Effects of trehalose supplementation on post-thaw sperm quality of honey bee drones

Abstract

Sperm cryopreservation has led to an increase in widespread use and has it made it more practical to use artificial insemination not only for domestic animals but also for non-mammalian species and humans. Dimethyl Sulfoxide (DMSO) was the most frequently used cryoprotectant by protecting honey bee drone semen when freezing it. The objective of this study was to determine the effects of Trehalose (0.05M, 0.1M or none at all) on extending the viability of semen with 12% DMSO that was based on sperm motility and plasma membrane functional integrity of frozen drone semen. Three different freezing extender solutions were designated as follows; the 0.05M Trehalose, 0.1M Trehalose and Trehalose free (control group). Semen motility and plasma membrane functional integrity were evaluated under phase-contrast microscopy (400X). We found that in control group, DMSO is a critical substance in freezing extender and supports post-thaw sperm motility (53%) and plasma membrane functional integrity (79%) to some extent. Addition of 0.05M Trehalose to the extender leads to a small recovery of post-thaw motility (55%) and plasma membrane integrity (89%), but when Trehalose is added at 0.1M concentration, this led to significantly better post-thaw motility (62%) and plasma membrane integrity (91%). In conclusion, the freeze-thaw process is detrimental to post-thaw drone semen viability. The addition of 0.1 or 0.05M Trehalose to the freezing media containing 12% DMSO has been seen better post-thaw cell motility and plasma membrane integrity of spermatozoa.