摘要
两头带瘤胃瘘管的阉公牛饲喂三种不同口粮:日粮Ⅰ、Ⅲ的精粗比为1∶3,日粮Ⅱ的精粗比为1∶1;日粮Ⅰ、Ⅱ的蛋白质补充料为豆饼,日粮Ⅲ的蛋白质补充料则为菜籽饼。测定不同日粮,不同采样时间和不同瘤胃部位对瘤胃细菌的 RNA—N/细菌氮和 DAPA—N/细菌氮比值的影响。日粮Ⅰ、Ⅱ、Ⅲ的瘤胃细菌 RNA—N/细菌氮有明显的差异,比值分别为0.1395、0.0833、0.1155,相应变异系数为7.82％、12.18％、9.40％。同一日粮的不同采样时间和瘤胃不同采样部位的 RNA—N/细菌氮没有显著的差异。其变异系数日粮Ⅰ为7.36％和7.80％;日粮Ⅱ为9.05％和12.14％;日粮Ⅲ为9.26％和9.22％。日粮Ⅰ、Ⅱ、Ⅲ的瘤胃细菌 DAPA—N/细菌氮的比值分别为0.5375％、0.4005％,0.5067％,日粮之间有显著差异;相应变异系数为8.13％、10.42％、8.96％。同一日粮内不同采样时间和不同采样部位的 DAPA—N/细菌氮的值差异不显著,日粮Ⅰ、Ⅱ、Ⅲ的不同采样时间和不同采样部位的变异系数分别为7.52％、8.18％;11.37％、11.622％;8.38％、9.04％。
Two rumen—fistulated steers were fed with three types of diet,i.e.,diet Ⅰ,Ⅲ(75% hay and 25% concentrate)and diet Ⅱ(50% concentrate and 50%hay)to collect rumen contents for studying the effects of diets,time and rumen position of sampling on the ratio of RNA—N and DAPA—N to bacterial nitrogen(BN)of rumen bacteria. Bacteria from high roughage diet had higher more RNA-N/BN and DAPA—A/BN ratio than from the high concen- trate diets with significant differences between the three diets.Results showed that RNA—N/BN were 0.1395,0.0833, 0.1155,for diet Ⅰ,Ⅱ,Ⅲ,and DAPA—N/BN were 0.5357%,0.4005%,0.5067% respectively.Time and position in the rumen of sampling had no effect on RNA—N/BN and DAPA—N/BN,But their coefficients of variation from diet Ⅱ were higher than from diets Ⅰ and Ⅲ,The variation coeffcients(of RNA—N/BN)for time sampling and sampling position in the rumen with diet Ⅰ,Ⅱ,Ⅲ were 7.36%,7.80;9.05%,12.14%;9.62%,9.22%, and of DAPA—N/BN were 7.25%,8.1%;11.37%,11.62%;8.38%,9.04% respectively.
