AUTHOR=Song Chun , Zhang Tiantian , Xu Duhan , Zhu Mingming , Mei Shihui , Zhou Bijun , Wang Kaigong , Chen Chao , Zhu Erpeng , Cheng Zhentao 

TITLE=Impact of feeding dried distillers’ grains with solubles diet on microbiome and metabolome of ruminal and cecal contents in Guanling yellow cattle

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1171563

DOI=10.3389/fmicb.2023.1171563

ISSN=1664-302X

ABSTRACT=<p>Dried distillers’ grains with solubles (DDGS) are rich in nutrients, and partially alternative feeding of DDGS effectively reduces cost of feed and improves animals’ growth. We used 16S rDNA gene sequencing and LC/MS-based metabolomics to explore the effect of feeding cattle with a basal diet (BD) and a Jiang-flavor DDGS diet (replaces 25% concentrate of the diet) on microbiome and metabolome of ruminal and cecal contents in Guanling yellow cattle. The results showed that the ruminal and cecal contents shared the same dominance of <italic>Bacteroidetes</italic>, <italic>Firmicutes</italic> and <italic>Proteobacteria</italic> in two groups. The ruminal dominant genera were <italic>Prevotella_1</italic>, <italic>Rikenellaceae_RC9_gut_group</italic>, and <italic>Ruminococcaceae_UCG-010</italic>; and the cecal dominant genera were <italic>Ruminococcaceae_UCG-005</italic>, <italic>Ruminococcaceae_UCG-010</italic>, and <italic>Rikenellaceae_RC9_gut_group</italic>. Linear discriminant analysis effect size analysis (LDA &gt; 2, <italic>P</italic> &lt; 0.05) revealed the significantly differential bacteria enriched in the DDGS group, including <italic>Ruminococcaceae_UCG_012</italic>, <italic>Prevotellaceae_UCG_004</italic> and <italic>Anaerococcus</italic> in the ruminal contents, which was associated with degradation of plant polysaccharides. Besides, <italic>Anaerosporobacter</italic>, <italic>Anaerovibrio</italic>, and <italic>Caproiciproducens</italic> in the cecal contents were involved in fatty acid metabolism. Compared with the BD group, 20 significantly different metabolites obtained in the ruminal contents of DDGS group were down-regulated (<italic>P</italic> &lt; 0.05), and based on them, 4 significantly different metabolic pathways (<italic>P</italic> &lt; 0.05) were enriched including “Linoleic acid metabolism,” “Biosynthesis of unsaturated fatty acids,” “Taste transduction,” and “Carbohydrate digestion and absorption.” There were 65 significantly different metabolites (47 were upregulated, 18 were downregulated) in the cecal contents of DDGS group when compared with the BD group, and 4 significantly different metabolic pathways (<italic>P</italic> &lt; 0.05) were enriched including “Longevity regulating pathway,” “Bile secretion,” “Choline metabolism in cancer,” and “HIF-1 signaling pathway.” Spearman analysis revealed close negative relationships between the top 20 significantly differential metabolites and <italic>Anaerococcus</italic> in the ruminal contents. Bacteria with high relevance to cecal differential metabolites were <italic>Erysipelotrichaceae_UCG-003</italic>, <italic>Dielma</italic>, and <italic>Solobacterium</italic> that affect specific metabolic pathways in cattle. Collectively, our results suggest that feeding cattle with a DDGS diet improves the microbial structure and the metabolic patterns of lipids and carbohydrates, thus contributing to the utilization efficiency of nutrients and physical health to some extent. Our findings will provide scientific reference for the utilization of DDGS as feed in cattle industry.</p>