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Comparative Value of Corn Distillers Dried Grains with Solubles, Soybean Oil Meal, and Linseed Oil Meal for Milk Production
C O M P A R A T I V E V A L U E OF CORN D I S T I L L E R S
DRIED GRAINS
WITH SOLUBLES, SOYBEAN OIL MEAL, AND LINSEED OID MEAL FOR MILK PRODUCTION J. K. LOOSLI, J. M. E L L I O T , 1 .~.~n R. G. W A R N E R D e p a r t m e n t of Animal H u s b a n d r y , Corne]l University, Ithaca, New York
SUGARY
Two experiments were conducted to compare the value for milk production of corn distillers dried grains with solubles, solvent extracted soybean oil meal, and linseed oil meal when these feeds were the primary protein supplements in milking rations. Milk production was significantly higher on the feeds containing corn distillers dried grains or soybean oil meal than on mixtures containing linseed oil meal. The digestibility of the three high protein supplements was measured with lactating cows. The supplements were fed as the only concentrate, along with second cutting alfalfa hay and the digestion coefficients calculated by difference. The total digestible nutrient values on a dry matter basis were 84.8, 85.2, and 67.8% for the corn distillers dried grains with solubles, soybean oil meal, and linseed oil meal, respectively. These experiments were u n d e r t a k e n because there were no recently published reports comparing corn distillers dried grains with solubles, solvent extracted soybean oil meal, and linseed oil meal as the main protein supplement for milk production, although these feeds are commonly used as protein sources in dairy rations. EXPERI~ENTAL PROCEDURE
Two experiments were carried out during the winters of 1957-58 and 1958-59. I n the first study, 15 p u r e b r e d Holstein cows which had recently passed their m a x i m u m daily milk yields were selected and grouped according to age and level of production into five replicates of three cows each. Two of the replicates involved cows 6 to 8 yr. of age and the others were in their first lactations. Five replicates of a 3 X 3 Latin-square design were used with 6-wk. experimental periods. F o r the second experiment a f o u r t h concentrate mixture was also fed, in which old process linseed oil meal served as the protein supplement. F i v e replicates of a 4 X 4 Latin-square involving 20 Holstein cows were employed. E i g h t of the cows were in their first lactation and the others were 5 to 9 yr. of age. The experimental periods were of 5-wk. duration. I n both studies the cows were fed average quality mixed grass hay, corn silage, and the concentrate mixture at the rate of a p p r o x i m a t e l y 1 lb. for each 3.5 lb. of 4% fat-corrected milk ( F C M ) produced daily d u r i n g the preexperimental period. The concentrate allowance was decreased at a u n i f o r m predetermined rate for all cows during the experiment. Records were kept of all feed consumed and of the milk produced. F a t percentage of the milk was determined on aliquot composite samples of four milkings Received for publication January 18, 1960. 1 Present address : Dairy and Animal Science Dept., University of Massachusetts, Amherst, Massachusetts. 816
CORN, SOYBEAN, AND FLAX PRODUCTS FOR PRODUCTION
817
each week. The cows were weighed on three days at the beginning of the experiment and at the end of each experimental period. The digestibilities of the protein supplements were determined in connection with E x p e r i m e n t I, using cows in late lactation. D u r i n g the digestion trials the supplements were fed at the rate of 8-16 lb. daily with 14-20 lb. of second cutting alfalfa hay. I t was found necessary to mix the linseed oil meal with corn distillers dried grains to induce the cows to consume it. Milk and F C M production and fat test data were analyzed by analysis of variance and D u n c a n ' s multiple range test as outlined by F e d e r e r (2). RESULTS AND DISCUSSION
The ingredients used in the concentrate mixtures and the of all of the feeds are shown in Tables I and 2, respectively. tion and body weight data are summarized in Table 3. I n both trials, the cows produced more milk and more trates containing corn distillers dried grains with solubles
chemical composition Milk and f a t producF C M on the concenor soybean oil meal,
TABLE 1 Ingredients used in the concentrate mixtures Mixture
Ingredient
A
B
C (lb.)
Corn distillers dried grains with solubles Soybean oil meal, solvent Linseed oil meal, old process Linseed oil meal, solvent Y e l l o w corn, g r o u n d
Oats, ground Wheat bran Cane molasses Diacaleium phosphate Salt Total" One g r a m
400 ......
-
-
.................. 210 ......
. . . . . . . . . . . .
......
300 210
400
310
200
200
200
100 70 10 10
100 70 10
100 70 10 10
1,000'
10 1,000
D
1,000
300 310
200 100 70 10
10 1,000
of cobalt sulfate was added to each 1,000 lb.
t h a n on the mixtures containing linseed oil meal. While none of the differences in production was statistically significant in E x p e r i m e n t I, the cows produced significantly ( P < 0.05) move F C M on corn distillers dried grains t h a n on linseed oil meal in E x p e r i m e n t I I . Old process and solvent p r o c e ~ linseed oil meal were of essentially equal value for F C M production. This is in agreement with the earlier observations of P r a t t and Monroe (4). The f a t test of the milk was significantly lower for the solvent process meal. Body weight gains in both experiments were variable and are diffficult to evaluate. I t should be no~ed, however, that they were somewhat higher on the average with the linseed oil meal supplements t h a n with either the distillers grains or soybean oil meal. A p p a r e n t digestion coefficients a n d T D N values for the three supplements used in E x p e r i m e n t I are presented in Table 4. W i t h the exception of the coefficient for ether extract, the values (including T D N ) obtained for soybean oil meal are in general agreement with those for cattle, as tabulated by Schneider (5).
818
J. K. LOOSLI, J. ~I. ELLIOT, AND R. G. WARNER
The v a l u e s o t h e r t h a n those f o r e t h e r e x t r a c t a n d c r u d e fiber are also in good agreement with those of Morrison
(3).
While neither Schneider nor Morrison
have listed digestion coefficients (for cattle) for corn distillers dried grains with TABLE 2 Chemical composition of the feeds Feed
Hay* Corn silage Corn distillers dried grains with solub]es Soybean oil meal, solvent Linseed off meal, solvent Concentrate containing : Corn distillers dried grains with solubles Soybean oil meal, solvent Linseed oil meal, solvent Hay b Corn silage Concentrate containing : Corn distillers dried grains with solubles Soybean oil meal, solvent Linseed oil meal, solvent Linseed oil meal, old process
Moisture
Protein
Fat
NFE
Ash
10.8 77.6
(%) Experiment I, 1957-58 10.6 1.8 34.2 1.8 0.6 6.7
Fiber
36.8 12.4
5.8 0.9
11.7 12.3 12.3
25.4 46.2 33.2
8.7 0.6 1.0
41.3 29.9 37.2
4.4 5.3 5.6
11.8 14.3
16.6 16.7 17.3
5.4 2.3
52.4 54.9 51.6
4.7 4.3 4.8
38.2 12.7
5.6 0.9
53.1 56.6 54.7 52.7
5.3 4.8 5.4 5.2
8.5 5.7 10.7
9.1 7.5 2.0 8.6 Experiment II, 1958-59 9.1 1.6 33.2 1.8 0.6 5.4
15.7 12.3 78.6 10.5 11.6 11.1 12.0
17.5 17.4 17.9 18.2
5.9 2.4 2.8 3.9
7.7 7.2 8.1 8.0
" U. S. G~o. 3 mixed hay. Color 35%. Factor analysis: Misc. grasses 45.6% (bhmgrass, red top, brome grass, cheat), timothy 42.5%, alfalfa 11.2%, clover 0.7%, and foreign material 16.9%. big. S. No. 2 mixed hay. Color 43%. Factor analysis: Timothy 44.1%, Misc. grasses 46.4% (blue grass, red top, brome grass, cheat), alfalfa 8.2%, clover 1.3%, and foreign material 6.3%. TABLE 3 Yields of milk and fat and the body ~veights of the cows Average daily Concentrate containing
Milk
Fat
(~b.)
(%)
Corn distillers dried grains with solubles Soybean oil meal, solvent process Linseed oil meal, solvent process
40.0 39.6 38.0
Corn distillers dried grains with solubles Soybean oil meal, solvent process Linseed oil meal, solvent process Linseed il meal, old process
42.4 42.1 40.2 39.7
Fat
FCM
Weight Body gain weight
(~b.)
Experiment I, 1957-58 3.71 1.45 37.8 0.86 3.77 1.47 38.0 0.40 3.79 1.43 36.7 0.95 Experiment II, 1958-59 3.83" 1.63 41.4 a 0.22 3.75" ' b 1.58 40.5"' b 0.37 3.72 ~ 1.50 38.5b 0.83 3.82" 1.52 38.6 b 0.73
1,146 1,149 1,158 1,255 1,250 1,245 1,248
, ~ b ( p ~ 0.05) Means within a single column with a common letter in the superscript are not significantly different; those without a common letter are different. s o l u b l e s , t h e T D N v a l u e o b t a i n e d i n t h i s s t u d y is s o m e w h a t l o w e r t h a n t h a t o f M o r r i s o z l , e v e n a f t e r t h e -ealues a r e c o r r e c t e d t o t h e s a m e m o i s t u r e b a s i s . T h e T D N v a l u e o f l i n s e e d oil m e a l a g r e e s q u i t e w e l l w i t h t h a t f o r S c h n c i d e r ' s
l i n s e e d oil
CORN, SOYBEAN, AND FLAX PRODUCTS FOR PRODUCTION
819
meal, 34% protein, but is considerably lower than the value for solvent process linseed meal as tabulated by Morrison. Apparent digestion coefficients for ether TABLE 4 Digestion coefficients and TDN values of the supplements Digestion coefficients
Nutrient Dry matter ( % ) Crude protein (% ) Ether extract (9'o) Nitregen-free extract ( % ) Orude fiber ( % ) Total digestible nutrients As fed (5*0) Dry basis ( % )
Corn distillers dried grains with solubles 77.0" (1.0)
Soybean oil meal, solvent
Linseed oil meal, solvent
91.8 (1.6) 79.5 (1.4) 48.9 (3.6)
89.5 (2.2) 92.4 (1.4) 78.4 (17.6) 93.7 (1.3) 51.4 (2.5)
67.9 (3.9) 83.1 (1.4) 73.9 (19.2) 73.9 (3.5) 25.2 (11.8)
74.9 (1.0) 84.8 (1.1)
74.7 (1.7) 85.2 (2.0)
59.4 (3.3) 67.8 (3.8)
78.7 (1.5)
"Mean of four values with the standard error of the mean in parentheses.
extract and crude fiber varied considerably among cows as is evident from the standard errors. This is to be expected in digestion trials where the feeds under test contain small quantities of these components. Average daily feed intakes of the cows during the lactation trials are summarized in Table 5. An attempt was made to keep feed intakes the same on the various TABLE 5 Average daily feed intakes Mixture containing
Concentrate
Hay
Silage
(ab.) Experiment I, 1957-58 Corn distillers dried grains with solubles 16.1 Soybean oil meal, solvent process 16.1 Linseed oil meal, solvent process 15.9 Experiment II, 1958-59 Corn distillers dried grains with solubles 15.4 Soybean oil meal, solvent process 15.3 Linseed oil meal, solvent process 15.0 Linseed oil meal, old process 14.9
14.4 14.3 14.6
28.5 29.0 30.4
12.8 13.9 14.4 14.3
39.0 39.8 40.6 40.3
rations. This objective was closely approached in both trials. The small differences in feed intake appear in themselves to be insufficient to explain the differences in milk yield. The protein supplements, however, differed in their TDN values. Thus, when the total daily TDN intakes are calculated (using tabulated values lot the ration ingredients other than the supplements), the results differ somewhat more among rations. This appears to explain, in large part, the production differences in Trial I. In Trial II, however, it still does not provide a full explanation. It is of interest in this connection that in both trials the ration producing the most F C M resulted in the smallest average body weight gain, and vice versa. This suggests that more o~ the energy in the rations containing linseed oil meal was diverted to body gain. No satisfactory explanation of this is available at the present time, although it has long been observed that linseed oil meal imparts a
~20
J. K. L O O S L I , J.
M. ELLIOT, AND R. G. XVARNER
certain bloom to cattle (1). It is apparent from the present studies, however, that linseed oil meal has a lower value for milk production than either soybean oil meal or corn distillers dried grains with solubles, when used as the chief protein source in the concentrate. This appears to be due primarily to its lower digestibility and, hence, energy value. ACKNOWLEDGMENT These studies were supported in p a r t by a research grant from the Distillers Feed Research Council, Cincinnati, Ohio, who also furnished the distillers feeds through the courtesy of Dr. L. E. Carpenter. REFERENCES (1) DIs~a% G. M., ItAYWA~, J. W., AN]) WITZ, W. M. Linseed Oil Meal. Feeding Practices and Research--Past, Present and Future. Feedstuffs, 31: 40. 1959. (2) F ~ , W A L ~ T, Experimental Design. Macmillan Company, New York. 1955. (3) MORP~SON, FIniNg B. Feeds and Feeding. 22nd ed. Morrison Publ. Co., Ithaca, New York. 1957. (4) P m ~ , A. D., AND MONm)S, C. F. Expeller vs. Solvent Process Linseed Oil Meal for Milking Cows. Ohio Agr. Expt. Sta., Research Bull. 731. 1953. (5) SCHI~rgn)E~, BURC~ HARW. Feeds of the World. West Virginia Agr. Expt. Sta., Morgantown. 1947.
DRIED GRAINS
WITH SOLUBLES, SOYBEAN OIL MEAL, AND LINSEED OID MEAL FOR MILK PRODUCTION J. K. LOOSLI, J. M. E L L I O T , 1 .~.~n R. G. W A R N E R D e p a r t m e n t of Animal H u s b a n d r y , Corne]l University, Ithaca, New York
SUGARY
Two experiments were conducted to compare the value for milk production of corn distillers dried grains with solubles, solvent extracted soybean oil meal, and linseed oil meal when these feeds were the primary protein supplements in milking rations. Milk production was significantly higher on the feeds containing corn distillers dried grains or soybean oil meal than on mixtures containing linseed oil meal. The digestibility of the three high protein supplements was measured with lactating cows. The supplements were fed as the only concentrate, along with second cutting alfalfa hay and the digestion coefficients calculated by difference. The total digestible nutrient values on a dry matter basis were 84.8, 85.2, and 67.8% for the corn distillers dried grains with solubles, soybean oil meal, and linseed oil meal, respectively. These experiments were u n d e r t a k e n because there were no recently published reports comparing corn distillers dried grains with solubles, solvent extracted soybean oil meal, and linseed oil meal as the main protein supplement for milk production, although these feeds are commonly used as protein sources in dairy rations. EXPERI~ENTAL PROCEDURE
Two experiments were carried out during the winters of 1957-58 and 1958-59. I n the first study, 15 p u r e b r e d Holstein cows which had recently passed their m a x i m u m daily milk yields were selected and grouped according to age and level of production into five replicates of three cows each. Two of the replicates involved cows 6 to 8 yr. of age and the others were in their first lactations. Five replicates of a 3 X 3 Latin-square design were used with 6-wk. experimental periods. F o r the second experiment a f o u r t h concentrate mixture was also fed, in which old process linseed oil meal served as the protein supplement. F i v e replicates of a 4 X 4 Latin-square involving 20 Holstein cows were employed. E i g h t of the cows were in their first lactation and the others were 5 to 9 yr. of age. The experimental periods were of 5-wk. duration. I n both studies the cows were fed average quality mixed grass hay, corn silage, and the concentrate mixture at the rate of a p p r o x i m a t e l y 1 lb. for each 3.5 lb. of 4% fat-corrected milk ( F C M ) produced daily d u r i n g the preexperimental period. The concentrate allowance was decreased at a u n i f o r m predetermined rate for all cows during the experiment. Records were kept of all feed consumed and of the milk produced. F a t percentage of the milk was determined on aliquot composite samples of four milkings Received for publication January 18, 1960. 1 Present address : Dairy and Animal Science Dept., University of Massachusetts, Amherst, Massachusetts. 816
CORN, SOYBEAN, AND FLAX PRODUCTS FOR PRODUCTION
817
each week. The cows were weighed on three days at the beginning of the experiment and at the end of each experimental period. The digestibilities of the protein supplements were determined in connection with E x p e r i m e n t I, using cows in late lactation. D u r i n g the digestion trials the supplements were fed at the rate of 8-16 lb. daily with 14-20 lb. of second cutting alfalfa hay. I t was found necessary to mix the linseed oil meal with corn distillers dried grains to induce the cows to consume it. Milk and F C M production and fat test data were analyzed by analysis of variance and D u n c a n ' s multiple range test as outlined by F e d e r e r (2). RESULTS AND DISCUSSION
The ingredients used in the concentrate mixtures and the of all of the feeds are shown in Tables I and 2, respectively. tion and body weight data are summarized in Table 3. I n both trials, the cows produced more milk and more trates containing corn distillers dried grains with solubles
chemical composition Milk and f a t producF C M on the concenor soybean oil meal,
TABLE 1 Ingredients used in the concentrate mixtures Mixture
Ingredient
A
B
C (lb.)
Corn distillers dried grains with solubles Soybean oil meal, solvent Linseed oil meal, old process Linseed oil meal, solvent Y e l l o w corn, g r o u n d
Oats, ground Wheat bran Cane molasses Diacaleium phosphate Salt Total" One g r a m
400 ......
-
-
.................. 210 ......
. . . . . . . . . . . .
......
300 210
400
310
200
200
200
100 70 10 10
100 70 10
100 70 10 10
1,000'
10 1,000
D
1,000
300 310
200 100 70 10
10 1,000
of cobalt sulfate was added to each 1,000 lb.
t h a n on the mixtures containing linseed oil meal. While none of the differences in production was statistically significant in E x p e r i m e n t I, the cows produced significantly ( P < 0.05) move F C M on corn distillers dried grains t h a n on linseed oil meal in E x p e r i m e n t I I . Old process and solvent p r o c e ~ linseed oil meal were of essentially equal value for F C M production. This is in agreement with the earlier observations of P r a t t and Monroe (4). The f a t test of the milk was significantly lower for the solvent process meal. Body weight gains in both experiments were variable and are diffficult to evaluate. I t should be no~ed, however, that they were somewhat higher on the average with the linseed oil meal supplements t h a n with either the distillers grains or soybean oil meal. A p p a r e n t digestion coefficients a n d T D N values for the three supplements used in E x p e r i m e n t I are presented in Table 4. W i t h the exception of the coefficient for ether extract, the values (including T D N ) obtained for soybean oil meal are in general agreement with those for cattle, as tabulated by Schneider (5).
818
J. K. LOOSLI, J. ~I. ELLIOT, AND R. G. WARNER
The v a l u e s o t h e r t h a n those f o r e t h e r e x t r a c t a n d c r u d e fiber are also in good agreement with those of Morrison
(3).
While neither Schneider nor Morrison
have listed digestion coefficients (for cattle) for corn distillers dried grains with TABLE 2 Chemical composition of the feeds Feed
Hay* Corn silage Corn distillers dried grains with solub]es Soybean oil meal, solvent Linseed off meal, solvent Concentrate containing : Corn distillers dried grains with solubles Soybean oil meal, solvent Linseed oil meal, solvent Hay b Corn silage Concentrate containing : Corn distillers dried grains with solubles Soybean oil meal, solvent Linseed oil meal, solvent Linseed oil meal, old process
Moisture
Protein
Fat
NFE
Ash
10.8 77.6
(%) Experiment I, 1957-58 10.6 1.8 34.2 1.8 0.6 6.7
Fiber
36.8 12.4
5.8 0.9
11.7 12.3 12.3
25.4 46.2 33.2
8.7 0.6 1.0
41.3 29.9 37.2
4.4 5.3 5.6
11.8 14.3
16.6 16.7 17.3
5.4 2.3
52.4 54.9 51.6
4.7 4.3 4.8
38.2 12.7
5.6 0.9
53.1 56.6 54.7 52.7
5.3 4.8 5.4 5.2
8.5 5.7 10.7
9.1 7.5 2.0 8.6 Experiment II, 1958-59 9.1 1.6 33.2 1.8 0.6 5.4
15.7 12.3 78.6 10.5 11.6 11.1 12.0
17.5 17.4 17.9 18.2
5.9 2.4 2.8 3.9
7.7 7.2 8.1 8.0
" U. S. G~o. 3 mixed hay. Color 35%. Factor analysis: Misc. grasses 45.6% (bhmgrass, red top, brome grass, cheat), timothy 42.5%, alfalfa 11.2%, clover 0.7%, and foreign material 16.9%. big. S. No. 2 mixed hay. Color 43%. Factor analysis: Timothy 44.1%, Misc. grasses 46.4% (blue grass, red top, brome grass, cheat), alfalfa 8.2%, clover 1.3%, and foreign material 6.3%. TABLE 3 Yields of milk and fat and the body ~veights of the cows Average daily Concentrate containing
Milk
Fat
(~b.)
(%)
Corn distillers dried grains with solubles Soybean oil meal, solvent process Linseed oil meal, solvent process
40.0 39.6 38.0
Corn distillers dried grains with solubles Soybean oil meal, solvent process Linseed oil meal, solvent process Linseed il meal, old process
42.4 42.1 40.2 39.7
Fat
FCM
Weight Body gain weight
(~b.)
Experiment I, 1957-58 3.71 1.45 37.8 0.86 3.77 1.47 38.0 0.40 3.79 1.43 36.7 0.95 Experiment II, 1958-59 3.83" 1.63 41.4 a 0.22 3.75" ' b 1.58 40.5"' b 0.37 3.72 ~ 1.50 38.5b 0.83 3.82" 1.52 38.6 b 0.73
1,146 1,149 1,158 1,255 1,250 1,245 1,248
, ~ b ( p ~ 0.05) Means within a single column with a common letter in the superscript are not significantly different; those without a common letter are different. s o l u b l e s , t h e T D N v a l u e o b t a i n e d i n t h i s s t u d y is s o m e w h a t l o w e r t h a n t h a t o f M o r r i s o z l , e v e n a f t e r t h e -ealues a r e c o r r e c t e d t o t h e s a m e m o i s t u r e b a s i s . T h e T D N v a l u e o f l i n s e e d oil m e a l a g r e e s q u i t e w e l l w i t h t h a t f o r S c h n c i d e r ' s
l i n s e e d oil
CORN, SOYBEAN, AND FLAX PRODUCTS FOR PRODUCTION
819
meal, 34% protein, but is considerably lower than the value for solvent process linseed meal as tabulated by Morrison. Apparent digestion coefficients for ether TABLE 4 Digestion coefficients and TDN values of the supplements Digestion coefficients
Nutrient Dry matter ( % ) Crude protein (% ) Ether extract (9'o) Nitregen-free extract ( % ) Orude fiber ( % ) Total digestible nutrients As fed (5*0) Dry basis ( % )
Corn distillers dried grains with solubles 77.0" (1.0)
Soybean oil meal, solvent
Linseed oil meal, solvent
91.8 (1.6) 79.5 (1.4) 48.9 (3.6)
89.5 (2.2) 92.4 (1.4) 78.4 (17.6) 93.7 (1.3) 51.4 (2.5)
67.9 (3.9) 83.1 (1.4) 73.9 (19.2) 73.9 (3.5) 25.2 (11.8)
74.9 (1.0) 84.8 (1.1)
74.7 (1.7) 85.2 (2.0)
59.4 (3.3) 67.8 (3.8)
78.7 (1.5)
"Mean of four values with the standard error of the mean in parentheses.
extract and crude fiber varied considerably among cows as is evident from the standard errors. This is to be expected in digestion trials where the feeds under test contain small quantities of these components. Average daily feed intakes of the cows during the lactation trials are summarized in Table 5. An attempt was made to keep feed intakes the same on the various TABLE 5 Average daily feed intakes Mixture containing
Concentrate
Hay
Silage
(ab.) Experiment I, 1957-58 Corn distillers dried grains with solubles 16.1 Soybean oil meal, solvent process 16.1 Linseed oil meal, solvent process 15.9 Experiment II, 1958-59 Corn distillers dried grains with solubles 15.4 Soybean oil meal, solvent process 15.3 Linseed oil meal, solvent process 15.0 Linseed oil meal, old process 14.9
14.4 14.3 14.6
28.5 29.0 30.4
12.8 13.9 14.4 14.3
39.0 39.8 40.6 40.3
rations. This objective was closely approached in both trials. The small differences in feed intake appear in themselves to be insufficient to explain the differences in milk yield. The protein supplements, however, differed in their TDN values. Thus, when the total daily TDN intakes are calculated (using tabulated values lot the ration ingredients other than the supplements), the results differ somewhat more among rations. This appears to explain, in large part, the production differences in Trial I. In Trial II, however, it still does not provide a full explanation. It is of interest in this connection that in both trials the ration producing the most F C M resulted in the smallest average body weight gain, and vice versa. This suggests that more o~ the energy in the rations containing linseed oil meal was diverted to body gain. No satisfactory explanation of this is available at the present time, although it has long been observed that linseed oil meal imparts a
~20
J. K. L O O S L I , J.
M. ELLIOT, AND R. G. XVARNER
certain bloom to cattle (1). It is apparent from the present studies, however, that linseed oil meal has a lower value for milk production than either soybean oil meal or corn distillers dried grains with solubles, when used as the chief protein source in the concentrate. This appears to be due primarily to its lower digestibility and, hence, energy value. ACKNOWLEDGMENT These studies were supported in p a r t by a research grant from the Distillers Feed Research Council, Cincinnati, Ohio, who also furnished the distillers feeds through the courtesy of Dr. L. E. Carpenter. REFERENCES (1) DIs~a% G. M., ItAYWA~, J. W., AN]) WITZ, W. M. Linseed Oil Meal. Feeding Practices and Research--Past, Present and Future. Feedstuffs, 31: 40. 1959. (2) F ~ , W A L ~ T, Experimental Design. Macmillan Company, New York. 1955. (3) MORP~SON, FIniNg B. Feeds and Feeding. 22nd ed. Morrison Publ. Co., Ithaca, New York. 1957. (4) P m ~ , A. D., AND MONm)S, C. F. Expeller vs. Solvent Process Linseed Oil Meal for Milking Cows. Ohio Agr. Expt. Sta., Research Bull. 731. 1953. (5) SCHI~rgn)E~, BURC~ HARW. Feeds of the World. West Virginia Agr. Expt. Sta., Morgantown. 1947.