日粮不同蛋白源对绵羊瘤胃发酵功能的影响

The effect of different dietary nitrogen sources on the ruminal fermentation of sheep

为了研究日粮中不同蛋白饲料来源对绵羊瘤胃发酵功能的影响。本试验选用12只体重50 kg左右的苏尼特绵羊,随机分为4组,每组3只,Ⅰ组、Ⅱ组、Ⅲ组、Ⅳ组分别饲喂氮源为葵粕+玉米蛋白粉、鱼粉、棉粕、豆粕的日粮。结果表明:Ⅲ组瘤胃pH显著高于Ⅳ组(P<0.05);瘤胃NH3-N浓度、总VFA和丁酸的浓度受氮源影响不显著(P>0.05),对乙酸、丙酸浓度和乙酸∶丙酸比例影响显著,Ⅱ组乙酸∶丙酸比例显著低于其它3组(P<0.05)。不同氮源日粮对固相食靡流通速率、纤维物质的动态降解率影响不显著(P>0.05),但Ⅲ组(棉粕)纤维物质降解率最高。表明日粮蛋白源的变化改变了瘤胃发酵模式。

12 Sunite sheep, healthy and weighting about 50 kg, were randomly divided into 4 groups. Nitrogen sources of the diets were sunflowerseed meal＋zein, fish meal, cottonseed meal and soybean meal for group Ⅰ,group Ⅱ,group Ⅲ and group Ⅳ respectively. The results indicated that Nitrogen sources significantly influenced rumen pH value, and pH of group Ⅲ was significantly higher than that of group Ⅳ （P〈0.05）. No significant differences were found between groups in the concentration of NH3 - N,total VFA and butyric acid （P〉0.05）. However,in terms of the concentration of acetic acid and acetic acid, the propionic acid for group Ⅱ was significantly lower than for other groups （P〈0.05）. The results also showed that there were no significant differences between groups in solid fractional passage rate and fiber dynamic deg- radation coefficients （P〉0.05）. In addition rumen fiber digestibility in group Ⅲ was higher than the other groups. The fermentation mode of rumen varied with the transformation of dietary nitrogen sources.