High Levels of Alfalfa Meal in Diets for Chickens B U R T W.
HEYWANG
Bureau of Animal Industry, Agricultural Research Administration, U. S. Department of Agriculture, Glendale, Arizona (Received for publication April 3, 1950)
H E results of experiments previous to those of Alder (1946) indicated that mashes fed to poultry should contain only rather small quantities of alfalfa meal. The common opinion was t h a t its fiber content prevented the advantageous inclusion of more t h a n 5 to 1\ percent in mashes for either growing or laying chickens. However, the data of Alder (1946) showed that mashes for turkeys fed a mash-grain diet could contain as much as 30 or 35 percent alfalfa meal without adversely affecting their weight or feed consumption per pound of gain by the time they were 29 weeks old. These data apparently stimulated new investigations at several experiment stations to determine the maximum level at which alfalfa meal can be included safely in mashes for chickens.
feed intake, and t h a t the fiber in alfalfa meal is not the offending substance. T h e chickens were four weeks old at the end of the experiments. Another report on experiments at the University of California (Peterson, 1950) states t h a t saponins in alfalfa meal are probably responsible for its depressing effect on the growth of young chickens, and t h a t cholesterol offsets the effect. The first of a series of experiments on the effect of the dietary level of alfalfa meals on growing and laying chickens was started at the Southwest Poultry Experiment Station, Glendale, Arizona in 1946. Some of the d a t a obtained in one of the experiments with growing chickens and in three of the experiments with laying chickens are given and discussed in this paper.
Cooney and associates (1948) reported the results of an experiment in which dehydrated alfalfa meal at 0, 5, 10, 15, 20, and 25 percent levels was included in the diets of New Hampshire chickens until they were eight weeks old. Each addition of 5 percent dehydrated meal to the diet above the 5 percent level had an increasingly depressing effect on the growth and feed consumption of the chickens. Lepkovsky and co-workers (1950) reported t h a t dehydrated alfalfa meal contains a substance t h a t depresses the growth of young chickens, t h a t the growth depression is associated with a decrease in 804
PROCEDURE AND RESULTS
Growing
Chickens
Fifty day-old White Leghorn pullets were in each of the 11 groups at the start of the experiment with growing chickens. They were brooded under electric hovers in similar houses, and were weighed individually on the first and fourteenth days after hatching and at intervals of 14 days thereafter. Feed consumption records were kept for the same periods. Statistical analysis of the weight d a t a was made in accordance with the method suggested by Titus and H a m m o n d (1935). The composition of the 11 diets, each of which was fed to a different group, is
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T
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ALFALFA MEAL IN CHICK DIETS
given in Table 1. The soybean meal and limestone contents of the diets were varied so that each diet contained about 18.5 percent protein, 1.2 percent Ca, and 0.8 percent P. Adjustments were made in the ground red milo content of the diets to compensate for their varying contents of
weights and feed consumption of the pullets in the different groups when they were 4, 8, 12, 16, and 20 weeks old. The depressing effect on the growth of the pullets receiving dehydrated alfalfa meal was evident at the 25 percent level when they were four weeks old, but it was not
TABLE 1.—Composition of diets fed in experiment with growing chickens Diet
Ground red milo 53.0 Dehydrated alfalfa meal — Sun-cured alfalfa meal Ground wheat 10.0 Wheat bran 10.0 Meat scraps 8.0 Soybean meal 7.0 Cottonseed meal 5.0 Dried whey 5.0 Ground limestone 1.0 1 Manganized salt 0.5 Vitamin A and D feeding oil (2,000 A, 400 D) 0.5 1
2
3
4
5
6
7
8
9
10
11
34.0 25.0
37.8 20.0
41.6 15.0
45.4 10.0
49.2 5.0
32.9
36.7
41.0
45.0
49.0
10.0 10.0 8.0 2.0 5.0 5.0 0.5
10.0 10.0 8.0 3.0 5.0 5.0 0.2 0.5
10.0 10.0 8.0 4.0 5.0 5.0 0.4 0.5
10.0 10.0 8.0 5.0 5.0 5.0 0.6 0.5
10.0 10.0 8.0 6.0 5.0 5.0 0.8 0.5
25.0 10.0 10.0 8.0 3.0 5.0 5.0 0.1 0.5
20.0 10.0 10.0 8.0 4.0 5.0 5.0 0.3 0.5
15.0 10.0 10.0 8.0 4.5 5.0 5.0 0.5 0.5
10.0 10.0 10.0 8.0 5.4 5.0 5.0 0.6 0.5
5.0 10.C 10.C 8.0 6.2 5.0 5.C 0.8 0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
—
A mixture of 100 pounds table salt and 4.5 pounds manganous sulphate tetrahydrate. TABLE 2.—Average weights and diet consumption in experiment with growing chickens Cumulative average diet consul consuroption in grams a t
Average weight in grams att
Alfalfa meal in diet
4 wks. 8 wks. 12 wks. 16 wks. 20 wks. 4 wks. 8 wks. 12 wks. 16 wks. 20 wks. 0
217
553
973
1,334
1,652
454
1,601
3,390
5,733
8,257
5% 10% 15% 20% 25%
dehydrated dehydrated dehydrated dehydrated dehydrated
224 218 218 211 194
570 560 573 544 512
993 981 985 947 914
1,336 1,298 1,333 1,284 1,215
1,631 1,572 1,552 1,552 1,469
477 463 468 468 448
1,700 1,701 1,748 1,744 1,670
3,688 3,735 3,739 3,810 3,638
6,010 6,060 6,129 6,320 6,086
8,660 8,670 8,844 9,100 8,776
5% 10% 15% 20% 25%
sun-cured sun-cured sun-cured sun-cured sun-cured
214 204 183 175 156
564 542 507 471 401
995 966 909 820 705
1,316 1,296 1,253 1,146 967
1,629 1,547 1,457 1,341 1,187
471 452 417 349 363
1,722 1,659 1,639 1,548 1,403
1,703 3,615 3,640 3,364 3,072
6,065 6,016 6,146 5,736 5,244
8,729 8,683 8,678 8,256 7,681
alfalfa meal, soybean meal, and limestone. The dehydrated alfalfa meal was produced in Arizona and contained about 18 percent protein. The sun-cured alfalfa meal was produced in Colorado and contained about 15.5 percent protein. Shown in Table 2 are the average
%
evident at the other levels until they were 16 weeks old. At 12 weeks, differences between the average weights of the pullets receiving the basal diet and those receiving 5, 10, 15, or 20 percent dehydrated meal are not statistically significant. Of statistical significance when the
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806
BURT W. HEYWANG
drated meal was greater than that of the pullets fed the basal diet, although in some instances the average weight of the pullets was considerably less. Growth depression was associated with a lessened consumption of the diets containing sun-cured alfalfa meal only when the pullets were fed 25 percent of the meal. The next poorest growth and lowest diet consumption occurred when 20 percent of this meal was fed. Although those pullets, when 12, 16, and 20 weeks old, weighed consideraly less than the pullets receiving the basal diet, they, had consumed about the same average quantity of diet. Data on the efficiency of feed utilization are not considered of sufficient pertinence to warrant their inclusion in Table 2. In most instances, at the end of 4, 8, 12, 16, and 20 weeks of the experiment the efficiency of feed utilization of the pullets fed the basal diet was greater than that of the pullets fed any of the other diets. In general, the efficiency of feed utilization decreased as the level of either kind of alfalfa meal in the diet increased. Laying Chickens In all three experiments with laying chickens, the different groups were confined in similar pens in the same house. They were weighed individually on the first and last days of the experiments, but diet consumption records were kept at successive 28-day intervals. They were trapnested. In experiments 2 and 3 two males were placed with each group before eggs were saved for incubation and then moved to a different group each week. All sound eggs were saved for incubation during seven-day periods and put in the incubator on the eighth day. The eggs were gathered several times daily and stored at a temperature of 50 degrees F. prior to incubation.
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pullets were 16 weeks old are the differences between the average weight of those fed the basal diet (diet 1) and of those fed 10, 20, or 25 percent dehydrated meal. When the pullets were 20 weeks old, the difference between the average weight of the pullets fed the basal diet and of those fed 15 percent dehydrated meal is also significant. In this experiment the growth depressing effect of the sun-cured meal was greater than that of the dehydrated meal at the 15, 20, and 25 percent levels. At four weeks of age, significant differences were found between the average weight of the pullets fed the basal diet and of those fed 15, 20, or 25 percent sun-cured meal. When they were 16 weeks old, the difference is also significant when 10 percent sun-cured meal was fed. These weight data were obtained on only one lot of sun-cured alfalfa meal and one lot of dehydrated alfalfa meal, and they should not be interpreted to mean that the growth depressing effect of all sun-cured alfalaf meals is greater than that of all dehydrated alfalfa meals. It seems probable that the variation in growth depressing effect might be as great among different lots of sun-cured meals or among different lots of dehydrated meals as it was between single lots of the two kinds of meals in this experiment. These weight data do show, however, that alfalfa meals may vary considerably in their growth depressing effect. In Table 2, comparisons of the data on the diet consumption and weight of the pullets fed the basal diet with those of the pullets fed 20 or 25 percent dehydrated meal show that growth depression was not associated with lessened consumption of the diets containing the dehydrated meal even when the pullets were only 4 weeks old. By the time they were 8, 12, 16, or 20 weeks old, the diet consumption of the pullets fed any of the five levels of dehy-
ALFALFA MEAL IN CHICK DIETS
alfalfa meal above the 5 percent level, or the sun-cured alfalfa meal above the 10 percent level, resulted in appreciable decreases in egg production. Comparisons of the data from the pullets fed the basal diet (diet 12) with those from the pullets fed the other diets show that these decreases in egg production were not accompanied by, or associated with, decreases in diet consumption. The slightly lower consumption of the diets containing 25 percent of dehydrated or sun-cured meal is attributable to the lower weight of the pullets fed those diets. At the end of the experiment, the pullets fed 20 or 25 percent dehydrated or sun-cured meal still weighed less than the pullets fed the other diets. The greatest percentage gain in weight was made by the pullets that weighed the least when they were 20 weeks old (those fed 20 or 25 percent sun-cured meal), but it seems doubtful if either they or the pullets fed 20 or 25 percent dehydrated meal would ever have weighed as much as those fed the basal diet. However, these data do not show clearly that the meals at the 20 and 25 percent levels had an adverse effect on the weight of the laying pullets. Their relatively low weights when they were 48 weeks old may have been due to the retardation of their weights before they started to lay. At the start of experiment 2 with laying chickens, 25 White Leghorn pullets were in each of the nine groups. The average egg production and the average weight of the pullets in the different groups were about the same when the experiment was started. They had been fed growingchicken diets containing 10 percent dehydrated alfalfa meal from the time they were hatched. The dehydrated alfalfa meal was produced in Arizona and contained about 19 percent protein. When it was included in their diets at the 30 and 35 percent levels,
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Hendricks' (1935) method for the estimation of the statistic f and the calculation of the variance among its values was used in the analysis of the hatchability data. For each of the 11 groups in experiment 1 with laying chickens, 30 White Leghorn pullets were selected from each of the 11 groups in the experiment with growing chickens. The selection was based mainly on weight, and the average weight of the 30 pullets in each group was approximately the same as the average weight of all the pullets in the group from which they were selected. These pullets continued to receive the same level of the same kind of alfalfa meal in their diet thet they had received since they were hatched. The alfalfa meals were from the same lots as those used in the experiment with growing chickens. The composition of the diets was changed slightly to make them suitable for laying chickens: cottonseed meal was omitted to lower their protein content, bone meal was included, and their content of ground limestone was increased. In this and the two other experiments with laying chickens, the quantities of soybean meal, ground limestone, and bone meal in the diets were varied so that each diet contained about 17 percent protein, 2.4 percent Ca and 1.0 percent P. Adjustments were made in the ground red milo maize content of the diets to compensate for their varying contents of alfalfa meal, soybean meal, bone meal, and limestone. The composition of the diets is shown in Tables 2, 3, 4, and 5. Shown in Table 6 are the data obtained in experiment 1 on the average total egg production, the average total diet consumption, and the average weight of the pullets in the different groups during the period of 28 weeks after they were 20 weeks old. It is apparent that the inclusion in their diet of either the dehydrated
807
808
BURT W. HEYWANG TABLE 3.— Composition of diets fed in experiment 1 with laying chickens Diet 12
14
15
16
17
18
19
20
21
22
36.0 25.0
39.8 20.0
43.6 15.0
47.4 10.0
51.2 5.0
34.9
38.7
43.0
47.0
51.0
10.0 10.0 8.0 2.0 5.0 2.0 1.0 0.5
10.0 10.0 8.0 3.0 5.0 2.2 1.0 0.5
10.0 10.0 8.0 4.0 5.0 2.4 1.0 0.5
10.0 10.0 8.0 5.0 5.0 2.6 1.0 0.5
10.0 10.0 8.0 6.0 5.0 2.8 1.0 0.5
25.0 10.0 10.0 8.0 3.0 5.0 2.1 1.0 0.5
20.0 10.0 10.0 8.0 4.0 5.0 2.3 1.0 0.5
15.0 10.0 10.0 8.0 4.5 5.0 2.5 1.0 0.5
10.0 10.0 10.0 8.0 5.4 5.0 2.6 1.0 0.5
5.0 10.0 10.0 8.0 6.2 5.0 2.8 1.0 0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
A mixture of 100 pounds table salt and 4.5 pounds manganous sulphate
tetrahydrate.
TABLE 4.—Composition of diets fed in experiment 2 with laying chickens Diet
Ground red milo Dehydrated alfalfa meal Ground wheat Wheat bran Meat scraps Sardine meal Soybean meal Ground limestone Steamed bone meal Manganized salt 1 Butyl fermentation solubles (500 units riboflavin per gm.) Vitamin A and D feeding oil (2,000 A, 400 D) 1
23
24
25
26
27
28
29
30
31
57.8 10.0 10.0 10.0
37.7 25.0 10.0 10.0 10.0
43.5 20.0 10.0 10.0 10.0
47.3 15.0 10.0 10.0 10.0
51.0 10.0 10.0 10.0 10.0
40.0 25.0 10.0 10.0
43.8 20.0 10.0 10.0
47.7 15.0 10.0 10.0
51.5 10.0 10.0 10.0
—
—
—
1.0 1.5 3.3 0.5
2.0 1.8 1.2 0.5
3.0 2.0 1.2 0.5
4.0 2.4 1.1 0.5
7.5 1.0 1.7 3.3 0.5
—
7.0 2.7 1.0 0.5 0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
—
•
7.5 2.0 2.0 3.2 0.5
7.5 3.0 2.2 3.1 0.5
7.5 4.0 2.4 3.1 0.5
A mixture of 100 pounds table salt and 4.5 pounds manganous sulphate tetrahydrate. TABLE 5.—Composition of diets fed in experiment 3 with laying chickens Diet
Ground red milo Sun-cured alfalfa meal Dried alfalfa stems Ground wheat Wheat bran Sardine meal Soybean meal Ground limestone Steamed bone meal Manganized salt 1 Butyl fermentation solubles (500 units riboflavin per gm.) Vitamin A and D feeding oil (2,000 A, 400 D) 1
32
33
34
35
36
58.2
38.0 25.0
39.5
41.8 20.0
44.0
— —
—
—
10.0 10.0 7.5 7.0 2.8 3.0 0.5
10.0 10.0 7.5 3.0 1.5 3.5 0.5
—
16.0 10.0 10.0 7.5 10.0 2.2 3.3 0.5
10.0 10.0 7.5 4.0 1.8 3.4 0.5
—
12.5 10.0 10.0 7.5 9.0 2.2 3.3 0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
A mixture of 100 pounds table salt and 4.5 pounds manganous sulphate tetrahydrate.
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55.0 Ground red milo Dehydrated alfalfa meal — Sun-cured alfalfa meal 10.0 Ground wheat 10.0 Wheat bran 8.0 Meat scraps 7.0 Soybean meal 5.0 Dried whey 3.0 Ground limestone 1.0 Steamed bone meal 0.5 Manganized salt 1 Vitamin A and D feeding oil (2,000 A, 0.5 400 D)
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809
ALFALFA M E A L IN CHICK DIETS
TABLE 6.—Experiment 1 with laying chickens—egg production, diet consumption, and live weight Alfalfa meal in diet
Average total Average total numbers of eggs diet consumption per bird per bird
0
Average weight at 20 wks. 48 wks.
Average gain in weight Percent
Kilograms
Grams
Grams
83
13.3
1,652
1,749
6
dehydrated dehydrated dehydrated dehydrated dehydrated
78 56 56 69 59
13.9 13.8 14.1 15.1 13.0
1,631 1,572 1,552 1,552 1,469
1,733 1,770 1,744 1,599 1,526
6 13 12 3 4
5% 10% 15% 20% 25%
sun-cured sun-cured sun-cured sun-cured sun-cured
76 84 57 64 42
13.2 14.5 13.8 14.4 12.9
1,629 1,547 1,457 1,341 1,187
1,697 1,736 1,686 1,583 1,553
4 12 16 18 31
this dehydrated meal had retarded the growth of young chickens by the time they were two weeks old. Data on the egg production, diet consumption, and weight of the pullets and on the hatchability of their eggs, during the 28 weeks of experiment 2, are given in Table 7. The average total egg production was less on all eight diets containing dehydrated meal than it was on the diet containing none, and it decreased as the dehydrated meal level increased whether the diets contained sardine meal or meat scraps. However, at the same level of dehydrated meal, egg production was slightly higher on the diets containing sardine meal than on these containing meat scraps.
Average total diet consumption was about the same in all nine groups. It is thus apparent that the decreases in egg production were not associated with decreases in diet consumption. On none of the eight diets containing dehydrated meal was average hatchability (the average of the individual hatchability ratios) lower than it was on the basal diet (diet 23). In each instance, average hatchability on 15, 20, or 25 percent -dehydrated meal was higher when the diets contained sardine meal than when they contained meat scraps. The loss in average weight of the pullets in all nine groups is attributable to the fact that the latter part of the experi-
TABLE 7.—Experiment 2 with laying chickens—egg production, diet consumption, live weight, and hatchability in diet (Diets with meat scraps) 0 10% dehydrated 15% dehydrated 20% dehydrated 25% dehydrated (Diets with sardine meal) 10% dehydrated 15% dehydrated 20% dehydrated 25% dehydrated 1
Average total Average total Average weight number of diet consumpat eggs per bird tion per bird Start End
Average loss m weight
eggs set
Average hatchability 1
117 105 95 93 86
Kilograms 21.2 21.5 21.1 21,4 21.0
Grams 1,698 1,701 1,712 1,698 1,722
Grams 1,433 1,413 1,319 1,348 1,273
Percent 16 17 23 21 26
Number 499 490 381 365 309
Percent 86.8 92.5 88.3 87.7 87.2
109 103 97 91
20.9 21.3 21.0 21.2
1,709 1,690 1,703 1,699
1,425 1,445 1,374 1,372
17 14 19 19
551 537 427 495
92.3 94.0 93.1 95.0
Average of individual hatchability ratios.
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5% 10% 15% 20% 25%
810
BURT W. HEYWANG
The sun-cured meal was produced in Arizona and contained about 17 percent protein and 27 percent fiber. When it was fed at 20 and 25 percent levels, this meal had retarded the growth of young chickens by the time they were two weeks old. The alfalfa stems were also produced in Arizona and- contained about 6 percent protein and 43 percent fiber. Data on the egg production, diet consumption, and weight of the pullets, and on the hatchability of their eggs during the 150 days of experiment 3 are given
TABLE 8.—Experiment 3 with laying chickens—egg production, diet consumption, live weight and hatchability Alfalfa meal in diet
Average loss in . weight
Fertile eggs set
Average hatchability 1
Percent 6
Number 523
Percent 90.4
75
Kilograms 14.5
20% sun-cured 25% sun-cured
64 45
15.0 13.4
2,087 2,075
1,823 1,674
13 19
463 335
86.7 85.0
0-12.5% stems 0-16 % stems
70 64
16.1 16.1
2,051 2,072
1,876 1,728
9 17
408 494
89.8 87.9
0
1
Average total Average total Average weight number of diet consumpat End eggs per bird tion per bird Start Grams Grams 2,072 1,942
Average of individual hatchability ratios.
scraps. In view of the results reported by Peterson (1950), one possible explanation is that the sardine meal contained more cholesterol than did the meat scraps. At the start of experiment 3 with laying chickens, 30 New Hampshire pullets were in each of the five groups. The average weight and the average egg production of the pullets in the different groups were about the same when the experiment was started. They had been fed growing-chicken diets containing 10 percent dehydrated alfalfa meal from the time they were hatched. All the all-mash diets fed in experiment 3 contained sardine meal. The alfalfa stems included in two of the diets furnished the same quantity of fiber to those diets as would have been furnished by 20 and 25 percent, respectively, of the suncured meal.
in Table 8. The adverse effect of the suncured meal on egg production and weight in this experiment was even more severe than that of the dehydrated, meal in experiment 2. As in experiment 2, the loss in average weight of the pullets in all the groups is attributable to the hot weather during the latter part of the experiment. A decrease in egg production was associated with a decrease in the consumption of only one diet—the one containing 25 percent sun-cured meal. In this experiment, the highest hatchability was obtained from the eggs of the pullets fed the basal diet (diet 32). However, the differences among the five groups are not statistically significant. The results of Lepkovsky and coworkers (1950) show clearly that the retarding effect of high levels of alfalfa
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ment was conducted during hot weather. In three of the four possible comparisons of pullets fed the same level of dehydrated meal, loss in weight was greater when the diet contained meat scraps than when it contained sardine meal. Pullets fed meat scraps and 25, 20, or 15 percent dehydrated meal had the greatest loss in weight. There may be several explanations for the better results in this experiment when otherwise similar diets contained sardine meal than when they contained meat
ALFALFA MEAL IN CHICK DIETS
meals on the growth of young chickens is not due to the fiber content of the meals. It seems probable, therefore, that the adverse effect of the alfalfa stems on egg production and weight of the two groups of pullets in this experiment was due to some factor, possibly saponins, other than fiber in the stems. SUMMARY
tained sardine meal instead of meat scraps. Average total egg production decreased as the level of dehydrated meal increased, but the average total diet consumption was about the same in all groups. On none of the eight diets containing dehydrated meal was average hatchability lower than when no dehydrated meal was fed. At the three highest levels of dehydrated meal, egg production and hatchability were greater when the diet contained sardine meal than when it contained meat scraps. The poorest maintenance of weight was by the pullets fed the diets with meat scraps and more than 10 percent of sun-cured meal. All five diets in the experiment with laying New Hampshire pullets contained sardine meal. Sun-cured alfalfa meal at the 20 and 25 percent levels, and alfalfa stems at levels to supply as much fiber as 20 or 25 percent, respectively, of the sun-cured alfalfa meal, had an adverse effect on egg production and body weight that was not associated with decreased diet consumption. Differences in hatchability among the five groups were not statistically significant. Alfalfa meal as 5 percent of the diet, the level commonly used, did not significantly depress growth or egg production in any case. REFERENCES * Alder, B., 1946. Economical turkey production in Utah. Utah Agr. Exp. Station Mimeograph Series No. 323. Cooney, W. T., J. S. Butts and L. E. Bacon, 1948. Alfalfa meal in chick rations. Poultry Sci. 27: 828-830. Hendricks, W. A., 1935. The statistical treatment of hatchability data. Poultry Sci. 14: 365-372. Lepkovsky, S., W. Shaeleff, D. Peterson and R. Perry, 1950. Alfalfa in chick rations. Poultry Sci. 29: 208-213. Peterson, D. W., 1950. Alfalfa in chick rations. California Agriculture 4: 13. Titus, H. W., and J. C. Hammond, 1935. A method of analyzing the data of chick nutrition experiments. Poultry Sci. 14: 164-173.
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Diets containing 0, 5, 10, 15, 20, or 25 percent dehydrated or sun-cured alfalfa meal were fed to different groups of White Leghorn pullets until they were 20 weeks old. The data show that alfalfa meals may vary considerably in their growth depressing effect. Growth depression was not accompanied by a decrease in diet consumptien at any level of the dehydrated meal. It was accompanied by a decrease in diet consumption throughout the entire experimental period at only the 25 percent level of the sun-cured meal. Some of the pullets continued to receive the same level of the same kind of alfalfa meal in their diet until they were 48 weeks old. The dehydrated meal above the 5 percent level, and the sun-cured meal above the 10 percent level, lowered egg production appreciably. The average total diet consumption during the last 28 weeks of the experiment was about the same in all groups. Data were also obtained in a second experiment with laying White Leghorn pullets, and in an experiment with laying New Hampshire pullets. All these pullets had been fed similar diets for growing chickens. One group in the second experiment with laying White Leghorns was fed an all-mash diet containing meat scraps but no alfalfa meal. The other groups were fed diets containing 10, 15, 20, or 25 percent dehydrated alfalfa meal; one diet with each level of dehydrated alfalfa meal contained meat scraps, and the other con-
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