Exploring the potential of the insect gut-brain axis to modulate the hygienic behaviour of Western honey bees (Apis mellifera)
Abstract
The Western honey bee, Apis mellifera, is vulnerable to disease, especially disease afflicting the brood. To counter this, bees exhibit hygienic behaviour: nurse bees detect olfactory cues indicative of disease and remove affected pupae. Selecting for this trait is challenging for beekeepers, who may instead resort to quick-fix antibiotics. In this thesis, I explore the potential of beneficial bacteria (“probiotics”) to promote hygienic behaviour. I fed bees two species of lactic acid-producing bacteria that may help synthesize olfactory-associated neurotransmitters, then tested for changes in hygiene and microbial diversity. I detected small increases in hygiene and small changes to microbiota composition in the short term, but these treatment effects were generally small and variable. This research nonetheless provides a foundation for a field study with more power to detect small but potentially significant differences through the bee gut-brain axis, which could ultimately serve the beekeeping community by providing recommendations for best practices.