CRYOSURVIVAL OF GOAT SPERMATOZOA IN TWO TRIS BASED EXTENDERS SUPPLEMENTED WITH VITAMIN E

Abstract

Tris Coconut Water (TCW) and Tris Skim Milk (TSM) extenders supplemented with different levels of vitamin E were studied for their ability to support in vitro cryosurvival of spermatozoa obtained from West African Dwarf (WAD) goat bucks. Semen samples collected with the aid of artificial vagina were diluted with two tris extenders supplemented with 2, 4, 6 and 8mM of vitamin E for 30 days in liquid nitrogen. Spermatozoa cryopreserved with 6mM and 8mM inclusion levels of vitamin E for TCW extenders and 8mM inclusion levels of vitamin E for TSM based extenders had highest (P < 0.05) percentage motility. However, the results showed highest (P < 0.05) percentage acrosome integrity and membrane integrity at 4mM, 6mM, and 8mM inclusion levels of vitamin E in TCW extender. Highest (P< 0.05) percentage live spermatozoa were observed at TSM extenders supplemented with 4mM, 6mM and 8mM inclusion levels. Spermatozoa cryopreserved with 6mM and 8mM TCW extenders had the lowest (P < 0.05) percentage abnormality. Moreover, TCW and TSM extenders supplemented with 6mM and 8mM of vitamin E had highest (P < 0.05) spermatozoa that underwent acrosome reaction and capacitation. The findings indicated that spermatozoa obtained from WAD goat bucks were better preserved in TCW extender.