Vitamin E supplement in Tris-pumpkin seed extenders on sperm viability and fertilizing parameters of West African dwarf goat bucks chilled at 4oC.

Abstract

This study investigated the protective effects of vitamin E in Tris-pumpkin seed extenders on sperm viability and fertilizing parameters of West African dwarf goat bucks chilled at 4oC. Pooled semen from four matured WAD bucks was diluted in Tris-pumpkin extenders containing vitamin E at 0mM, 2mM, 4mM, 6mM and 8mM/100ml respectively. Microscopic assessments of diluted semen samples were carried out on sperm progressive motility, acrosome and membrane integrities, livability, sperm abnormality, arginase and acrosin activities, leukocytes, in vitro sperm capacitation and acrosome reaction after in vitro storage at 4oC for 96 hours. The concentration of malondialdehyde (MDA) in the stored semen was measured in thiobarbituric acid reactive substances. The results showed Tris- pumpkin based extender supplemented with 4mM, 6mM and 8mM inclusion levels of vitamin E had higher (p<0.05) percentage sperm progressive motility, membrane and acrosome integrities and livability compared to other inclusion level and the control group. Furthermore, Spermatozoa with Tris based extender supplemented with 2mM and 8mM inclusion levels of vitamin E had lower (p<0.05) percentage abnormality. The results showed lower (p<0.05) concentrations of MDA and leukocyte at 8mM inclusion levels of vitamin E and higher value of arginase activity at 4mM and 8mM inclusion levels. However, Tris- pumpkin extenders supplemented with 6mM and 8mM inclusion of vitamin E had highest (p<0.05) percentage of spermatozoa that underwent in vitro acrosome reaction and sperm capacitation compared to other levels and the control. The findings indicate protective potential of vitamin E on sperm viability of chilled semen stored at 4oC.