奶牛主要饲料原料蛋白质瘤胃降解率的研究

The Study on Protein Degradability of Main Feeds in Rumen of Dairy Cows

以3头安装永久性瘤胃瘘管的荷斯坦产奶牛为试验动物,用尼龙袋法研究测定了奶牛常用饲料蛋白质在瘤胃内的动态降解规律及其有效降解率。结果表明:常用蛋白质饲料中葵花粕与豆粕粗蛋白(CP)的有效降解率较高,酒糟CP降解率最低。籽实与糠麸类饲料中麸皮CP有效降解率最高,稻壳最低。常用粗饲料中苜蓿草与苜蓿草块的CP有效降解率均高于其他粗饲料,玉米秸秆的CP有效降解率最低。不同饲料蛋白质瘤胃有效降解率与蛋白质慢速降解组分呈极显著中度正相关(r=0.5013,P<0.01),与蛋白质快速降解组分呈弱的正相关(相关性趋于显著r=0.3675,P=0.06),与非降解组分呈极显著高度负相关(r=-0.7153,P<0.01)。

Three Holstein cows fitted permanent rumen fistula were selected to estimate the dynamic degradability and effective degradation rate of protein in rumen by nylon bag technique. The results show that the effective degradation rate of protein in sunflower meal and soy bean meal is higher among all protein feeds, and the effective degradation rate of protein is the lowest for lees meal. Among all kinds of grains and bran, the effective degradation rate of CP of wheat bran is the highest. it is the lowest for rice chaff. Among all roughages, the effective degradation rate of CP of alfalfa and alfalfa block is higher than other roughages, and the effective degradation rate of CP of corn straw is the lowest. There are weak positive correlation between the effective degradation rate of protein and rapid degraded part（r=0.3675, P=0.06）, and there are mid-strong positive correlation between the effective degradation rate of protein and slowly degraded part（r=0.5013 ,P〈0.01 ）, and there are strong negative correlation between the effective degradation rate of protein and undergraded part（r=-0.7153 ,P〈0.01 ）.