The Influence of Body Weight on Semen Parameters in Apis mellifera Drones

SIMPLE SUMMARY: Knowledge and management of parental forms in bees as in other species is one of the important tools of selection and/or breeding programs. The study of honey bee drone semen may be relevant in relation to the productivity of honey bee colonies. Today, more than ever, we realize the importance of pollinators and their fine balance with the environment. Despite the importance of this aspect, currently we have less knowledge on this subject compared to other species. An adequate investigation and evaluation of the quality of the semen in relation to body weight could open new opportunities regarding its integrity, functionality and conservation in order to increase economic efficiency and maintain biodiversity in optimal conditions. ABSTRACT: The quantity and quality of the honey bee drone semen have a significant determination on the performance of bee colonies. The existence of a smaller number of mature drones to participate in the mating of queens, as well as a sufficient number of drones but with poor quality semen can have serious implications for the productivity of bee colonies. Our study aimed to investigate the correlation between two body weight ranges of drones and semen parameters in the Buckfast honey bee, data that could be integrated into the optimization of instrumental insemination in been queens. Semen was collected from two groups of drones with different body weights (200–240 mg and 240–280 mg). Semen volume, semen concentration, motility, morphology and membrane integrity of spermatozoa were analyzed. The phenotype indicator related to body weight in correlation with the main semen parameters studied gives a weak influence or causality ratio. In drones with 240–280 mg body weight, a higher percentage of spermatozoa with abnormal morphology (>9.60%) was recorded, compared to drones with 200–240 mg body weight. The study reveals that a higher weight of honey bee drones is correlated with higher sperm concentration and total number of spermatozoa/ejaculate, with an increase in the percentage of spermatozoa with abnormal morphology.