Effect of different anaesthesia treatments on the onset of oviposition by virgin queen honey bees

Abstract

Treating instrumentally inseminated honey bee queens with carbon dioxide accelerates egg laying. This treatment also activates the ovaries of virgins. The aim of the study was to compare the effect of three different treatments: (1) anaesthesia with carbon dioxide, (2) anaesthesia with nitrogen, and (3) oxygen deprivation by submersion in water, on the onset of oviposition in virgin queens. The effect of the number and duration of CO2 treatments was also investigated. No significant differences were found in the onset of egg laying in queens treated with CO2, or N2, or water. The beginning of oviposition after the CO2 treatment for 0.1, 1, 2, and 10 min, did not differ significantly. Whether a CO2 treatment was performed twice or three times, the effect was the same, but oviposition was accelerated compared to when only one anaesthesia treatment was used. I speculate that ovary activation in queens is not the effect of CO2 or any other gases but rather the effect of a lack of oxygen, i.e., anoxia.