Dietary Contamination With Neonicotinoid (Clothianidin) Gradient Triggers Specific Dysbiosis Signatures of Microbiota Activity Along the Honeybee (Apis Mellifera) Digestive Tract

Abstract

BackgroundHoneybees (Apis mellifera) are facing a number of interacting stress factors affecting their general health as well as their nervous and immune systems. Recent evidence proposed the clothianidin neonicotinoid as a potential disrupting factor for the microbiota-immunity axis. In this research, we conducted in vivo experiments to measure the impact of three sublethal clothianidin concentrations (0.1, 1 and 10 ppb) on honeybee survival, syrup consumption and the honeybee gut microbiota dysbiosis. Results Clothianidin exposure significantly increased mortality in the three concentrations compared to controls. Interestingly, the lowest clothianidin concentration was associated to the highest food intake and the highest mortality. Clothianidin exposure significantly induced variation in the taxonomic composition of the gut microbiota. The co-abundance network analysis reveals local dysbiosis signatures specific to each gut cohorts (midgut, ileum and rectum) driven by specific taxa.Conclusions Our findings confirm that clothianidin exposure triggers a disruption of the honeybee’s symbiotic defense systems such as resistance to colonization, translating into a surge of potentially pathogenic taxa. Furthermore, the importance of low activity taxa with weak transcriptional activity in maintaining a stable honeybee gut microbiota. Finally, the early detection of gut dysbiosis in honeybee is an early promising alarming signal towards a microbiome approach in hive management the impact for assessing the impact of sublethal xenobiotics exposure.