| description |
The mammalian microbiota in the gastrointestinal tract (GIT) play important roles in host nutrition and health, while few studies has investigated microbial diversity, interactions and community stability across the GIT in wild mammals. Using 16S rRNA gene sequencing, we analyzed the bacterial diversity, network interactions and ecosystem stability across five gut chambers (mouth, stomach, small intestine, caecum and colon) from two common pika (Ochotona spp.) species in China, including Plateau pikas (O. curzoniae) from high-altitude regions and Daurian pikas(O. daurica) from low-altitude areas. The relative abundances of dominant Firmicutes and Bacteroidetes had an increasing trend from mouth to colon. Caecum and colon harbored higher bacterial diversity compared with other anatomical regions. Gut region significantly influenced the structure of bacterial communities in the GIT. Notably, the mouth or stomach community structure was highly similar between Plateau pikas and Daurian pikas, while the bacterial communities from small intestine, caecum or colon showed significant differences between host species. The cecal bacterial community of Plateau pikas was more conserved than that of Daurian pikas. Network analysis indicated that topological features showed marked variations among gut regions or between host species. Interestingly, the ecosystem stability of bacterial communities decreased gradually from mouth to colon. Our results suggested that gut region and host species influence the diversity, structure, and network interactions of bacterial communities in pika digestive tract. For hindgut-fermenting mammals, relatively higher bacterial diversity and ecosystem stability in the caecum may provide a favorable condition for the fermentation of plant polysaccharides. |