Levels of hemolymph sugars and body glycogen of honeybees ( Apis mellifera L.) from colonies preparing to swarm

Abstract

For honeybees, the process of swarming and establishment of a new colony is energetically costly. However, HPTLC analysis of the concentration of hemolymph carbohydrates and spectrophotometric quantification of body glycogen reserves of worker honeybees from colonies experimentally induced to swarm revealed no differences from those of similar aged worker bees from normal colonies. In contrast, mass and sugar concentration of the honey sac contents were significantly higher in worker bees from pre-swarm colonies rearing queens compared to worker bees from normal or crowded colonies without sealed queen cells. The proximate cause of honey sac engorgement was not determined, though these results suggest that queen rearing may serve as a stimulus for honey sac engorgement during swarm preparation. Hormonally mediated carbohydrate homeostasis and pre-swarm utilization of assimilated sugars for wax biosynthesis are both discussed as possible mechanisms responsible for relative constancy of the concentration of hemolymph sugars.