Seasonal analysis of the gut microbiota in adult and young captive Asian black bears in northeast China: supplementary material

Seasonal alternation impacts the composition of gut microbiota in wild and free-ranging bears, but little is known concerning captive bears. In this study, we investigated the effects of seasonal changes on gut microbiota in captive Asiatic black bears (Ursus thibetanus). Fecal samples of thirteen adult and young were collected at a bile farm in Northeast China between September 2017 and January 2018. The fecal microbiota community was analyzed by sequencing the bacterial 16S V4 hypervariable region using a next-generation sequencing platform. We found that Firmicutes was the predominant phylum in the feces of captive Asiatic black bears. Microbial alpha and beta diversity in both adult and young captive Asiatic black bears was significantly different between the two time points. At the genus level, the relative abundance of Sarcina was increased in all of the captive Asiatic black bears in January, while Streptococcus was decreased in young but not adults. Overall, the composition of gut microbiota was influenced by seasonal changes, but the effect was more pronounced in young captive Asiatic black bears. These findings may help to better understand the roles of captivity and hibernation on shaping the gut microbiota in bears.