Correlation characteristics of semen quality parameters and antioxidant effect of caffeine supplemented cryopreserved Surti buck semen

Abstract

The study was done to analyze correlation characteristics between caffeine concentrations, antioxidants, oxidative stress and quality parameters in cryopreserved buck semen. Sixty-four semen ejaculates were collected from 4 Surti bucks (age>1 year) (twice/week for 8 weeks); pooled in TEYCG extender (100x106 sperms/Ml) and divided into 4 aliquots viz. T1 (Control), T2, T3 and T4 supplemented with caffeine @ 0, 1, 3 and 5 mM, respectively. They were equilibrated at 4 °C for 4 hours and cryopreserved for 24 hours. Semen quality parameters, levels for malondialdehyde (MDA) and Glutathione (GSH) were evaluated at initial, pre-freeze and post-thaw. During cryopreservation, caffeine @ 5 mM showed minimum decrease in GSH and maximum decrease in MDA but supplementation of caffeine @ 1 mM showed minimum decrease in motility, live count and host-reacted sperms. GSH and MDA were significantly (p<0.01) negatively correlated. Percent of motile, live, morphologically normal and HOST-reacted sperms had significant (p<0.01) positive correlations with GSH and significant (p<0.01) negative correlations with MDA.Correlations of caffeine concentration was significant (p<0.01) positive with GSH and significant (p<0.01) negative with MDA but non-significant with semen quality parameters. It was thus concluded that caffeine concentration in TEYCG during cryopreservation of Surti buck semen is positively correlated with antioxidant GSH and negatively correlated with oxidative stress marker MDA indicating amelioration of oxidative stress in a dose dependent manner. Caffeine concentrations do not correlate significantly with semen quality parameters but minimum decrease in motility, live count and host-reacted sperms in C2 group indicates caffeine @ 1 mM to be optimum level for preserving semen quality.