- Email: [email protected]
Intermittent Feeding of Vitamin A to Chickens1
MANAGEMENT AND EGG PRODUCTION
versus confinement rearing on egg quality. Poultry Sci. 36: 1146-1147. Pepper, W. F., S. J. Slinger and J. D. Summers, 1957. Influence of method of rearing on the performance of pullets in the laying house. Poultry Sci. 36: 1148. Singsen, E. P., L. D. Matterson, A. Kozeff and L. Stinton, 1954. The effect of feeding high and low efficiency rations to growing pullets on
385
their subsequent laying performance. Poultry Sci. 33: 1081. Taylor, J. N., B. B. Bailey and J. H. Quisenberry, 1957. Comparison of certain pullet rearing and feeding programs for egg production. Poultry Sci. 36: 1162. Titus, Harry W., 1955. The Scientific Feeding of Chickens. 2nd Ed. The Interstate, Danville, 111. Pp. 258-261.
W. H. HASTINGS, PAUL E. SANFORD AND C. R.
CREGER2
Kansas State College, Manhattan, Kansas (Received for publication August 1, 1958)
Under conditions of insufficient mixing, segregation of materials after mixing, inaccurate weighing or calculations, or selection by livestock, Bloom and Livesey (19S3) suggest that two factors assist in overcoming the expected adverse biological effects of non-uniformity, (a) the use of sufficiently liberal amounts of microingredients to balance an occasional deficiency, and (b) the ability of livestock to store nutrients in body tissues or function normally for short periods of reduced intake. Such thinking may be shared by feed manufacturers although not often expressed in advertising literature. It is known that essential amino acids must be present in the ration at all times for both growth and maintenance, because there are no storage depots on which to draw for a supply in case of temporary blood deficiencies. However, vitamin A, which is added in microingredient quanti1 Contribution No. 304, Department of Flour ties, has storage depots in liver and fat tisand Feed Milling Industries, and No. 243, Depart- sues. This nutrient was chosen to be fed ment of Poultry Husbandry, Kansas Agricultural continuously and intermittently to simuExperiment Station, Manhattan. late possible milling conditions in which a 2 Present address: Department of Poultry Husproper formula was used, but the resultant bandry, Texas A. & M. College, College Station, product was not uniformly distributed. Texas. INTRODUCTION
A
T THE start of a research project on • mechanical distribution of microingredients in formula feeds, it was recognized that the proportion obtained in a batch mixer was not necessarily constant in all increments of feed weight during conveying, bagging and transportation to the feeder and in the selection of feed by the animal. The question was asked, "Is the biological response to a nutrient sufficiently sensitive to justify the effort and expense involved in preparing a ration which will supply in each daily portion consumed the exact formula of ingredients added on a batch basis?" In other words, can an animal eat an excess of some nutrients one day and less the next day, or for other intermittent time schedules, and over a given period of growth and production, maintain expected performance and feed conversion?
Downloaded from http://ps.oxfordjournals.org/ at Dalhousie University on June 20, 2015
Intermittent Feeding of Vitamin A to Chickens 1
386
W. H. HASTINGS, P. E. SANFORD AND C. R. CREGER EXPERIMENTAL PROCEDURE
Source of vitamin A
Feeding schedule
Average Feed conweight version
Crystalline
Continuous
(grams) 1,390
2.79
Dehydrated Alfalfa
Continuous
1,318
2.66
Crystalline
1 day with 1 day without
1,304
2.82
Crystalline
3 days with 3 days without
1,317
3.3
Dehydrated Alfalfa
3 days with 3 days without
1,327
3.15
Straight-run day-old chicks (first generation Cornish X Arbor Acres White Rock) were used. They were randomized into 11 lots and placed in test pens, 10 with 35 chicks per lot, and the 11th with 27 chicks used as a negative control. All chicks when received were weighed, wing-banded and vaccinated intranasally for Newcastle disease. The usual husbandry conditions of feed and water hopper space and temperature were observed for all groups during the experimental feeding period. The formula (Table 2 ), was modified from that of previous laboratory rations and manufactured utilizing commercial milling equipment. Sufficient basal ration was made for the entire test period and sacked off in 50-pound paper bags. Rations containing vitamin A were made up at the Poultry Farm as needed in 50-pound lots, using carefully tested vitamin A material stored at 36°F. The chemical material had 11,000 I.U. per gram and the dehydrated alfalfa meal contained 530 I.U. per gram. Duplicate pens were used to include vitamin A as a chemical ester (a) at levels of 1,200 I.U. per pound of feed continuously and (b) at 2,400 I.U. per pound of feed for three days followed by none for three days. Duplicate pens were also used to include
Downloaded from http://ps.oxfordjournals.org/ at Dalhousie University on June 20, 2015
Results of exploratory work are included as experimental in planning the procedure which was reported in the following sections of this paper. Three lots of twenty sexed cockerels, broiler strain crosses, were raised in batteries to 8 weeks as a Poultry Nutrition class project. One lot received a basal ration lacking known sources of vitamin A, but complete in all other known nutrients. Another lot received the same ration plus 2,000 I.U. vitamin A per pound. A third lot received, alternately, a daily ration containing 4,000 I.U. vitamin A and the basal ration. Birds which died in Lot 1 were posted and vitamin A deficiency confirmed. Growth rate in the other two lots and total weight at 8 weeks were very nearly equal. Feed conversion in the lot fed vitamin A continuously was better than in the lot fed intermittently. The test was repeated in brooder and developing batteries with 6 lots of chickens, as a class project for another course, Animal Nurition Techniques, Department of Chemistry. Two lots were fed 1,200 I.U. vitamin A per pound continuously, one using alfalfa meal as the nutrient source, the other using the pure chemical palmitate. Three lots were fed alternately a ration containing 2,400 I.U. per pound and the basal ration. One group received the basal ration continuously. Feed was mixed weekly for this test using vitamin A material from cold storage. Eight weeks' average growth and feed conversion are shown in Table 1. Since the work was not done in duplicate, the data were not subjected to statistical analysis. Differences in growth in the lots were not considered significant. Feed conversion was best in lots receiving continuous levels of vitamin A. The test was repeated in a brooder house using pens which had previously been determined to have like environment.
TABLE 1.—Average 8-weeks' weights and feed conversion of sexed male broiler strain cross chicks fed continuous and intermittent levels of vitamin A
387
INTERMITTENT FEEDING OF VITAMIN A TABLE 2.—Basal ration used for intermittent feeding of vitamin A Percent
Ground white corn Ground grain sorghums Soybean oil meal (44% protein) Dried skim milk Brewers' yeast Steamed bone meal Limestone Iodized salt Cottonseed oil B-complex suppl." Antibiotic suppl. b Vitamin D 3 (3,000 I.C.U./g.) Sulfaquinoxaline (pure) Premix0
29.5 29.5 31.2 2.0 2.0 2.0 1.0 0.5 0.7 0.25 0.50 0.05 0.025 0.575
a Contains 2 g. riboflavin, 9 g. niacin, 4 g. pantothenic acid, and 90 g. choline chloride per pound. b Contains 1.8 g. chlortetracycline and 1.8 mg. B12 activity per pound. c Premix supplied the following per ton of ration: 0.9 mgs. menadione, 200 gms. MnSQi, 72 gms. FeCOs, 7.2 gms. CuOH, 0.25 gms. ZnC0 3 0.72 gms. CoC0 3 .
RESULTS AND DISCUSSION
Testing for variance between mean cockerel weights, using Fisher's l.s.d. (least significant difference) as a multiple F test, a significant difference was found between each lot or duplicated lot when arranged in the order shown in Table 4. No signifi-
pro-vitamin A material from dehydrated alfalfa meal on exactly the same basis. Ad-
TABLE 3.—Weight, feed consumption and feed conversion for chicks eight weeks inldfed continuous and intermittent levels of vitamin A Feed consumption Source of vitamin A
Feeding schedule
Final No. of chicks
Basal
Basal-(-vitamin A
Weighted avFeed erage per Jlot conversion
Crystalline
Continuous
34
lbs. None
lbs. 194.9
gms. 1,224
2.08
Crystalline
Duplicate
34
None
189.4
1,205
2.10
Crystalline
3 days with 3 days without
35
80
110.8
1,187
2.06
Crystalline
Duplicate
35
80.7
106
1,183
2.05
Crystalline
6 days with 6 days without
34
84
124.6
1,227
2.23
Alfalfa Meal
Continuous
35
None
201.5
1,162
2.23
Alfalfa Meal
Duplicate
34
None
187.9
1,164
2.13
Alfalfa Meal 3 days with 3 days without
33
85
107
1,147
2.32
Alfalfa Meal
Duplicate
35
85
114.3
1,112
2.30
Alfalfa Meal
6 days with 6 days without
34
89.8
126
1,154
2.46
Downloaded from http://ps.oxfordjournals.org/ at Dalhousie University on June 20, 2015
Ingredient
ditional single pens were used for feeding the chemical ester and the pro-vitamin material on a 6-day alternate schedule. Group weights and feed consumption were recorded at 2-week intervals except that at the 8 th week, birds were weighed individually. Separate cans were used to store basal rations and vitamin A-containing ration. Total feed per lot was obtained by adding all feed weighed out and subtracting feed weighed back on the day of weighing birds. Data for growth, feed consumption and feed conversion are shown in Table 3.
388
W. H. HASTINGS, P. E. SANFORD AND C. R. CREGEK
TABLE 4.—Decreasing order of 8-weeks' weights for cockerels fed vitamin A continuously and intermittently No. Av. of weight chicks (grams)
Source of vitamin A
Feeding schedule
1&2
Crystalline
Continuous
37
1,373.5
5
Crystalline
6 days with 6 days without
21
1,343.3
3 days with 3 days without
38
1,308.7
19
1,266.9
6 & 7 Alfalfa Meal Continuous
39
1,235.6
8 & 9 Alfalfa Meal 3 days with 3 days without
36
1,207.2
3 & 4 Crystalline 10
Alfalfa Meal
6 days with 6 days without
cant difference was found between mean pullet weights by the F test, either within duplicates on a diet or between diets. A weight difference in favor of continuous feeding of the vitamin was found between the average of all birds on continuous feeding and those having intermittent feeding with the 3-days-with-and-3-days-without schedule. However, no difference was found between lots fed the vitamin continuously and the 6-day alternate schedule. This makes it impossible to draw conclusions for weight differences due to any feeding schedule. If a real difference exists, it may require a larger number of birds than used in this work to show it statistically. Comparing the male weights in lots 1 through 5 with those in lots 6 through 10, (Table 4) it can be statistically shown that under the conditions of this experiment, birds receiving chemical vitamin A had better growth than those fed the same nutrient from dehydrated alfalfa meal. The alfalfa product was used at approximately 0.5% in the total ration and its depressing effect, if any, or its undigestible fiber content, would hardly influence growth results. Records of total feed consumption per lot ruled out the possibility that palat-
Downloaded from http://ps.oxfordjournals.org/ at Dalhousie University on June 20, 2015
Lot No.
ability was a factor in growth results. In the analysis of the alfalfa material for carotene, it was found that about 60% was trans-configuration and the rest stereochemical isomers which, in rats, have proved less biologically active than all-trans-beta-carotene (Embree, 1946; and Deuel et al., 1945). However, this relationship has not been proved to exist for birds, and it may be concluded that there is no distinction between vitamin A and its pro-vitamins on a calculated unit basis as determined for this experiment. No precautions were taken with the alfalfa-containing ration to prevent oxidation and sufficient vitamin A activity might have been lost to depress growth. The first 50-pound mixture carried the birds to the middle of the third week, and there is a possibility that lower gains were due to destruction of pro-vitamin A in rations during early growth and that the birds were unable to recover from this during the remaining time on test. The 4th week growth did not reflect the differences which developed later between the chemical and pro-vitamin material. Scott (1958) and Castano et al (1951) found in experimental work that the vitamin A requirement of starting chicks is no higher than 600 I.U. per pound which is considerably less than the levels used in this study. The alfalfa material would have to lose 50% of its initial potency to be considered deficient in producing optimum growth. Feed consumption data could not be analyzed statistically because there were no individual bird consumption records. Except for the similar feed conversion of the duplicated lots fed crystalline vitamin A continuously and those fed the same material intermittently for 3 days, there was a trend for better conversion with continuous levels. Average feed conversion for all lots fed crystalline vitamin A was better than those fed pro-vitamin A material. It was noted that
INTERMITTENT FEEDING OF VITAMIN A
SUMMARY
Intermittent feeding of vitamin A, as compared with feeding the nutrient continuously, resulted in no significant difference in chick growth. Growth was significantly better in lots receiving chemical vitamin A material than in those lots receiving dehy-
drated alfalfa meal. Feed conversion, in general, was better with continuous vitamin A feeding. More vitamin A-containing feed was consumed than the basal ration even though each was offered for the same length of time. ACKNOWLEDGMENT
The authors wish to thank Dr. Donald B. Parrish for tested vitamin A materials, for animal laboratory space and technical assistance in planning this research. REFERENCES Bloom, C , and E. F. Livesay, 1953. Particle sizes for additives to animal foods. Manufacturing Chemist, 24: 371-375. Castano, F. F., R. V. Boucher and E. W. Callenbach, 1951. Utilization by the chick of vitamin A from different sources. I. Crystalline carotene, crystalline vitamin A acetate, and "black cod" liver oil. J. Nutrition, 4 5 : 131-141. Deuel, H. J., Jr., E. Sumner, C. Johnston, A. Polgar and L. Zechmeister, 1945. Stereochemical configuration and pro-vitamin A activity. III. All-trans-alpha-carotene and neo-alpha-carotene U. Arch. Biochem. 6: 157-161. Embree, N., 1946. Recent advances in the chemistry and nutrition of the fat-soluble vitamins. J. Am. Oil Chem. Soc. 23: 305-310. Scott, M. L., 1958. Vitamins in poultry nutrition. Feed age, 8: 22-29.
NEWS AND NOTES (Continued from page 372) EASTERN INTERCOLLEGIATE JUDGING and two trophies, one given by the Eastern InterAt the 34th Eastern Intercollegiate Poultry collegiate Poultry Judging Contest, and the other Judging Contest held at Rutgers University, Noby the Pennsylvania Farm Bureau. vember 22, 1958, the University of Maryland Second high individual was Carl Rice of Corteam won first place with 3123 points, out of a nell University with 1073 points, and third high possible 3600. The University of Connecticut team individual was Daniel Daly of the University of was second with 3028 points, and the Cornell Uni- Maryland with 1058 points. versity team was third with 3005 points. Eight A. Kish of the Pennsylvania Farm Bureau was teams competed. Chairman of the event, and J. F. Bauermann of Rutgers University was responsible for the local The members of the University of Maryland arrangements and facilities. team were Daniel W. Daly, James H. Comings and At the banquet, a gift certificate was presented Robert D. Noren. to Professor Luther Banta of the University of The individual winner was Robert Powers of Massachusetts in recognition of his forty years as a the University of Connecticut with 1080 points of a possible 1200. He received a prize of $35.00, coach of the University poultry judging teams. (Continued on page 394)
Downloaded from http://ps.oxfordjournals.org/ at Dalhousie University on June 20, 2015
approximately 60% of the total feed consumed contained vitamin A although it was presented to the birds only 50% of the time. Either the basal ration was unpalatable or some appetite stimulant was present in the vitamin additive which, expressed as growth, over-balanced the possible depressing effects of the basal ration during periods of its consumption. An examination of individual growth data indicated that there was no reason to suspect non-homogenous variance within lots which might have been caused by poor mixing. It may be concluded that the chemical vitamin A and the alfalfa meal materials added at the levels of approximately 11 and 227 grams per 100 pounds respectively, were distributed uniformly in all rations. If distribution of vtiamin A were questioned, the chemical material would more likely lack uniformity than the alfalfa meal.
389
versus confinement rearing on egg quality. Poultry Sci. 36: 1146-1147. Pepper, W. F., S. J. Slinger and J. D. Summers, 1957. Influence of method of rearing on the performance of pullets in the laying house. Poultry Sci. 36: 1148. Singsen, E. P., L. D. Matterson, A. Kozeff and L. Stinton, 1954. The effect of feeding high and low efficiency rations to growing pullets on
385
their subsequent laying performance. Poultry Sci. 33: 1081. Taylor, J. N., B. B. Bailey and J. H. Quisenberry, 1957. Comparison of certain pullet rearing and feeding programs for egg production. Poultry Sci. 36: 1162. Titus, Harry W., 1955. The Scientific Feeding of Chickens. 2nd Ed. The Interstate, Danville, 111. Pp. 258-261.
W. H. HASTINGS, PAUL E. SANFORD AND C. R.
CREGER2
Kansas State College, Manhattan, Kansas (Received for publication August 1, 1958)
Under conditions of insufficient mixing, segregation of materials after mixing, inaccurate weighing or calculations, or selection by livestock, Bloom and Livesey (19S3) suggest that two factors assist in overcoming the expected adverse biological effects of non-uniformity, (a) the use of sufficiently liberal amounts of microingredients to balance an occasional deficiency, and (b) the ability of livestock to store nutrients in body tissues or function normally for short periods of reduced intake. Such thinking may be shared by feed manufacturers although not often expressed in advertising literature. It is known that essential amino acids must be present in the ration at all times for both growth and maintenance, because there are no storage depots on which to draw for a supply in case of temporary blood deficiencies. However, vitamin A, which is added in microingredient quanti1 Contribution No. 304, Department of Flour ties, has storage depots in liver and fat tisand Feed Milling Industries, and No. 243, Depart- sues. This nutrient was chosen to be fed ment of Poultry Husbandry, Kansas Agricultural continuously and intermittently to simuExperiment Station, Manhattan. late possible milling conditions in which a 2 Present address: Department of Poultry Husproper formula was used, but the resultant bandry, Texas A. & M. College, College Station, product was not uniformly distributed. Texas. INTRODUCTION
A
T THE start of a research project on • mechanical distribution of microingredients in formula feeds, it was recognized that the proportion obtained in a batch mixer was not necessarily constant in all increments of feed weight during conveying, bagging and transportation to the feeder and in the selection of feed by the animal. The question was asked, "Is the biological response to a nutrient sufficiently sensitive to justify the effort and expense involved in preparing a ration which will supply in each daily portion consumed the exact formula of ingredients added on a batch basis?" In other words, can an animal eat an excess of some nutrients one day and less the next day, or for other intermittent time schedules, and over a given period of growth and production, maintain expected performance and feed conversion?
Downloaded from http://ps.oxfordjournals.org/ at Dalhousie University on June 20, 2015
Intermittent Feeding of Vitamin A to Chickens 1
386
W. H. HASTINGS, P. E. SANFORD AND C. R. CREGER EXPERIMENTAL PROCEDURE
Source of vitamin A
Feeding schedule
Average Feed conweight version
Crystalline
Continuous
(grams) 1,390
2.79
Dehydrated Alfalfa
Continuous
1,318
2.66
Crystalline
1 day with 1 day without
1,304
2.82
Crystalline
3 days with 3 days without
1,317
3.3
Dehydrated Alfalfa
3 days with 3 days without
1,327
3.15
Straight-run day-old chicks (first generation Cornish X Arbor Acres White Rock) were used. They were randomized into 11 lots and placed in test pens, 10 with 35 chicks per lot, and the 11th with 27 chicks used as a negative control. All chicks when received were weighed, wing-banded and vaccinated intranasally for Newcastle disease. The usual husbandry conditions of feed and water hopper space and temperature were observed for all groups during the experimental feeding period. The formula (Table 2 ), was modified from that of previous laboratory rations and manufactured utilizing commercial milling equipment. Sufficient basal ration was made for the entire test period and sacked off in 50-pound paper bags. Rations containing vitamin A were made up at the Poultry Farm as needed in 50-pound lots, using carefully tested vitamin A material stored at 36°F. The chemical material had 11,000 I.U. per gram and the dehydrated alfalfa meal contained 530 I.U. per gram. Duplicate pens were used to include vitamin A as a chemical ester (a) at levels of 1,200 I.U. per pound of feed continuously and (b) at 2,400 I.U. per pound of feed for three days followed by none for three days. Duplicate pens were also used to include
Downloaded from http://ps.oxfordjournals.org/ at Dalhousie University on June 20, 2015
Results of exploratory work are included as experimental in planning the procedure which was reported in the following sections of this paper. Three lots of twenty sexed cockerels, broiler strain crosses, were raised in batteries to 8 weeks as a Poultry Nutrition class project. One lot received a basal ration lacking known sources of vitamin A, but complete in all other known nutrients. Another lot received the same ration plus 2,000 I.U. vitamin A per pound. A third lot received, alternately, a daily ration containing 4,000 I.U. vitamin A and the basal ration. Birds which died in Lot 1 were posted and vitamin A deficiency confirmed. Growth rate in the other two lots and total weight at 8 weeks were very nearly equal. Feed conversion in the lot fed vitamin A continuously was better than in the lot fed intermittently. The test was repeated in brooder and developing batteries with 6 lots of chickens, as a class project for another course, Animal Nurition Techniques, Department of Chemistry. Two lots were fed 1,200 I.U. vitamin A per pound continuously, one using alfalfa meal as the nutrient source, the other using the pure chemical palmitate. Three lots were fed alternately a ration containing 2,400 I.U. per pound and the basal ration. One group received the basal ration continuously. Feed was mixed weekly for this test using vitamin A material from cold storage. Eight weeks' average growth and feed conversion are shown in Table 1. Since the work was not done in duplicate, the data were not subjected to statistical analysis. Differences in growth in the lots were not considered significant. Feed conversion was best in lots receiving continuous levels of vitamin A. The test was repeated in a brooder house using pens which had previously been determined to have like environment.
TABLE 1.—Average 8-weeks' weights and feed conversion of sexed male broiler strain cross chicks fed continuous and intermittent levels of vitamin A
387
INTERMITTENT FEEDING OF VITAMIN A TABLE 2.—Basal ration used for intermittent feeding of vitamin A Percent
Ground white corn Ground grain sorghums Soybean oil meal (44% protein) Dried skim milk Brewers' yeast Steamed bone meal Limestone Iodized salt Cottonseed oil B-complex suppl." Antibiotic suppl. b Vitamin D 3 (3,000 I.C.U./g.) Sulfaquinoxaline (pure) Premix0
29.5 29.5 31.2 2.0 2.0 2.0 1.0 0.5 0.7 0.25 0.50 0.05 0.025 0.575
a Contains 2 g. riboflavin, 9 g. niacin, 4 g. pantothenic acid, and 90 g. choline chloride per pound. b Contains 1.8 g. chlortetracycline and 1.8 mg. B12 activity per pound. c Premix supplied the following per ton of ration: 0.9 mgs. menadione, 200 gms. MnSQi, 72 gms. FeCOs, 7.2 gms. CuOH, 0.25 gms. ZnC0 3 0.72 gms. CoC0 3 .
RESULTS AND DISCUSSION
Testing for variance between mean cockerel weights, using Fisher's l.s.d. (least significant difference) as a multiple F test, a significant difference was found between each lot or duplicated lot when arranged in the order shown in Table 4. No signifi-
pro-vitamin A material from dehydrated alfalfa meal on exactly the same basis. Ad-
TABLE 3.—Weight, feed consumption and feed conversion for chicks eight weeks inldfed continuous and intermittent levels of vitamin A Feed consumption Source of vitamin A
Feeding schedule
Final No. of chicks
Basal
Basal-(-vitamin A
Weighted avFeed erage per Jlot conversion
Crystalline
Continuous
34
lbs. None
lbs. 194.9
gms. 1,224
2.08
Crystalline
Duplicate
34
None
189.4
1,205
2.10
Crystalline
3 days with 3 days without
35
80
110.8
1,187
2.06
Crystalline
Duplicate
35
80.7
106
1,183
2.05
Crystalline
6 days with 6 days without
34
84
124.6
1,227
2.23
Alfalfa Meal
Continuous
35
None
201.5
1,162
2.23
Alfalfa Meal
Duplicate
34
None
187.9
1,164
2.13
Alfalfa Meal 3 days with 3 days without
33
85
107
1,147
2.32
Alfalfa Meal
Duplicate
35
85
114.3
1,112
2.30
Alfalfa Meal
6 days with 6 days without
34
89.8
126
1,154
2.46
Downloaded from http://ps.oxfordjournals.org/ at Dalhousie University on June 20, 2015
Ingredient
ditional single pens were used for feeding the chemical ester and the pro-vitamin material on a 6-day alternate schedule. Group weights and feed consumption were recorded at 2-week intervals except that at the 8 th week, birds were weighed individually. Separate cans were used to store basal rations and vitamin A-containing ration. Total feed per lot was obtained by adding all feed weighed out and subtracting feed weighed back on the day of weighing birds. Data for growth, feed consumption and feed conversion are shown in Table 3.
388
W. H. HASTINGS, P. E. SANFORD AND C. R. CREGEK
TABLE 4.—Decreasing order of 8-weeks' weights for cockerels fed vitamin A continuously and intermittently No. Av. of weight chicks (grams)
Source of vitamin A
Feeding schedule
1&2
Crystalline
Continuous
37
1,373.5
5
Crystalline
6 days with 6 days without
21
1,343.3
3 days with 3 days without
38
1,308.7
19
1,266.9
6 & 7 Alfalfa Meal Continuous
39
1,235.6
8 & 9 Alfalfa Meal 3 days with 3 days without
36
1,207.2
3 & 4 Crystalline 10
Alfalfa Meal
6 days with 6 days without
cant difference was found between mean pullet weights by the F test, either within duplicates on a diet or between diets. A weight difference in favor of continuous feeding of the vitamin was found between the average of all birds on continuous feeding and those having intermittent feeding with the 3-days-with-and-3-days-without schedule. However, no difference was found between lots fed the vitamin continuously and the 6-day alternate schedule. This makes it impossible to draw conclusions for weight differences due to any feeding schedule. If a real difference exists, it may require a larger number of birds than used in this work to show it statistically. Comparing the male weights in lots 1 through 5 with those in lots 6 through 10, (Table 4) it can be statistically shown that under the conditions of this experiment, birds receiving chemical vitamin A had better growth than those fed the same nutrient from dehydrated alfalfa meal. The alfalfa product was used at approximately 0.5% in the total ration and its depressing effect, if any, or its undigestible fiber content, would hardly influence growth results. Records of total feed consumption per lot ruled out the possibility that palat-
Downloaded from http://ps.oxfordjournals.org/ at Dalhousie University on June 20, 2015
Lot No.
ability was a factor in growth results. In the analysis of the alfalfa material for carotene, it was found that about 60% was trans-configuration and the rest stereochemical isomers which, in rats, have proved less biologically active than all-trans-beta-carotene (Embree, 1946; and Deuel et al., 1945). However, this relationship has not been proved to exist for birds, and it may be concluded that there is no distinction between vitamin A and its pro-vitamins on a calculated unit basis as determined for this experiment. No precautions were taken with the alfalfa-containing ration to prevent oxidation and sufficient vitamin A activity might have been lost to depress growth. The first 50-pound mixture carried the birds to the middle of the third week, and there is a possibility that lower gains were due to destruction of pro-vitamin A in rations during early growth and that the birds were unable to recover from this during the remaining time on test. The 4th week growth did not reflect the differences which developed later between the chemical and pro-vitamin material. Scott (1958) and Castano et al (1951) found in experimental work that the vitamin A requirement of starting chicks is no higher than 600 I.U. per pound which is considerably less than the levels used in this study. The alfalfa material would have to lose 50% of its initial potency to be considered deficient in producing optimum growth. Feed consumption data could not be analyzed statistically because there were no individual bird consumption records. Except for the similar feed conversion of the duplicated lots fed crystalline vitamin A continuously and those fed the same material intermittently for 3 days, there was a trend for better conversion with continuous levels. Average feed conversion for all lots fed crystalline vitamin A was better than those fed pro-vitamin A material. It was noted that
INTERMITTENT FEEDING OF VITAMIN A
SUMMARY
Intermittent feeding of vitamin A, as compared with feeding the nutrient continuously, resulted in no significant difference in chick growth. Growth was significantly better in lots receiving chemical vitamin A material than in those lots receiving dehy-
drated alfalfa meal. Feed conversion, in general, was better with continuous vitamin A feeding. More vitamin A-containing feed was consumed than the basal ration even though each was offered for the same length of time. ACKNOWLEDGMENT
The authors wish to thank Dr. Donald B. Parrish for tested vitamin A materials, for animal laboratory space and technical assistance in planning this research. REFERENCES Bloom, C , and E. F. Livesay, 1953. Particle sizes for additives to animal foods. Manufacturing Chemist, 24: 371-375. Castano, F. F., R. V. Boucher and E. W. Callenbach, 1951. Utilization by the chick of vitamin A from different sources. I. Crystalline carotene, crystalline vitamin A acetate, and "black cod" liver oil. J. Nutrition, 4 5 : 131-141. Deuel, H. J., Jr., E. Sumner, C. Johnston, A. Polgar and L. Zechmeister, 1945. Stereochemical configuration and pro-vitamin A activity. III. All-trans-alpha-carotene and neo-alpha-carotene U. Arch. Biochem. 6: 157-161. Embree, N., 1946. Recent advances in the chemistry and nutrition of the fat-soluble vitamins. J. Am. Oil Chem. Soc. 23: 305-310. Scott, M. L., 1958. Vitamins in poultry nutrition. Feed age, 8: 22-29.
NEWS AND NOTES (Continued from page 372) EASTERN INTERCOLLEGIATE JUDGING and two trophies, one given by the Eastern InterAt the 34th Eastern Intercollegiate Poultry collegiate Poultry Judging Contest, and the other Judging Contest held at Rutgers University, Noby the Pennsylvania Farm Bureau. vember 22, 1958, the University of Maryland Second high individual was Carl Rice of Corteam won first place with 3123 points, out of a nell University with 1073 points, and third high possible 3600. The University of Connecticut team individual was Daniel Daly of the University of was second with 3028 points, and the Cornell Uni- Maryland with 1058 points. versity team was third with 3005 points. Eight A. Kish of the Pennsylvania Farm Bureau was teams competed. Chairman of the event, and J. F. Bauermann of Rutgers University was responsible for the local The members of the University of Maryland arrangements and facilities. team were Daniel W. Daly, James H. Comings and At the banquet, a gift certificate was presented Robert D. Noren. to Professor Luther Banta of the University of The individual winner was Robert Powers of Massachusetts in recognition of his forty years as a the University of Connecticut with 1080 points of a possible 1200. He received a prize of $35.00, coach of the University poultry judging teams. (Continued on page 394)
Downloaded from http://ps.oxfordjournals.org/ at Dalhousie University on June 20, 2015
approximately 60% of the total feed consumed contained vitamin A although it was presented to the birds only 50% of the time. Either the basal ration was unpalatable or some appetite stimulant was present in the vitamin additive which, expressed as growth, over-balanced the possible depressing effects of the basal ration during periods of its consumption. An examination of individual growth data indicated that there was no reason to suspect non-homogenous variance within lots which might have been caused by poor mixing. It may be concluded that the chemical vitamin A and the alfalfa meal materials added at the levels of approximately 11 and 227 grams per 100 pounds respectively, were distributed uniformly in all rations. If distribution of vtiamin A were questioned, the chemical material would more likely lack uniformity than the alfalfa meal.
389