Structural differences in the gut microbiome of bats using terrestrial vs. aquatic feeding resources

Abstract

AbstractBat gut microbiomes are adapted to the specific diets of their hosts. Despite diet variation has been associated with differences in bat microbiome diversity, the influence of diet on microbial community assembly have not been fully elucidated. In the present study, we used available data on bat gut microbiome to characterize the microbial community assembly of five selected bat species (i.e.,Miniopterus schreibersii,Myotis capaccinii,Myotis myotis,Myotis pilosus, andMyotis vivesi), using network analysis. These bat species with contrasting habitat and food preferences (i.e.,My. capacciniiandMy. pilosuscan be piscivorous and/or insectivorous;Mi. schreibersiiandMy. myotisare exclusively insectivorous; whileMy. vivesiis a marine predator) offer an invaluable opportunity to test the impact of diet on bat gut microbiome assembly. The results showed thatMy. myotisshowed the most complex network, with the highest number of nodes, whileMy. vivesihas the least complex structured microbiome, with lowest number of nodes in its network. No common nodes were observed in the networks of the five bat species, withMy. myotispossessing the highest number of unique nodes. Only three bat species,My. myotis,My. pilosusandMy. vivesi, presented a core microbiome and the distribution of local centrality measures of nodes was different in the five networks. Taxa removal followed by measurement of network connectivity revealed thatMy. myotishad the most robust network, while the network ofMy. vivesipresented the lowest tolerance to taxa removal. Prediction of metabolic pathways using PICRUSt2 revealed thatMi. schreibersiihad significantly higher functional pathway’s richness compared to the other bat species. Most of predicted pathways (82%, total 435) were shared between all bat species, whileMy. capaccinii,My. myotisandMy. vivesi, but noMi. schreibersiiorMy. pilosus, showed specific pathways. We concluded that despite similar feeding habits, microbial community assembly can differ between bat species. Other factors beyond diet may play a major role in bat microbial community assembly, with host ecology, sociality and overlap in roosts likely providing additional predictors governing gut microbiome of insectivorous bats.