A technique to quantify sperm use in honeybee queens (Apis mellifera) was developed and used to analyze the number of sperm used in different groups of honeybee queens. To do this a queen was placed on a frame with worker cells containing no eggs, and an excluder box was placed around her. The frame was put back into the colony and removed after two and a half hours. This method reduced stress on the queen so that she felt comfortable enough to lay eggs and did not require the queen to be killed so that she could be sampled multiple times to look at effects of age and time after introduction into a colony. The eggs were guaranteed to be fresh and sperm number present on the egg could be counted with a fluorescence microscope by using DAPI to dye the DNA in the sperm heads. The queens were found to be very economic in their sperm use and an overall median of three sperm per egg was found. Individual queens were found to vary significantly in sperm used per egg, however no queen had a median of over ten sperm per egg. Days after introduction into the colony also had a significant effect on sperm use when looking at the queens individually and it was found that newly introduced queens used more sperm than established queens. Overall, the study shows that freshly laid eggs can be collected and sperm on these eggs can be counted directly. This is an important finding for further research into the factors affecting different patterns of sperm use and possibly for beekeepers to breed queens who use their sperm most efficiently, and who will therefore be able to maintain a successful colony for the longest time.
Biology | Entomology
Rubinsky, Maria, "Sperm Use During Egg Fertilization in the Honeybee (Apis Mellifera)" (2010). Independent Study Project (ISP) Collection. 914.