AUTHOR=Rehemujiang Halidai , Yusuf Hassan Ali , Ma Tao , Diao QiYu , Kong Luxin , Kang Lingyun , Tu Yan 

TITLE=Fermented cottonseed and rapeseed meals outperform soybean meal in improving performance, rumen fermentation, and bacterial composition in Hu sheep

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1119887

DOI=10.3389/fmicb.2023.1119887

ISSN=1664-302X

ABSTRACT=<sec><title>Background</title><p>This study examined the effects of substituting cottonseed meal (CSM) or rapeseed meal (RSM) for soybean meal (SBM) on Hu sheep performance, rumen fermentation, and bacterial composition. 51 four-month-old indigenous male Hu sheep with starting body weights of 22.51 ± 2.84 kg and similar origins were randomly assigned to three treatments; (1) non-fermented total mixed ration (TMR) with SBM (CK), (2) fermented TMR containing CSM (F-CSM group), and (3) fermented TMR containing RSM (F-RSM group).</p></sec><sec><title>Results</title><p>The three groups’ intake of dry matter differed significantly (<italic>p</italic> &lt; 0.05). In terms of average daily gain, the F-RSM group outperformed the CK and F-CSM groups (<italic>p</italic> &lt; 0.05). The pH of the rumen was substantially lower in the CK group than in the F-CSM and F-RSM groups (<italic>p</italic> &lt; 0.05), and the F-CSM group had greater amounts of volatile fatty acids (VFA) than the F-RSM and CK groups. In comparison to the CK group, the microbial crude protein yield was significantly higher in the F-CSM and F-RSM groups (<italic>p</italic> &lt; 0.05). The F-CSM group significantly outperformed the F-RSM group of pepsin and cellulose enzyme activity (<italic>p</italic> &lt; 0.05). The relative abundance of <italic>Bacteroidetes</italic> was greater in the CK and F-RSM groups compared to the F-CSM group (<italic>p</italic> &lt; 0.05). In comparison to the other groups, <italic>Firmicutes</italic> were less abundant in the CK group (<italic>p</italic> &lt; 0.05). <italic>Prevotella</italic> was present in a higher relative abundance in the F-CSM and F-RSM groups than in the CK group (<italic>p</italic> &lt; 0.05). <italic>Prevotella</italic> was greater in relative abundance in the F-CSM and F-RSM groups than in the CK group (<italic>p</italic> &lt; 0.05). The relative abundances of <italic>Veillonellaceae_UCG-001</italic> and <italic>Lachnospiraceae_XPB1014</italic> correlated with rumen butyric acid content and NH<sub>3</sub>-N content (<italic>p</italic> &lt; 0.05). Gene function prediction revealed that replacing SBM with F-CSM or F-RSM in the diet of Hu sheep can promote glycan biosynthesis and metabolism.</p></sec><sec><title>Conclusion</title><p>The replacement of F-CSM and F-RSM for SBM has an influence on the richness and diversity of rumen bacteria at the phylum and genus levels. Replacement of SBM with F-CSM increased VFA yield and further promoted the performance of Hu sheep.</p></sec>