Effects of sublethal doses of clothianidin and/or V. destructor on honey bee (Apis mellifera) self-grooming behavior and associated gene expression

摘要

Little is known about the combined efects of stressors on social immunity of honey bees (Apis mellifera)and related gene expression. The interaction between sublethal doses of a neurotoxin, clothianidin, andthe ectoparasite, Varroa destructor, was examined by measuring diferentially expressed genes (DEGs)in brains, deformed wing virus (DWV) and the proportion and intensity of self-grooming. Evidencefor an interaction was observed between the stressors in a reduction in the proportion of intensegroomers. Only the lowest dose of clothianidin alone reduced the proportion of self-groomers andincreased DWV levels. V. destructor shared a higher proportion of DEGs with the combined stressorscompared to clothianidin, indicating that the efects of V. destructor were more pervasive than thoseof clothianidin when they were combined. The number of up-regulated DEGs were reduced with thecombined stressors compared to clothianidin alone, suggesting an interference with the impacts ofclothianidin. Clothianidin and V. destructor afected DEGs from diferent biological pathways but sharedimpacts on pathways related to neurodegenerative disorders, like Alzheimer’s, which could be relatedto neurological dysfunction and may explain their negative impacts on grooming. This study shows thatthe combination of clothianidin and V. destructor resulted in a complex and non-additive interaction.