Effects of avocado seed extract (ASE) in different tris-extenders on sperm and seminal oxidative stress indices of vitrified spermatozoa of West African Dwarf (WAD) goats during vitrification were assessed. Semen samples were diluted with varying levels (0, 5, 10, 15 and 20 mL/100 mL of diluent) of ASE in tris citric acid (TCA), tris sodium phosphate (TSP) and tris sodium citrate (TSC) extenders while a tris-extender without citric acid, sodium phosphate and sodium citrate served as control. Diluted semen samples were vitrified and preserved. The results revealed higher (P<0.05) progressive sperm motility in TCA extenders at 10%, 15% and 20%, and TSP extender at 20% ASE. Acrosome integrities were higher (P<0.05) in the different tris-extenders at 15% and 20% ASE. TCA, TSP and TSC extenders had higher (P<0.05) membrane integrities at 10%, 15% and 20% ASE. TSP extenders had higher (P<0.05) live sperm at 20% ASE. TCA extenders had higher acrosome reaction while TSP at 20% ASE and TSC at 15% and 20% of ASE had higher sperm capacitation. TCA extender at 20% ASE had reduced malondialdehyde (MDA) concentrations while higher acrosin activities were observed at 20% ASE in TCA extender (P<0.05). The findings indicated that 20% ASE in the tris-extenders improved sperm and oxidative stress indices and the tris-extenders were ranked best in this order: TCA > TSP > TSC.

Effects of mucuna seed extract (MSE) in tris-extenders on sperm functional integrities and seminal oxidative stress indices of vitrified sperm of West African Dwarf (WAD) goat bucks were investigated. Varying levels (0, 0.25, 0.5, 0.75, 1 g/100 mL of diluent) of MSE in tris-extenders were diluted with semen specimens. Diluted semen specimens were vitrified and preserved in liquid nitrogen. The results showed that sperm functional integrities (acrosome and membrane integrities) in MSE extenders were comparable. However, seminal oxidative stress indices (malondialdehyde [MDA] and acrosin activity) differed (P<0.05) among the various treatments and the control. The results revealed that semen vitrified with MSE had reduced (P<0.05) MDA concentrations compared to the control. Higher (P<0.05) acrosin activities were recorded in semen vitrified with MSE compared to the control except at 0.25g MSE and optimal values were recorded at 1g MSE. The findings indicated that MSE in the tris-extenders reduced MDA concentration with congruent elevated acrosin activity and consequently maintained sperm functional integrities of vitrified spermatozoa of the WAD goat.