Fecal transplant allows transmission of the gut microbiota in honey bees

Abstract The gut of honey bees is colonized by symbiotic bacteria during the first days of adult life, once bees have emerged from their wax cells. Within five days, the gut microbiota becomes remarkably stable and consistent across individual bees. Yet, the modes of acquisition and transmission of the gut microbiota are to be confirmed. Few studies suggested bees could be colonized via contact with fecal matter in the hive and via social interactions. However, the composition of the fecal microbiota is still unknown. It is particularly unclear whether all bacterial species can be found viable in the feces and can therefore be transmitted to newborn nestmates. Using 16s rRNA gene amplicon sequencing we revealed that the composition of the honey bee fecal microbiota is strikingly similar to the microbiota of entire guts. We found that fecal transplantation resulted in gut microbial communities largely similar to those obtained from feeding gut homogenates. Our study shows that fecal sampling and transplantation are viable tools for the longitudinal analysis of bacterial community composition and host-microbe interactions. Our results also imply that contact of young bees with fecal matter in the hive is a plausible route for the acquisition of the core gut microbiota.