Cryosurvival of goat spermatozoa in tris-egg yolk extender supplemented with vitamin E
The effect of vitamin E supplementation in tris-egg yolk extender on sperm parameters of West African Dwarf (WAD) goat bucks was determined. Tris-egg yolk extenders supplemented with different levels of vitamin E (2, 4, 6 and 8 mM) were diluted with semen samples. The diluted semen samples were cryopreserved for 30 days and thereafter evaluated for sperm quality parameters. The results showed higher (P<0.05) sperm motility, acrosome integrity, membrane integrity, live sperm, acrosome reaction and capacitation, and reduced sperm abnormality in extenders supplemented with vitamin E compared to the control. These parameters were better sustained in extenders supplemented with 6 mM and 8 mM (P<0.05). Lower concentrations of malondialdehyde (MDA) were observed at 6 mM and 8 mM compared to the control (P<0.05). Higher percentages of acrosome reaction and capacitation were observed in extenders supplemented with vitamin E compared to the control (P<0.05). Optimal percent (P<0.05) of acrosome reaction and capacitation were observed in extenders supplemented with 6 mM and 8 mM of vitamin. The findings revealed that supplementation of vitamin E at 6 mM and 8 mM in tris-egg yolk extenders were effective for improving sperm parameters of WAD goat bucks during cryopreservation.
Keywords: Antioxidants, bucks, freezing, oxidative stress, sperm