Captivity plays a role in shaping the gut microbiome of social mammals

Abstract

With its roles in nutrition, behavior and immunity, the gut microbiome is an important health factor among mammals living in captivity. Recent studies have shown that the composition of the mammalian gut microbiome is altered by environmental changes associated with built, enclosed environments; these changes could explain certain negative health outcomes experienced by captive mammals. Because of the novelty surrounding the impacts of captivity, our study takes interest in understanding the effects of captivity on mammals that typically live in social groups in the wild. We hypothesized that being held captive, away from the social structure of the wild, affects the gut microbiome composition of mammals, and that such differences would vary by sociality and social group size. Our diversity analyses captured significant differences between social and non-social mammals, and between captive and wild social mammals, with respect to gut microbial alpha diversity. Taxonomic analysis showed that captivity had a greater effect on the number of unique microbial phyla in social mammals compared to non-social mammals. Differential abundance analysis identified Proteobacteria, Actinobacteria, Euryarchaeota and Fusobacteria as the main phyla responsible for observed differences between the gut microbiomes of captive and wild social mammals, with potential health implications that could be explored.