Lactational performance and nutrient utilization in high producing cows fed sorghum grains of varying starch degradabilities with or without fat supplementation

摘要: 7 Twenty four multiparous and twelve primiparous Holstein cows were assigned at calving to treatments in a 2X2 factorial design. Factors were: 1) grain processing:dry rolled sorghum (D) vs. steam flaked (S) ; 2) rumen inert fat: supplemented (F) non (C). The F diets 2.5% of dry matter (DM) as Casoaps. S increased (Pc.02) milk production 12%, while decreased (Pc.28) 5%, due 16% decrease (P<.01) feed intake. However, efficiency utilization 15%, partially sustained by greater (P<.08) body weight losses. DF diet protein 0.21% compared the DC diet, but had similar content regardless fat supplementation. Milk yields higher for diets. (P<.03) percentages not affected. digestibilities DM, CP, GE, starch than D Digestibilities CP GE (P<.05) C Steam maintained percent lactation with Ca-Soaps fatty acids.