Effect of Catalase and Superoxide Dismutase on Motility, Viability and Acrosomal Integrity of Canine Spermatozoa during Storage at 50C

Preservation of canine spermatozoa at 50C is a helpful method for dog breeding management. However, in many species, oxidative damage due to generation of reactive oxygen species (ROS) and long term storage which specifically cause DNA damage, and lipid peroxidation during preservation techniques can cause a decline of sperm motility and fertility capacity. In this study, the effect of antioxidants catalase (CAT) and superoxide dismutase (SOD) on motility, viability and acrosomal integrity of chilled canine semen were investigated. Semen was collected by digital manipulation from 4 dogs (two ejaculates/dog). After removal of seminal plasma, spermatozoa were diluted in egg yolk Tris-fructose citrate solution (EYT-FC) with or without CAT, SOD or the combination of CAT and SOD at dosages of 100, 400 and 1,600 U/ml in each antioxidant. Diluted spermatozoa were kept at 50C for 7 days. Sperm motility, viability and acrosomal integrity in the EYT-FC with CAT or/and SOD and without the antioxidants (control) were not significantly different at same point of time. At day 7, the percentage of mean compared between control and treatment groups for sperm motility were 65.6% and 65.0-66.9%, viability were 83.6% and 82.1-84.9% and acrosomal integrity were 87.2% and 85.9-88.5%, respectively. In conclusion, adding CAT and SOD or the combination of CAT and SOD in EYT-FC did not significantly improve the maintenance of motility, viability and acrosomal integrity during dog sperm storage at 50C for 7 days.