Evaluation of the Effect of Trehalose–DMSO-Based Cryopreservation Medium on the Motility Characteristics of Honey Bee Drone Spermatozoa in Combination with Different Antioxidants

Honey bees (Apis mellifera) are the main pollinators of many plant species, particularly agricultural crops. The concern over Colony Collapse Disorder of bee colonies in recent years necessitates the use of new approaches for their conservation in in situ and ex situ conditions. Modern techniques for cryopreservation of drone spermatozoa allow for the preservation of their genetic diversity. Some of the challenges in the field of cryopreservation are the alterations induced by the low temperatures, including morphological disruptions, plasma membrane integrity, formation of reactive oxygen species, DNA fragmentation, loss of motility, mitochondrial activity and viability, early hyperactivation, depletion of proteins from the acrosome region, premature capacitation, reduced sperm–oocyte fusion, and the occurrence of other cellular cryoinjuries. The objective of the current study is to contribute to the ongoing efforts in identifying substances added to semen extenders aimed at inhibiting cryogenic-induced changes. Our study investigates the impact of antioxidant supplements, scilicet vitamins C, vitamin E, and L-carnitine, on attenuating the adverse effects of cryogenic storage on drone spermatozoa. Using a Computer-Assisted Sperm Analysis, we evaluated the effectiveness of various antioxidants added to the extender in maintaining sperm motility parameters following liquid nitrogen storage. The data indicated significant differences in sperm traits among treatments with supplements after post-thawing. These findings emphasize the advantageous contribution of these added antioxidants within semen extenders for drone spermatozoa in preserving sperm quality parameters. The establishment of novel protocols for cryogenic storage of honey bee drone spermatozoa, incorporating low-cytotoxicity additives, is of utmost importance for the conservation of this endangered species.