The effect of supplementation of vitamin D to the egg-yolk extender on cryopreservation of ram semen

Abstract This study aimed to examine the effects of supplementation of vitamin D to the egg-yolk extender on characteristics of frozen-thawed ram semen. Semen samples obtained from adult rams were pooled and divided into five equal volumes. It was reconstituted with extenders containing different concentrations of vitamin D (0 (control), 12.5 (VITD 12.5), 25 (VITD 25), 50 (VITD 50), and 100 ng/ml (VITD 100)) and then they were frozen. Sperm motility, plasmamembrane functionalintegrity, acrosomal integrity, DNA fragmentation and mitochondrial membrane potential of the groups were determined. Among motility values after thawing, the VITD50 group was found to be superior to the other groups ( P < 0.05 ). When the plasma membrane integrity was evaluated, VITD25 and VITD50 groups were found better than the other groups ( P < 0.05 ). Acrosomal integrity, DNA fragmentation, and mitochondrial membrane potential rates were found better in VITD25, VITD50 and VITD100 groups when compared to all other groups, but no significant difference was found among all groups ( P > 0.05 ). In the study, it was observed that adding vitamin D to the extender had a beneficial effect on ram spermatological parameters. In addition, it was concluded that the use of the 50 ng/ml vitamin D in the extender provided more effective protection than the other doses.