Location: Bee Research LaboratoryTitle: Direct effect of acaricides on pathogen loads and gene expression levels of honey bee Apis mellifera) Author
Submitted to: Journal of Insect Physiology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/21/2011
Publication Date: 12/28/2011
Citation: Boncristiani, H., Underwood, R., Schwarz, R.S., Evans, J.D., Pettis, J.S., Vanengelsdorp, D. 2011. Direct effect of acaricides on pathogen loads and gene expression levels of honey bee Apis mellifera. Journal of Insect Physiology. 58:613-620. Interpretive Summary: Honey bees are needed for pollination services worldwide. The primary threat to honey bees worldwide is the varroa mite. Here we deterime the impacts of chemicals in use for controlling the varroa mite on honey bee physiology. We show a change in stress- responses by honey bees after exposure to two different treatments, and present a general protocol to test for the effects of chemiclas and other streses on bee health. The results have implications for colony collapse disorder and other widespread colony losses, and will help beekeepers manage bees more effectively against the threat of varroa mites.
Technical Abstract: The effect of using miticides to control varroa mites has long been a concern to the beekeeping industry due to unintended negative impacts on honey bee health. Irregular ontogenesis, immune defense suppression, impairment of normal behavior are some of the described symptoms for the use of pesticides. Often, external stressors such as pathogens impair conclusive results about pesticide effects on honey bee metabolism. This is the case for Varroa destructor, a mite that negatively affects honey bee health on many levels, from direct parasitism which weakens honey bee energy stores to vectoring and/or activation of pathogens including many viruses. Here we present a gene expression profile, comprising genes acting on diverse metabolic levels (detoxification, Immune system and development), in a rare population that lacks the influence of varroa mites. We present data for hives treated with five different miticides, Apiguard (Thymol), Apistan (tau-fluvalinate), Checkmite (Coumaphos), Miteaway (Formic acid) and Tactic (Amitraz). The results indicate that some miticides trigger metabolic responses, altering detoxification gene expression pathways, components of immune system responsible for cellular response and JNK pathway, and development genes, potentially interfering with the health of individual bees and colonies.