Fecal and gut microbiota of honey bees

The establishment of stable gut microbial communities is essential to honey bee health. Yet, the modes of acquisition and transmission of the gut microbiota are to be confirmed. The gut of honey bees is colonized by symbiotic bacteria after their emergence from their wax cells as adults. It becomes remarkably stable and consistent across individual bees within five days. Few studies suggested bees could be in part colonized via contact with fecal matter in the hive. 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 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. It also implies that contact of young bees with fecal matter in the hive is a plausible route for gut microbiota acquisition.