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The Effect of Supplementary All-Mash Pellets in the All-Mash Feeding Program for Layers Using Automatic Feeders
SUPPLEMENTARY PELLETS FOR LAYERS
therapy, at levels favorable to egg production, was reinitiated. 8. Body weight changes, while the radioiodine-treated hens received no thyroxin, were similar to body weight changes that took place in the control hens at the same time, and appear to be related to seasonal changes in weight rather than to the level of circulating thyroxin.
Brody, S., 1945. Bioenergetics and Growth. The Reinhold Publishing Corporation, New York. Kleiber, M., 1947. Body size and metabolic rate. Physiol. Revs. 27: 511-541. Marine, D., 1922. The present status of the functions of the thyroid gland. Physiol. Revs. 2: 521551. Schultze, A. B., and C. W. Turner, 1945. The determination of the rate of thyroxine secretion by certain domestic animals. Missouri Agr. Exp. Sta. Res. Bui. 392. Winchester, C. F., 1940. Seasonal endocrine and metabolic rhythms in the domestic fowl. Missouri Agr. Exp. Sta. Res. Bui. 315. Winchester, C. F., C. L. Comar and G. K. Davis, 1949. Thyroid destruction by I131, and replacement therapy. Science, 110: 302-304. Winchester, C. F., and G. K. Davis, 1952. Influence of thyroxin on growth of chickens. Poultry Sci. 31:31-34.
The Effect of Supplementary All-Mash. Pellets in the AllMash Feeding Program for Layers Using Automatic Feeders CLARENCE E. L E E , OLIN A. ROWOTH, C. L. HENRY AND JOSEPH PRESTO Poultry Research Division, The Beacon Milling Company, Inc., Cayuga, N. Y. (Received for publication September 22, 1952)
T ) R I O R to the use of automatic feeders, •*• many reports had been published on different feeding systems for layers. Several workers (Morgan and Heywang, 1941; Morris, 1946; and Jensen and McGinnis, 1952) have shown that no significant increase in egg production was obtained when a pelleted all-mash laying ration was compared with an unpelleted all-mash laying ration. Previous work by Lee, Hamilton, Henry and Callanan (1939) showed that egg production was lower and feed cost per dozen eggs was higher when an all-mash ration supplemented with pellets was compared with a grain, mash and pellet feeding program. Following this work, Lee, Scholes and Henry (1944, 1949), using Leghorn,
Rhode Island Red and Rhode Island Red X Barred Plymouth Rock crossbred layers, found that a controlled feeding program of grain, mash and pellets gave better egg production than free choice feeding of grain and mash. Since the advent of the automatic feeders and with present government price support on grains, unpublished work by this division has shown that an all-mash laying ration, distributed by an electric motor driven automatic feeder, supplemented by a daily (hand fed) feeding of all-mash pellets gave comparable egg production and a slightly lower feed cost per dozen eggs when compared with a controlled feeding program of grain, mash and pellets. With the popularity of automatic
Downloaded from http://ps.oxfordjournals.org/ by Nathalia Oliveira on May 9, 2015
REFERENCES Biester, H. E., and L. H. Schwarte, 1952. Diseases of Poultry, 3rd Ed. The Iowa State College Press, Ames, Iowa. Blaxter, K. L., E. P. Reineke, E. W. Crampton and W. E. Petersen, 1949. The role of thyroidal materials and of synthetic goitrogens in animal production and an appraisal of their practical use. J. Animal Sci. 8: 307-352.
429
430
C. E. L E E , 0. A. ROWOTH, C. L. HENRY AND J. PRESTO
EXPERIMENTAL
The Single Comb White Leghorn pullets used in this investigation were obtained as day old chicks from a commercial hatchery. These birds were brooded and ranged together and fed a grain and mash feeding program. At the end of the growing period these pullets were carefully selected and randomly divided into two groups of 600 birds. Each of the two groups of pullets was placed in identical 30'X52' pens. The two pens were divided by a feed room and were located on the ground floor of a two-story cinder block laying house. Each pen was equipped in the same manner, including an automatic electric motor driven feeder with 37 linear ft. of feeding space per 100 birds, based on the number of birds at the beginning of the experiment. Both groups of birds were fed a 16% protein commercial all-mash laying ration (actual average analysis about 17%) ad libitum using identical automatic feeders which operated continuously for 13 hours
daily except for a two-hour period in late afternoon. During this two-hour period the birds in group #2 received a supplementary hand feeding of the 16% protein all-mash laying ration in pellet form. During the winter months each pen received a daily morning feeding of two pounds of grain mixture per pen in order to stimulate working in the litter. This investigation covered the pullet laying year of 365 days and a yearling laying period of 265 days. It was necessary to end the yearling laying period June 30th in order to make room for early hatched pullets. Artificial lights were used in both pens during the fall, winter and early spring to give a 13 hour day, except for a 47 day molting period during the yearling laying year from November 15, 1951 to January 1, 1952. There was no culling during this investigation except for one bird out of each pen at the end of the pullet laying year. A representative number of birds were weighed weekly up to the age of maturity and biweekly thereafter, except during the molting period, in order to obtain the average body weight of the birds in each group. Egg production, feed consumption and mortality were recorded and summarized monthly. RESULTS AND DISCUSSION
Table 1 presents a summary of the pullet year from October 10, 1950 through October 9, 1951 (365 days). The summary includes data on the average number of eggs per bird (hen-day basis), details of feed consumption and costs, cost of feed per dozen eggs and percent mortality. According to the Harper Adams standard (Dudley, 1932) there is a significant difference in the egg production during the pullet laying year in favor of the birds in
Downloaded from http://ps.oxfordjournals.org/ by Nathalia Oliveira on May 9, 2015
feeders increasing, there is a great demand by commercial poultrymen for a simplified feeding program for layers which will effectively utilize this labor-saving device without sacrificing maximum egg production. Since the grain, mash and pellet feeding program is not well adapted for use with present automatic feeders, it was concluded that further research should be conducted with all-mash feeding systems. Previous unpublished work by this division using all-mash rations (hand fed) showed the necessity of supplemental pellets in order to obtain maximum egg production; therefore, this investigation was conducted to see if maximum egg production could be obtained by eliminating the supplementary feeding of allmash pellets when the all-mash ration was fed by means of an automatic feeder.
SUPPLEMENTARY PELLETS FOR LAYERS TABLE 1.—Summary of data—pullet laying year
Number of birds Number eggs per bird Percent production Pounds mash per bird Pounds pellet per bird Pounds grain per bird Total feed consumed per bird (lbs.) Feed cost per bird—Total Feed per dozen eggs Cost of feed per dozen eggs Percent mortality
Group 1
Group 2
600 257.15 70.45 112.92 0.00 0.81
600 279.92 76.69 85.95 33.96 0.82
113.73 $5.80 5.31 $0,271 11.34
120.73 $6.19 5.18 $0,265 10.83
Group 2 receiving the daily supplementary feeding of all-mash pellets (hand fed). The birds in this group laid an average of 22.77 more eggs per bird than the birds in Group 1 receiving no pellets. The average feed consumption for the birds receiving pellets was 7 pounds greater per bird than the birds in Group 1; however, these birds (with pellets) showed a slightly better feed conversion. The feed cost per dozen eggs was 0.6 cent less for Group 2 despite the fact that these birds consumed more feed and the pellets were priced $1.50 (pelleting charge) TABLE 2.—Summary of data—yearling laying period (265 days only, including molt)
Number of birds Number eggs per bird Percent production Pounds mash per bird Pounds pellets per bird Pounds grain per bird Total feed consumed per bird (lbs.) Feed cost per bird—Total Feed per dozen eggs Cost of feed per dozen eggs Percent mortality
Group 1
Group 2
531 126.60 47.77 78.54 0.00 0.32
534 141.30 53.23 70.42 14.74 0.32
78.86 $3.92 7.47 $0,372 7.90
85.48 $4.25 7.26 $0,361 9.37
Stock used: S.C. White Leghorns. Hatched April 13, 1950. Time of experiment: October 10, 1951 through June 30, 1952 (265 days including a 47 day molting period Nov. 15, 1951 to Jan. 1, 1952).
higher per ton than the mash. Table 2 presents a summary of the yearling laying period from October 10, 1951 to June 30, 1952 (265 days including a 47 day molting period). As was the case in the pullet laying year the birds in Group 2 receiving the daily supplementary feeding of pellets (hand fed) ate more feed, and produced more eggs with a better feed conversion. These data show that the birds in Group 2 consumed an average of 6.62 pounds of additional feed per bird and laid an average of 14.70 eggs more per bird than the birds in Group 1. The feed cost per dozen eggs favored the birds in Group 2 by 1.1 cents per dozen eggs. It was unfortunate that this experiment had to be terminated before the completion of the yearling laying year since the birds in Group 2 were laying approximately 65% when the experiment had to be discontinued, while the birds receiving no pellets were beginning to molt and were laying only approximately 40%. During both laying years the mortality was not abnormal and was mainly due to leukosis. By comparing the weight of the same volume of the pellets and mash it was found that the density of the pellets was 1.214 greater than the mash. Using this figure to calculate the comparative feed consumption of the two groups on a volume basis, it was found that the average volume of feed consumed by each group was almost identical. The graph in Figure 1 shows the egg production by eggs per bird per month for the complete period of 630 days covering both laying years. This graph shows that the group receiving the supplementary pellets had a higher peak egg production and consistently laid more eggs during both laying years except during the molting period.
Downloaded from http://ps.oxfordjournals.org/ by Nathalia Oliveira on May 9, 2015
Stock used: S.C. White Leghorns. Hatched April 13, 1950. Time of Experiment: October 10, 1950 through October 9, 1951 (365 days).
431
432
C. E. L E E , 0. A. ROWOTH, C. L. HENRY AND J. PRESTO
iiso
nsi
Dec. Jan.
fcV. Haf.
fter.
rAay vta
nsi dorAVs
i1SO-H52L
FIG. 1. Egg production for 630 days.
5.5 +
5.0- •
f.5-> Group 1 Group t Oct.10-31 N-v. T>*«. J » * . F«V
Nar.
Ap
May
June
July
M<,-AV»
Au*
S« r +.
OcT.
N°».
1150 - m 2
FIG. 2. Average monthly body weight.
Dec. J a t .
F«W.
(No
Pellets)
(Witt, Pelt.ls) Ma«*. A p r . h a y
Ja
Downloaded from http://ps.oxfordjournals.org/ by Nathalia Oliveira on May 9, 2015
Osfc. 10-31 Nov. De«.. Jan. F«\>. /Aar. Af». M»» O w My fVj. S«rV. OcV. N.v.
433
GROWTH FACTOR IN ALFALFA
The graph in Figure 2 shows the average monthly body weight of the birds in the two groups, except during the molting period. The birds in Group 2 did not show a significant increase in body weight over the birds in Group 1; however, they did maintain their body weight despite the fact that they consistently laid more eggs.
plemented with a daily feeding of allmash pellets. There was no significant difference in gains in body weight between the two groups. Mortality was not abnormal and was approximately the same in both groups. REFERENCES
This investigation covering two production years for a total of 630 days with 1,200 Leghorns was carried out to determine whether a daily feeding of supplemental all-mash pellets was necessary to obtain maximum egg production when an all-mash laying ration was distributed by an automatic motor driven feeder. The results during the pullet laying year (365 days) showed significantly higher egg production when the supplemental all-mash pellets were fed. Even though the yearling laying period did not cover a full year, the egg production was again higher for the birds receiving the supplemental all-mash pellets. During the whole period of 630 days there was a greater feed intake, better feed conversion and lower feed cost per dozen eggs when the all-mash ration, distributed by an automatic feeder, was sup-
Dudley, F. J., 1932-1933. The degree of reliability of poultry feeding experiments. Harper Adams J. 18:260. Jensen, L. S., and J. McGinnis, 1952. A comparison of feeding pelleted and unpelleted diets containing different levels of alfalfa to laying hens. Poultry Sci. 31:307-310. Lee, C. E., S. W. Hamilton, C. L. Henry and M. E. Callanan, 1939. The effect of substituting an allmash and pellet ration for grain, mash and pellets on flock production, costs and returns. Poultry Sci. 18: 375-377. Lee, C. E., J. C. Scholes and C. L. Henry, 1944. The effect of "free choice" grain feeding on egg production, feed consumption, body weight and egg quality. Poultry Sci. 23:360-370. Lee, C. E., J. C. Scholes and C. L. Henry, 1949. The effect of "free choice" grain feeding on egg production and feed consumption. Poultry Sci. 28: 10-13. Morgan, R. B., and B. W. Heywang, 1941. A comparison of a pelleted and unpelleted all-mash diet for laying chickens. Poultry Sci. 20: 62-65. Morris, L., 1946. Pelleted versus unpelleted mash for laying hens. Poultry Sci. 25: 408.
Growth-Stimulating Factors in Alfalfa for Chicks 1 M. G. VAVICH, ANNE WERTZ 2 AND A. R. KEMMERER Department of Nutrition, College of Agriculture, University of Arizona (Received for publication September 22, 1952)
I
INVESTIGATIONS in the last several years have shown there are still some unidentified factors in feeds necessary for 1
This work was supported in part by a Grantin-Aid from the American Dehydrators Association, Kansas City, Missouri. 2 On leave from University of Massachusetts, Amherst, Massachusetts, Sept. 1951 to June 1952.
optimum nutrition. Only a few of these investigations, however, have been concerned with the existence of these factors in plant products. Carlson et al. (1949) and Menge et al. (1952) reported factors in yeast, and Cravens et al. (1951) factors in yeast and wheat bran that stimulate the growth of chicks. Bowland et al.
Downloaded from http://ps.oxfordjournals.org/ by Nathalia Oliveira on May 9, 2015
SUMMARY
therapy, at levels favorable to egg production, was reinitiated. 8. Body weight changes, while the radioiodine-treated hens received no thyroxin, were similar to body weight changes that took place in the control hens at the same time, and appear to be related to seasonal changes in weight rather than to the level of circulating thyroxin.
Brody, S., 1945. Bioenergetics and Growth. The Reinhold Publishing Corporation, New York. Kleiber, M., 1947. Body size and metabolic rate. Physiol. Revs. 27: 511-541. Marine, D., 1922. The present status of the functions of the thyroid gland. Physiol. Revs. 2: 521551. Schultze, A. B., and C. W. Turner, 1945. The determination of the rate of thyroxine secretion by certain domestic animals. Missouri Agr. Exp. Sta. Res. Bui. 392. Winchester, C. F., 1940. Seasonal endocrine and metabolic rhythms in the domestic fowl. Missouri Agr. Exp. Sta. Res. Bui. 315. Winchester, C. F., C. L. Comar and G. K. Davis, 1949. Thyroid destruction by I131, and replacement therapy. Science, 110: 302-304. Winchester, C. F., and G. K. Davis, 1952. Influence of thyroxin on growth of chickens. Poultry Sci. 31:31-34.
The Effect of Supplementary All-Mash. Pellets in the AllMash Feeding Program for Layers Using Automatic Feeders CLARENCE E. L E E , OLIN A. ROWOTH, C. L. HENRY AND JOSEPH PRESTO Poultry Research Division, The Beacon Milling Company, Inc., Cayuga, N. Y. (Received for publication September 22, 1952)
T ) R I O R to the use of automatic feeders, •*• many reports had been published on different feeding systems for layers. Several workers (Morgan and Heywang, 1941; Morris, 1946; and Jensen and McGinnis, 1952) have shown that no significant increase in egg production was obtained when a pelleted all-mash laying ration was compared with an unpelleted all-mash laying ration. Previous work by Lee, Hamilton, Henry and Callanan (1939) showed that egg production was lower and feed cost per dozen eggs was higher when an all-mash ration supplemented with pellets was compared with a grain, mash and pellet feeding program. Following this work, Lee, Scholes and Henry (1944, 1949), using Leghorn,
Rhode Island Red and Rhode Island Red X Barred Plymouth Rock crossbred layers, found that a controlled feeding program of grain, mash and pellets gave better egg production than free choice feeding of grain and mash. Since the advent of the automatic feeders and with present government price support on grains, unpublished work by this division has shown that an all-mash laying ration, distributed by an electric motor driven automatic feeder, supplemented by a daily (hand fed) feeding of all-mash pellets gave comparable egg production and a slightly lower feed cost per dozen eggs when compared with a controlled feeding program of grain, mash and pellets. With the popularity of automatic
Downloaded from http://ps.oxfordjournals.org/ by Nathalia Oliveira on May 9, 2015
REFERENCES Biester, H. E., and L. H. Schwarte, 1952. Diseases of Poultry, 3rd Ed. The Iowa State College Press, Ames, Iowa. Blaxter, K. L., E. P. Reineke, E. W. Crampton and W. E. Petersen, 1949. The role of thyroidal materials and of synthetic goitrogens in animal production and an appraisal of their practical use. J. Animal Sci. 8: 307-352.
429
430
C. E. L E E , 0. A. ROWOTH, C. L. HENRY AND J. PRESTO
EXPERIMENTAL
The Single Comb White Leghorn pullets used in this investigation were obtained as day old chicks from a commercial hatchery. These birds were brooded and ranged together and fed a grain and mash feeding program. At the end of the growing period these pullets were carefully selected and randomly divided into two groups of 600 birds. Each of the two groups of pullets was placed in identical 30'X52' pens. The two pens were divided by a feed room and were located on the ground floor of a two-story cinder block laying house. Each pen was equipped in the same manner, including an automatic electric motor driven feeder with 37 linear ft. of feeding space per 100 birds, based on the number of birds at the beginning of the experiment. Both groups of birds were fed a 16% protein commercial all-mash laying ration (actual average analysis about 17%) ad libitum using identical automatic feeders which operated continuously for 13 hours
daily except for a two-hour period in late afternoon. During this two-hour period the birds in group #2 received a supplementary hand feeding of the 16% protein all-mash laying ration in pellet form. During the winter months each pen received a daily morning feeding of two pounds of grain mixture per pen in order to stimulate working in the litter. This investigation covered the pullet laying year of 365 days and a yearling laying period of 265 days. It was necessary to end the yearling laying period June 30th in order to make room for early hatched pullets. Artificial lights were used in both pens during the fall, winter and early spring to give a 13 hour day, except for a 47 day molting period during the yearling laying year from November 15, 1951 to January 1, 1952. There was no culling during this investigation except for one bird out of each pen at the end of the pullet laying year. A representative number of birds were weighed weekly up to the age of maturity and biweekly thereafter, except during the molting period, in order to obtain the average body weight of the birds in each group. Egg production, feed consumption and mortality were recorded and summarized monthly. RESULTS AND DISCUSSION
Table 1 presents a summary of the pullet year from October 10, 1950 through October 9, 1951 (365 days). The summary includes data on the average number of eggs per bird (hen-day basis), details of feed consumption and costs, cost of feed per dozen eggs and percent mortality. According to the Harper Adams standard (Dudley, 1932) there is a significant difference in the egg production during the pullet laying year in favor of the birds in
Downloaded from http://ps.oxfordjournals.org/ by Nathalia Oliveira on May 9, 2015
feeders increasing, there is a great demand by commercial poultrymen for a simplified feeding program for layers which will effectively utilize this labor-saving device without sacrificing maximum egg production. Since the grain, mash and pellet feeding program is not well adapted for use with present automatic feeders, it was concluded that further research should be conducted with all-mash feeding systems. Previous unpublished work by this division using all-mash rations (hand fed) showed the necessity of supplemental pellets in order to obtain maximum egg production; therefore, this investigation was conducted to see if maximum egg production could be obtained by eliminating the supplementary feeding of allmash pellets when the all-mash ration was fed by means of an automatic feeder.
SUPPLEMENTARY PELLETS FOR LAYERS TABLE 1.—Summary of data—pullet laying year
Number of birds Number eggs per bird Percent production Pounds mash per bird Pounds pellet per bird Pounds grain per bird Total feed consumed per bird (lbs.) Feed cost per bird—Total Feed per dozen eggs Cost of feed per dozen eggs Percent mortality
Group 1
Group 2
600 257.15 70.45 112.92 0.00 0.81
600 279.92 76.69 85.95 33.96 0.82
113.73 $5.80 5.31 $0,271 11.34
120.73 $6.19 5.18 $0,265 10.83
Group 2 receiving the daily supplementary feeding of all-mash pellets (hand fed). The birds in this group laid an average of 22.77 more eggs per bird than the birds in Group 1 receiving no pellets. The average feed consumption for the birds receiving pellets was 7 pounds greater per bird than the birds in Group 1; however, these birds (with pellets) showed a slightly better feed conversion. The feed cost per dozen eggs was 0.6 cent less for Group 2 despite the fact that these birds consumed more feed and the pellets were priced $1.50 (pelleting charge) TABLE 2.—Summary of data—yearling laying period (265 days only, including molt)
Number of birds Number eggs per bird Percent production Pounds mash per bird Pounds pellets per bird Pounds grain per bird Total feed consumed per bird (lbs.) Feed cost per bird—Total Feed per dozen eggs Cost of feed per dozen eggs Percent mortality
Group 1
Group 2
531 126.60 47.77 78.54 0.00 0.32
534 141.30 53.23 70.42 14.74 0.32
78.86 $3.92 7.47 $0,372 7.90
85.48 $4.25 7.26 $0,361 9.37
Stock used: S.C. White Leghorns. Hatched April 13, 1950. Time of experiment: October 10, 1951 through June 30, 1952 (265 days including a 47 day molting period Nov. 15, 1951 to Jan. 1, 1952).
higher per ton than the mash. Table 2 presents a summary of the yearling laying period from October 10, 1951 to June 30, 1952 (265 days including a 47 day molting period). As was the case in the pullet laying year the birds in Group 2 receiving the daily supplementary feeding of pellets (hand fed) ate more feed, and produced more eggs with a better feed conversion. These data show that the birds in Group 2 consumed an average of 6.62 pounds of additional feed per bird and laid an average of 14.70 eggs more per bird than the birds in Group 1. The feed cost per dozen eggs favored the birds in Group 2 by 1.1 cents per dozen eggs. It was unfortunate that this experiment had to be terminated before the completion of the yearling laying year since the birds in Group 2 were laying approximately 65% when the experiment had to be discontinued, while the birds receiving no pellets were beginning to molt and were laying only approximately 40%. During both laying years the mortality was not abnormal and was mainly due to leukosis. By comparing the weight of the same volume of the pellets and mash it was found that the density of the pellets was 1.214 greater than the mash. Using this figure to calculate the comparative feed consumption of the two groups on a volume basis, it was found that the average volume of feed consumed by each group was almost identical. The graph in Figure 1 shows the egg production by eggs per bird per month for the complete period of 630 days covering both laying years. This graph shows that the group receiving the supplementary pellets had a higher peak egg production and consistently laid more eggs during both laying years except during the molting period.
Downloaded from http://ps.oxfordjournals.org/ by Nathalia Oliveira on May 9, 2015
Stock used: S.C. White Leghorns. Hatched April 13, 1950. Time of Experiment: October 10, 1950 through October 9, 1951 (365 days).
431
432
C. E. L E E , 0. A. ROWOTH, C. L. HENRY AND J. PRESTO
iiso
nsi
Dec. Jan.
fcV. Haf.
fter.
rAay vta
nsi dorAVs
i1SO-H52L
FIG. 1. Egg production for 630 days.
5.5 +
5.0- •
f.5-> Group 1 Group t Oct.10-31 N-v. T>*«. J » * . F«V
Nar.
Ap
May
June
July
M<,-AV»
Au*
S« r +.
OcT.
N°».
1150 - m 2
FIG. 2. Average monthly body weight.
Dec. J a t .
F«W.
(No
Pellets)
(Witt, Pelt.ls) Ma«*. A p r . h a y
Ja
Downloaded from http://ps.oxfordjournals.org/ by Nathalia Oliveira on May 9, 2015
Osfc. 10-31 Nov. De«.. Jan. F«\>. /Aar. Af». M»» O w My fVj. S«rV. OcV. N.v.
433
GROWTH FACTOR IN ALFALFA
The graph in Figure 2 shows the average monthly body weight of the birds in the two groups, except during the molting period. The birds in Group 2 did not show a significant increase in body weight over the birds in Group 1; however, they did maintain their body weight despite the fact that they consistently laid more eggs.
plemented with a daily feeding of allmash pellets. There was no significant difference in gains in body weight between the two groups. Mortality was not abnormal and was approximately the same in both groups. REFERENCES
This investigation covering two production years for a total of 630 days with 1,200 Leghorns was carried out to determine whether a daily feeding of supplemental all-mash pellets was necessary to obtain maximum egg production when an all-mash laying ration was distributed by an automatic motor driven feeder. The results during the pullet laying year (365 days) showed significantly higher egg production when the supplemental all-mash pellets were fed. Even though the yearling laying period did not cover a full year, the egg production was again higher for the birds receiving the supplemental all-mash pellets. During the whole period of 630 days there was a greater feed intake, better feed conversion and lower feed cost per dozen eggs when the all-mash ration, distributed by an automatic feeder, was sup-
Dudley, F. J., 1932-1933. The degree of reliability of poultry feeding experiments. Harper Adams J. 18:260. Jensen, L. S., and J. McGinnis, 1952. A comparison of feeding pelleted and unpelleted diets containing different levels of alfalfa to laying hens. Poultry Sci. 31:307-310. Lee, C. E., S. W. Hamilton, C. L. Henry and M. E. Callanan, 1939. The effect of substituting an allmash and pellet ration for grain, mash and pellets on flock production, costs and returns. Poultry Sci. 18: 375-377. Lee, C. E., J. C. Scholes and C. L. Henry, 1944. The effect of "free choice" grain feeding on egg production, feed consumption, body weight and egg quality. Poultry Sci. 23:360-370. Lee, C. E., J. C. Scholes and C. L. Henry, 1949. The effect of "free choice" grain feeding on egg production and feed consumption. Poultry Sci. 28: 10-13. Morgan, R. B., and B. W. Heywang, 1941. A comparison of a pelleted and unpelleted all-mash diet for laying chickens. Poultry Sci. 20: 62-65. Morris, L., 1946. Pelleted versus unpelleted mash for laying hens. Poultry Sci. 25: 408.
Growth-Stimulating Factors in Alfalfa for Chicks 1 M. G. VAVICH, ANNE WERTZ 2 AND A. R. KEMMERER Department of Nutrition, College of Agriculture, University of Arizona (Received for publication September 22, 1952)
I
INVESTIGATIONS in the last several years have shown there are still some unidentified factors in feeds necessary for 1
This work was supported in part by a Grantin-Aid from the American Dehydrators Association, Kansas City, Missouri. 2 On leave from University of Massachusetts, Amherst, Massachusetts, Sept. 1951 to June 1952.
optimum nutrition. Only a few of these investigations, however, have been concerned with the existence of these factors in plant products. Carlson et al. (1949) and Menge et al. (1952) reported factors in yeast, and Cravens et al. (1951) factors in yeast and wheat bran that stimulate the growth of chicks. Bowland et al.
Downloaded from http://ps.oxfordjournals.org/ by Nathalia Oliveira on May 9, 2015
SUMMARY