AUTHOR=An Yawen , Wang Hairong , Zong Zichao , Gao Zhixiong , Shi Caixia , Li Shufang , Khas-Erdene  

TITLE=Effects of adding Sophora alopecuroides to high concentrate diet on rumen fermentation parameters and microbial diversity of sheep

JOURNAL=Frontiers in Veterinary Science

VOLUME=10

YEAR=2023

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2023.1200272

DOI=10.3389/fvets.2023.1200272

ISSN=2297-1769

ABSTRACT=<sec><title>Objective</title><p>The purpose of this study was to investigate the effects of different doses of Sophora alopecuroides (SA) on the rumen fermentation and microbial diversity of sheep.</p></sec><sec><title>Methods</title><p>A total of 32 healthy Dumont crossbred male lambs weighing 25.73 ± 2.17 kg were randomly assigned to 4 treatment groups with 8 replicates each: a control group (CG) fed a basal diet with a concentrate-to-forage ratio of 7:3 and three experimental groups - the 0.1% group(TG1), 0.3% group (TG2), and 0.5% group (TG3), which were fed the same basal diet but supplemented with increasing doses of SA.</p></sec><sec><title>Results</title><p>(1) Increasing the SA dose led to a significant linear increase (<italic>p</italic>-&lt; 0.05) in acetate, propionate, butyrate, and total volatile fatty acid (TVFA) concentrations in the rumen, as well as a significant quadratic effect (<italic>p</italic>-&lt; 0.05) on the propionate concentration. In contrast, there was a significant linear decrease (<italic>p</italic>-&lt; 0.05) in the NH<sub>3</sub>-N concentration in the rumen. (2) At the level of rumen bacterial phyla, the abundance of Bacteroidetes in the rumen increased, and that of Firmicutes decreased (<italic>p</italic> = 0.08). At the genus level, the rumen abundances of Ruminococcus and Phocaeicola of sheep in the three experimental groups were significantly higher than in the control group (<italic>p</italic>-&lt; 0.05), and the abundances of Clostridiales and Candidatus-Hepatincola were significantly increased in the 0.1% and 0.3% groups (<italic>p</italic> &lt; 0.05). (3) Regarding rumen anaerobic fungi, the differences between the control group and experimental groups at the phylum level and genus level were not significant (<italic>p</italic> &gt; 0.05), but the relative abundances of Neocallimastigomycota and Piromyces in the 0.1% group were significantly higher than that in the control group.</p></sec><sec><title>Conclusion</title><p>SA addition to a high grain diet could increase the VFA concentration and pH in the sheep rumen, reduce the NH<sub>3</sub>-N concentration in the rumen and improve rumen fermentation function. Although there was no significant change in rumen bacterial or fungal diversity, SA addition increased the rumen abundances of <italic>Bacteroidetes, Ruminococcus</italic>, Phocaeicola, <italic>Clostridiales, Neocallimastigomycota</italic> and <italic>Piromyces</italic>, decreased the rumen abundance of <italic>Firmicutes</italic>, and had a positive effect on the rumen microbiota to improve sheep health.</p></sec>