活性干酵母对不同粗饲料瘤胃降解的影响

Effects of active dried yeast on ruminal digestibility of different roughages

为研究活性干酵母对不同粗饲料瘤胃降解的影响,试验选用6头平均体重为[(457.80±18.15)kg]的安装有永久性瘤胃瘘管的宣汉黄牛,随机分为两个处理,每个处理3个重复,每个重复1头牛,酵母组在对照组日粮基础上添加0.1%的活性干酵母。采用瘤胃尼龙袋法评估活性干酵母对苜蓿颗粒、玉米青贮秸秆、黑麦干草和全混合日粮(TMR)的干物质(DM)、粗蛋白质(CP)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)在瘤胃6、12、24、36、48、72 h降解率的影响。试验预饲期10 d,正式期3 d。结果显示:(1)日粮中添加活性干酵母能够显著提高不同粗饲料(苜蓿颗粒、玉米青贮秸秆、黑麦干草)及TMR日粮NDF、ADF、DM、CP在肉牛瘤胃的快速发酵比例(P<0.05),有利于提高瘤胃降解速率;(2)活性干酵母可显著提高苜蓿颗粒、玉米青贮秸秆、黑麦干草及TMR日粮NDF、ADF、DM、CP在肉牛瘤胃中的72 h内有效降解率(P<0.05)。结果表明活性干酵母可以改善粗饲料的利用效率。

This study was conducted to determine the effects of active dried yeast on ruminal digestibility of different roughages.A total of six Xuanhan cattles[BW(457.80±18.15)kg]with permanent rumen fistula were divided into two treatments randomly.There were 3 replications in each group and 1 cattle per replication.The experimental cattle were fed with basic diet and cattle in yeast group were given 0.1%active dried yeast.The present trial was designed to test the effect of yeast on dry matter(DM),crude protein(CP),neutral detergent fiber(NDF)and acid detergent fiber(ADF)degradation of alfalfa particles,corn straw silage,rye hay and total mixed ration at 6,12,24,36,48,72 h by nylon bag technique.The adaptive period was 10 days and the experimental period lasted for 3 d.The results showed that:(1)The NDF,ADF,DM,CP rapid degraded fraction of alfalfa particles,corn straw silage,rye hay and total mixed ration in rumen were enhanced significantly by adding active dried yeast(P<0.05).(2)The yeast caused a significant increase of NDF,ADF,DM,CP effective degradation rate of different roughages within 72 h(P<0.05).In conclusion,active dry yeast could improve the utilization efficiency of roughage.