Effects of Postrumen Starch Infusion on Milk Production and Energy Metabolism in Dairy Cows

摘要

Two experiments were conducted to determine effects of postrumen starch infusion on milk production and energy and nitrogen utilization in lactating dairy cows. In experiment 1, four cows in early lactation fed grass Silage and concentrates were continuously infused into The duodenum with water or 700, 1400, or 2100 g of Purified maize starch daily for 10 to 12 d in a 4 ×4 Latin square design with 2 - wk periods. Starch infusion Increased milk yield linearly and decreased milk fat Concentration in a quadratic manner such that in - Creases in fat - corrected milk and calculated milk energy Yield were minimal except at the highest rate of infu - Sion.