益生菌制剂对犊牛生长性能、免疫力及肠道菌群结构的影响OA

This experiment aimed to investigate the effects of probiotic preparation on the growth performance,immune function,and intestinal microflora structure in calves.A total of 60 healthy Simmental calves with similar body weight were randomly divided into four groups,with 15 replicates per group and one calf per replicate.The control group was fed a basal diet,while the experimental groups received the basal diet supplemented with 0.25%(0.25%probiotic group),0.50%(0.50%probiotic group),and 1.00%(1.00%probiotic group)probiotic preparation,respectively.The pre-test period was seven days,and the formal test period was 60 days.The results showed that compared with the control group,the weight gain and average daily gain in the 0.50%and 1.00%probiotic groups were significantly increased(P<0.05),and the diarrhea rate was significantly decreased(P<0.05).Serum levels of immunoglobulin G(IgG)and interleukin-2(IL-2)in experimental groups were significantly increased(P<0.05).The content of interleukin-10(IL-10)in the 0.50%and 1.00%probiotic groups was significantly elevated(P<0.05),while interleukin-6(IL-6)content was significantly reduced(P<0.05).The Chao1 index in experimental groups was significantly increased(P<0.05),and the Shannon index in the 0.50%probiotic group was significantly increased(P<0.05).The relative abundances of Bacteroidota,Proteobacteria and Bacteroides in the 0.50%probiotic group were significantly decreased(P<0.05),while Firmicutes was significantly increased(P<0.05).The study shows that probiotic preparation can improve growth performance,enhance immune function,and promote intestinal health in calves,with 0.50%supplementation level showing the most pronounced effects.