Effects of cold storage prior to freezing on superoxide dismutase, glutathione peroxidase activities, level of total reactive oxygen species and sperm quality in dogs.

Reactive oxygen species (ROS) are one of several crucial factors that cause mammalian sperm damage during handling and preservation. Their deleterious effects can be restricted by the action of antioxidants. The present study aimed at investigating: (i) effects of cold storage prior to freezing on activities of enzymatic antioxidants (superoxide dismutase; SOD and glutathione peroxidase; GPx) and level of total reactive oxygen species (tROS); and (ii) effects of SOD or SOD plus GPx supplementation to chilled (3 and 96 h) and frozen-thawed semen.