The use of fiber concentrations for ration formulation.

摘要: Dairy cattle require fibrous feedstuffs in the diet. However, defining fiber requirements requires knowledge of many interacting components within diet as well how feed is allocated and processed. To meet demands high producing dairy cows for energy, diets consist large quantities concentrates quality forages containing relatively low amounts fiber. to maintain normal rumen function milk fat percentage, a portion needs come from forage. Current National Research Council recommendations are minimum 25 28% dietary neutral detergent fiber, 75% which supplied Chemical measures alone not adequate ration balancing; varies its effectiveness at stimulating chewing. This variation greater when feeds contain by-products place forages. The stimulation chewing variable particle size retention times indigestible digestible vary. Currently, little information exists about cow immediately postcalving until peak lactation. Early lactation clearly more limited by physical fill than mid late Rations based on nonforage sources (>45% dry matter basis) being evaluated early cows. Information needed determine amount fermentation acids produced, activity, saliva secreted these all contribute