Effect of Vitamin E supplementation on semen quality and the testicular cell membranal and mitochondrial antioxidant abilities in Aohan fine-wool sheep

Thirty male Aohan fine-wool sheep (5 months of age) with similar body weight were procured from the Aohan fine-wool sheep breeding farm of Inner Mongolia Autonomous Region, China. The sheep were divided randomly into five groups, which were labeled as Group 1, 2, 3, 4 and 5 and supplemented respectively with 0, 20, 200, 1000 or 2400 IU sheep−1 d−1 Vitamin E, for 12 months, respectively. Three Aohan fine-wool sheep in each group were selected randomly for semen collection at the age of 16 months, then slaughtered at 17 months to collect the testis sample for testicular cell membranal and mitochondrial antioxidant abilities analysis. The results showed that supplementing Vitamin E at the concentration of 200 IU sheep−1 d−1 in diets may have a positive effect in increasing semen quality and quantity (P < 0.05), significantly reduce malondialdehyde (MDA) level and improve the activities of superoxide dismutase (SOD)and glutathione peroxidase (GSH-PX) in testicular cell membrane and mitochondria (P < 0.05). In conclusion, the present study demonstrated that that supplementing Vitamin E can have a positive role in improving semen quality via protecting testicular cell membrane and mitochondria from antioxidant abilities. However, the optimal level of Vitamin supplement has still to be determined.