Brood termination rate in honey bees in two consecutive brood cycles: a comparison

Semi-field studies of honey bee (Apis mellifera L.) colonies provide an important mean of assessing the effect of chemical exposure on brood development. Brood termination rate (BTR) is a common metric for evaluating effects of exposure; however, the index can be variable thereby limiting the extent to which studies can detect treatment-related effects. This study evaluated whether BTR in successive brood cycles differs between the enclosure phase vs monitoring phase of semi-field studies. The data indicate that for controls, differences were not statistically different; however, for colonies exposed to the reference toxicant fenoxycarb, BTR was significantly (p < 0.05) higher during the enclosure phase compared to the monitoring phase.