Effect of Boulardii Yeast Wall Polysaccharides on Intestinal Microflora in Jejunum, Cecum and Colon for Early-Weaned Lambs by 16S rRNA Sequence Analysis

This study was conducted to investigate the effects of Boulardiiyeast wall polysaccharide (BRYP) on the intestinal micro-ecosystem of early-weaned lambs. A total of 60 early-weaned lambs (35-days-old, Kazak♂*Altay♀*Suffolk♂) were randomly assigned into two treatments: a control group with a basal diet, an experimental group with a basal diet and added 0.05% BRYP. The HiSeq high-throughput sequencing analysis of 16SrRNA was used to investigate the differences in intestinal microbial flora composition, diversity, relative abundance, principle coordination analysis, and the correlation between intestinal microbial flora composition and immune indices. After feeding for 40days, the addition of 0.5% BRYP in milk replacer significantly enhanced the species richness in the cecum and colon, but decreased the diversity of species in the colon (P <0.05); Compared with the control group, the relative abundance of Bacteroidetes in the experimental group was significantly enhanced, but the Proteobacteria was significantly decreased in all tested intestinal segments (P <0.05).In the jejunum, the relative abundance of Lactobacillus, Prevotella, and Fibrobacter of the experimental group were significantly enhanced than that of the control group, but the Ruminobacter was significantly decreased (P <0.05); In the cecum, the relative abundance of Bacteroides, Lactobacillus, Oscillospira and Bifidobacterium of the experimental group were significantly enhanced than that of the control group, but the Blautia were significantly decreased (P <0.05); In the colon, the relative abundance of Akkermansia, Bifidobacterium, Lactobacillus and Faecalibacteriumof the experimental group were significantly enhanced than that of the control group, but the Prevotella, Streptococcus, and Escherichia were significantly decreased (P <0.05). There were significant correlations between intestinal immune indices (IL-6, IL-10, TNF-α) and intestinal microbial composition in the colon (P <0.05). These results indicated that BRYP may contribute to the promotion of the proportion of helpful microbial populations and enhancing the balance of intestinal; Besides, BRYP may indirectly improve the intestinal immune function by changes of intestinal microflora composition, but suppress the inflammatory response in the bottom of intestinal mucosa of early-weaned lambs.© 2021 Friends Science Publishers