Plasma Lipid Peroxidation as a Marker for Seminal Oxidative Stress in Stallion

Abstract

This experiment aims to evaluate the correlation between lipid peroxidation levels in serum and seminal plasma in equines. Also, it investigates the lipid peroxidation in extended semen samples and its effects and sperm motility during a 72 hr refrigeration period. Blood and semen were collected from fertile Crioulo stallions. Serum and seminal plasma lipid peroxidation levels were analyzed by thiobarbituric acid reactive substances (TBARS) immediately after semen collection. After addition of extender (hour = 0), diluted semen was refrigerated and stored at 5 °C. Semen analyses, TBARS and catalase activity were performed in extended semen at 0, 24, 48, and 72 hours. We noted that levels of plasma lipid peroxidation can be used as an indicative of seminal oxidative stress. Also, lipid peroxidation does not increase substantially during semen storage. Lipid peroxidation and the antioxidant enzyme catalase do not seem to be the major cause of loss and motility and consequently reduction in fertility in stallion semen during storage for 72 h at 5 °C.