Khorasani G R, de Boer G, Robinson B, Kennelly J J
Department of Animal Science University of Alberta, Edmonton, Canada.
J Dairy Sci. 1994 Mar;77(3):813-24. doi: 10.3168/jds.S0022-0302(94)77016-8.
The effects of starch and CP degradability on ruminal digestion, milk yield, and milk composition were evaluated using a 4 x 4 Latin square design. Thirty-six Holstein cows (15 multiparous; 21 primiparous) and 4 ruminally cannulated cows were assigned randomly to four diets. The experiment was conducted during wk 4 through 16 postpartum. Diets contained 60% concentrate and 40% bromegrass hay. Treatments were barley plus canola meal and soybean meal; barley plus corn gluten meal, fish meal, and meat and bone meal; corn plus canola meal and soybean meal; and corn plus corn gluten meal, fish meal, and meat and bone meal. Intake of DM was not influenced by starch source, but CP intake was higher for diets based on corn than for those based on barley. Yields of milk, milk protein, and lactose were higher for diets based on fish meal than canola meal but were not altered by dietary starch source. Milk protein percentage and 4% FCM yield were not altered by dietary protein source. The 4% FCM and milk fat yields were higher for cows fed diets based on corn than for cows fed diets based on barley. Cows fed diets based on corn had significantly lower concentrations of most short- and medium-chain fatty acids and elevated concentrations of C18:0, C18:1, and C18:2 in milk. Protein source significantly influenced milk yield, and milk composition was altered by starch source. However, no interaction was observed between starch and protein sources.
采用4×4拉丁方设计，评估淀粉和粗蛋白降解率对瘤胃消化、产奶量及乳成分的影响。36头荷斯坦奶牛（15头经产牛；21头初产牛）和4头安装了瘤胃瘘管的奶牛被随机分配到四种日粮。试验在产后第4至16周进行。日粮包含60%精料和40%雀麦干草。处理组分别为大麦加油菜籽粕和豆粕；大麦加玉米蛋白粉、鱼粉和肉骨粉；玉米加油菜籽粕和豆粕；以及玉米加玉米蛋白粉、鱼粉和肉骨粉。干物质摄入量不受淀粉来源的影响，但以玉米为基础的日粮粗蛋白摄入量高于以大麦为基础的日粮。以鱼粉为基础的日粮产奶量、乳蛋白产量和乳糖产量高于以油菜籽粕为基础的日粮，但不受日粮淀粉来源的影响。乳蛋白率和4%乳脂校正乳产量不受日粮蛋白质来源的影响。以玉米为基础的日粮喂养的奶牛4%乳脂校正乳和乳脂产量高于以大麦为基础的日粮喂养的奶牛。以玉米为基础的日粮喂养的奶牛乳中大多数短链和中链脂肪酸浓度显著较低，而C18:0、C18:1和C18:2浓度升高。蛋白质来源显著影响产奶量，淀粉来源改变乳成分。然而，未观察到淀粉和蛋白质来源之间的交互作用。
