grains and oat pens were intermediate. Two analyses of weights were made of the chicks hatched in series 2, one at four weeks and the other at 10 weeks of age. The second study was made to determine whether the feed of the parent stock had any influence upon the weight of the progeny for a longer period of time. At four
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VELAN D. CALL AND H. L. WILCKE
SUMMARY Four lots of yearling hens were used in this experiment, and were at the beginning a rather uniform group. They were all kept under as nearly similar conditions of housing and management as possible. The variations of feed, as far as it was possible to estimate, occurred only in the grains fed. All were supplemented with similar sources of vitamins, proteins, and minerals. All eggs were handled and incubated under the same conditions. The chicks hatched were treated in a uniform manner. Mortality was high in all lots of breeders, but oats seemed to improve viability. Wheat fed as the only grain produced a diarrhea in adult birds and apparently was a contributing factor in high mortality. Egg production was markedly reduced in the wheat and oat pens. The production in the other pens was rather uniform, with corn being equal to mixed grains for e[g production. Fertility was not affected significantly by the different rations.
i
Hatchability was best with eggs from the wheat birds, followed by oats, with corn and mixed grains approximately equal. Hens fed wheat or oats rations produced chicks with more vigor than those from hens fed corn. Chicks hatched from eggs of the various pens showed some variation in weight at four weeks of age, but-net--at-~hatehing_. time or at 10 weeks.'It seems questionable ' if grains in the diet of the parental stock I have much effect upon the subsequent .; growth of chicks. ..„..—-""" LITERATURE CITED
Bearse, G. E. and M. W. Miller, 1937. The effect of varying levels of vitamin A in the hen ration on the vitamin A content of the egg yolk, on hatchability and on chick livability. Poul. Sci. 16:39-43. Canada, Dept. of Agr., 1924. Ont. Exp. Sta. Report of Supt. (S. Ballantine), pp. S2-S8. Carver, J. S., E. I. Robertson, D. Brazie, R. H. Johnson, and J. L. St. John, 1934. The vitamin D requirements of chickens. Wash. Agr. Exp. Sta. Bui. 299. Crampton, Earle W., 1936. The comparative feeding values for poultry of barley, oats, wheat, rye, and corn. Dominion of Canada National Research Council Rpt. 29. Halpin, J. G. and J. B. Hayes, 1934. Feeding for eggs. Wis. Univ., Col. of Agr., Ext. Cir. 141, 5th edition. Heiman, Victor, J. S. Carver, and J. L. St. John, 1936. The protein requirements of laying hens. Wash. Agr. Exp. Sta. Bui. 331. Landauer, Walter, 1937. The hatchability of chicken eggs as influenced by environment and heredity. Storrs Agr. Exp. Sta., Conn. State College. Bui. 216. Morgan, C. L., 1930. Poultry feeding experiments. III. Ground barley vs. ground yellow corn in the mash for layers and breeders. S. Car. Agr. Exp. Sta. Bui. 273. Murphy, R. R., J. E. Hunter, and H. S. Knandel, 1936. The vitamin D requirements of growing chicks and laying hens. Pa. Agr. Exp. Sta. Bui. 334. Nestler, R. B., R. C. Byerly, N. R. Ellis, and R. W. Titus. 1936. A new factor, not vitamin G, necessary for hatchability. Poul. Sci. IS :6770.
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variation between mean weights of pens at this age due to the chicks hatched from pen 9A, whereas the mean weights for both male and female chicks from the other pens were very uniform. In series 3 there were no significant variations between either sex or pens, indicating that this group was rather homogenous in weight at four weeks of age. It is of interest to note that the mean weights of both the males and females were the same in series 1 and 3. There was considerably less variation between the weights of the different lots in the females than in the males. Since the data are not consistent from series to series, it must be assumed from the data collected that grains fed to the breeding stock have no effect upon the subsequent growth of the chicks.
EFFECT OF SINGLE CEREAL GRAINS UPON HATCHABILITY AND GROWTH
the poultry ration. Okla. Agr. Exp. Sta. Bui. 166. Sherwood, R. M., and G. S. Fraps, 1936. The vitamin A requirements of hens for egg production. Texas Agr. Exp. Sta. Bui. 514. Smith, J. B., 1935. The cereal grains and their use in poultry nutrition. 1. Hatchability Studies. Sci. Agr. 16:73.
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Norris, L. C , H. S. Wilgus, A. T. Ringrose, Victor Heiman, and G. F. Heuser, 1936. The vitamin G requirement of poultry. New York (Cornell) Agr. Exp. Sta. Bui. 660. Payne, Loyal F., 1934. The comparative nutritional value of sorghum grains, corn, and wheat as poultry feeds. Kans. Agr. Exp. Sta. Bui. 268. Penquite, R., R. B. Thompson, and H. R. Naylor, 1927. The value of certain scratch grains in
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