Feeding lactating dairy cows proteins resistant to ruminal degradation
1988
Voss, V.L. | Stehr, D. | Satter, L.D. | Broderick, G.A.
Sixty multiprious Holstein cows were fed treatment diets from 11 to 40 d post-partum with corn silage as the forage. Treatment diets each contained a different supplemental protein: 1) solvent soybean meal; 2) extruded soy product; 3) combination of corn gluten meal and distillers dried grains with solubles; and 4) a combination of protein sources from diets 2 and 3. Covariate adjusted means for milk (kg/d) and milk fat (%) for treatments 1 through 4 were 37.5, 3.14, 38.5, 3.19; 31.8, 3.45; and 35.2, 3.08. Milk protein content and DM intake were greatest for cows fed diet 1. In a second trial, 105 multiparous Holstein cows 13 d postpartum were placed on 7 treatment diets for 60 d. Treatments 1 to 5 contained equal amounts of corn silage and alfalfa silage as forage sources and contained either: 1) solvent soybean meal; 2) roasted soybean meal; 3) roasted soybeans; 4) roasted soybeans and urea; or 5) a mixture of corn distillers dried grains and corn gluten meal. Treatments 6 and 7 had alfalfa silage as the forage source and either 6) solvent soybean meal or 7) roasted soybeans as the supplemental protein. Feeding roasted soybeans with the alfalfa silage based diets increased milk 2.0 kg/d 4% FCM 4.6 kg/d,adn fat .23 kg/d when compared with solvent soybean meal. Milk production was depressed by feeding a combination of distillers dried grains and corn gluten meal when compared with feeding diets containing soybean sources with the corn silage-alfalfa silage diets. Resistant protein sources may have greater value with diets containing alfalfa silage than with diets containing corn silage.
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