AUTHOR=Ma Yuhao , Deng Xiaotian , Yang Xue , Wang Jiankui , Li Tun , Hua Guoying , Han Deping , Da Lai , Li Rui , Rong Weiheng , Deng Xuemei 

TITLE=Characteristics of Bacterial Microbiota in Different Intestinal Segments of Aohan Fine-Wool Sheep

JOURNAL=Frontiers in Microbiology

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.874536

DOI=10.3389/fmicb.2022.874536

ISSN=1664-302X

ABSTRACT=The microbial community performs vital functions in the intestinal system of animals. Modulation of the gut microbiota structure can indirectly or directly affect gut health and host metabolism. Aohan fine-wool sheep grow in semi-desert grasslands in China and show excellent stress tolerance. In this study, we amplified 16S rDNA gene to investigate the dynamic distribution and adaptability of the gut microbiome in the duodenum, jejunum, ileum, cecum, colon, and rectum of Aohan fine-wool sheep. The results showed that the microbial composition and diversity of the ileum and the large intestine (collectively termed the hindgut) were close together, and the genetic distance and functional projections between them were similar. Meanwhile, the diversity index results revealed that the bacterial richness and diversity of the hindgut were significantly higher than those of the foregut. The abundance and diversity of bacterial species increased from the foregut to the hindgut, and the dominant bacteria changed from Proteobacteria to Bacteroidetes. This may be due to differences in the physiological environment and function of each intestinal segment. In functional analysis, Succiniclasticum was found to be a biomarker of the foregut and was involved in succinic acid metabolism. The catechol and citrate metabolic pathways are more active in the foregut, which may contribute to the production of biosynthetic precursors, such as pyruvate and acetyl-CoA, increasing the level of energy synthesis and metabolism in the foregut. Ruminococcaceae and Caldicoprobacteraceae as hindgut biomarkers can perform degradation of cellulose polysaccharides in the large intestine and produce beneficial metabolites. Moreover, Coriobacteriaceae and Eggthellaceae are involved in flavonoid metabolism and polyphenol production. Interestingly, these unique biomarker bacteria have not been reported in Mongolian sheep or other sheep breeds. Collectively, the gut microbiota of Aohan fine-wool sheep is one of the keys to adapting to the semi-desert grassland environment. Our results provide new insights into the role of gut microbiota in improving stress tolerance and gut health in sheep.