芽孢杆菌制剂对艾维茵肉鸡胴体性能和肠道菌群的影响

试验选用7日龄艾维茵肉仔鸡480只,随机分为8组,每组3个重复,每个重复20只;选择适宜肉鸡饲喂的3种芽孢杆菌制剂,分别为枯草芽孢杆菌BS3(Bacillus subtilis 3)、产蛋白酶活力高的蜡样芽孢杆菌BC1(Bacillus cereus 1)和产纤维素酶活力高的蜡样芽孢杆菌BC2(B.cereus 2),将其单一或复合的添加到肉鸡日粮中,研究芽孢杆菌制剂对肉鸡胴体性能、免疫器官指数及肠道菌群的影响;8个试验组分别为对照组和BC1、BC2、BS3单一供给组及BC1+BC2、BC1+BS3、BC2+BS3、BC1+BC2+BS3 4个混合供给组,饲料中芽孢杆菌的添加量为3×105 CFU.g-1,混合组的配比为1∶1和1∶1∶1。结果表明:与对照组相比,添加BC1+BC2对提高肉鸡日增质量和降低料质量比效果显著(P<0.05),其中日增质量提高了9.97%,料质量比降低了8.46%;添加BC1和BC1+BC2组肉鸡的腿肌率分别提高了8.46%和7.95%(P<0.05),BC1、BC1+BC2和BC1+BC2+BS3组的腹脂率较对照组显著降低,分别降低了26.6%、30.2%和25.8%;日粮中添加BC1+BC2和BC1+BC2+BS3显著提高了脾脏指数(P<0.05),添加BC1+BC2、BC1+BS3和BC1+BC2+BS3组的法氏囊指数显著提高,添加BC1+BC2、BC1+BS3和BC1+BC2+BS3显著降低了肉鸡盲肠道内的大肠杆菌数(P<0.05)。本试验结果表明适用肉鸡的最佳芽孢杆菌制剂是BC1+BC2。

Effects of Bacillus preparation on carcass performance and intestinal microflora of Avian broiler chicken

A total of 480 7-day-old Avian broilers were randomly divided into eight groups with three replicates per group and twenty birds in each replicate(half male and half female).Single or multiple ones of three kinds of Bacillus preparation suitable for the birds were added to the daily diet of chicken to investigate the effects of Bacillus additive on the growth performance,carcass,immunity and intestinal microflora of broilers.The eight groups were the control group,BC1(B.cereus with high ability of producing protease),BC2(B.cereus with high ability of producing cellulase),BS3(B.subtilis) group and BC1+BC2,BC1+BS3,BC2+BS3,BC1+BC2+BS3 group,respectively,and the additive amount of every kind of Bacillus preparation in daily diet of treatment groups was 3×105 CFU·g-1.The results showed that the daily mass gain and the feed-to-gain ratio of broilers fed diet with BC1+BC2 were affected significantly,with the daily mass gain increasing by 9.97% and the feed-to-gain ratio decreasing by 8.46%;the leg muscle rate of broiler in BC1 and BC1+BC2 groups was increased significantly by 8.46% and 7.95% respectively,compared with the control group;the abdominal fat rate in BC1,BC1+BC2 and BC1+BC2+BS3 groups was decreased significantly by 26.6%,30.2% and 25.8% respectively,and the spleen index of broiler in BC1+BC2 and BC1+BC2+BS3 groups was improved significantly,as well as the bursa index in BC1+BC2,BC1+BS3 and BC1+BC2+BS3 groups,compared with the control group.Adding BC1+BC2,BC1+BS3 and BC1+BC2+BS3 in daily diet could reduce significantly the number of Escherichia coli in broiler caecum.These results above indicate that the optimal Bacillus preparation for broiler is BC1+BC2.