Ruminal microbiota and fermentation in response to the dietary energy level in weaned lambs

摘要

The rumen bacterial community plays a vital role in feed digestion and assimilation. This study aimed to evaluate ruminal microbiota and fermentation in response to different dietary energy levels in weaned lambs. Thirty-two two-months old Hu lambs were divided into two groups receiving diets differing in energy density (ME=10.92 MJ/kg or 8.64 MJ/kg). After 60 days, six lambs from each group were slaughtered, and samples of rumen contents and fluid were taken for 16s DNA and fermentation analysis. The ruminal acetate concentration and the ratio of acetate to propionate increased but the propionate concentration decreased significantly in lambs fed the low energy diet. Furthermore, low dietary energy sharply reduced the abundance of genus Succinivibrionaceae-uncultured (PO.05), which was associated with the change of ruminal fermentation phenotypes. These findings added new dimensions to our understanding of the diet effect on rumen microbial community and are of great significance for establishingthe optimal nutrient supply strategy for lambs.