Uncovering the Fecal Bacterial Communities of Sympatric Sika Deer (Cervus nippon) and Wapiti (Cervus canadensis)

SIMPLE SUMMARY: There are many microbial communities in the digestive tracts of animals, and the complex gut microbiome constitutes an intricate ecosystem and intestinal microbial community which has co-adapted with its host. The intestinal microecology plays an important role in the host’s maintenance of normal physical activities, such as substance metabolism, energy transmission, signal transduction, and the immune system. This study used high-throughput sequencing technology to sequence the fecal microbiota of sika deer (Cervus nippon) and wapiti (Cervus canadensis) in order to explore the composition of, and the similarity between, the fecal microbiota structures of sika deer and wapiti in the similar living environment. The species composition, relative abundance of fecal microbiota, alpha diversity, and differences in beta diversity were analyzed. The maintenance of the composition of the gut microbiota and a balanced intestinal environment through the diet plays a key role in maintaining the host’s health. The results demonstrate that the fecal microbiota of sika deer and wapiti share a similar fecal microbiota structure, but there was some evidence showing that the gut microbiota of these two animals exhibit a clear divergence at the species level. ABSTRACT: Microbial symbiotic associations may be beneficial, neutral, or harmful to the host. Symbionts exploit the host space and nutrition or use hosts as carriers to spread to other environments. In order to investigate the fecal bacterial communities of wild sika deer (Cervus nippon) and wapiti (Cervus canadensis), this study aimed to sequence and explore the composition of, and similarity between, the fecal microbiota of sika deer and wapiti using high-throughput sequencing. The composition and relative abundance of fecal microbiota, alpha diversity, and differences in beta diversity between the two species were analyzed. We found that no pathogenic bacteria were present in large quantities in the hosts. The dominant bacterial phyla found in the two deer species were similar and included Firmicutes, Bacteroidetes, Proteobacteria, and Spirochaetes. Moreover, the deer also shared similar dominant genera, including the Rikenellaceae RC9 gut group, Ruminococcaceae_UCG-010, Ruminococcaceae_UCG-005, and Bacteroides. These results demonstrate that the sika deer and wapiti share a similar fecal microbiotal structure, probably due to their common diet and living environment, but there was some evidence of a difference at the species level. These analyses provide new insights into the health status of deer populations outside protected environments and offer a scientific framework for monitoring the health conditions of sika deer and wapiti.