BACKGROUND

The ectoparasitic honey bee mite Varroa destructor is one of the main causes related to the gradual decline of honey bees Apis mellifera. Nowadays, beekeepers utilize a wide range of different synthetic acaricides, organic acids and essential oils to keep mite populations under control. A previous work had shown that pirimicarb could be a new varroacide candidate. The aim of this study was to observe the chronic effects on worker honey bees feeding activity after an oral exposure to 1.05 mM of pirimicarb. Long-term effect of a 24 hours exposition to pirimicarb were also tested.

RESULTS

After three successive trials were performed, no mortality could be detected at the tested concentration, oral exposure to pirimicarb had significant effect on honey bees feeding behavior. Pirimicarb added to a sucrose solution led to a rapid decrease of food intake. These tendencies may be reversed when the pesticide is removed. However, the recovery seemed to be trial-dependent.

CONCLUSION

The study highlights a seasonal variation of honey bee's susceptibility which should be considered in toxicology studies in general.