The effect of taxifolin on cold shock damages in spermatozoons induced by sperma freeze process in rabbit

In this study, it was aimed to investigate the effect of taxifolin (TAX) added to rabbit semen on cold-shock damages in spermatozoa induced by freezing. For this purpose, semen was collected from 6 adult New Zealand rabbits once a week with the help of artificial vagina. The collected semen were pooled at 38 °C and divided into 4 equal volumes. They were diluted with TAX-free (Control group), 50 μM (TAX-50 group), 100 μM (TAX-100 group) and 200 μM (TAX-200 group) TAX-containing tris + egg yolk extender at 38 °C and their temperatures were lowered to 4 °C. Following equilibration, semen drawn into 0.25 mL straws were frozen in an automatic semen freezing device and stored in liquid nitrogen container at -196 °C. The analyses for motility, kinematic parameters, morphological deformities, changes in membrane integrity, mitochondrial membrane potential, dead-live ratio, acrosomal disorders and as well as oxidative stress analyses were performed on semen that were thawed in 38 °C water for 25 seconds. Addition of 50 μM TAX provided significant improvements in motility (total, progressive, rapid and static), high mitochondrial membrane potential and the ratios of spermatozoa with acrosomal damage compared to control. When compared to the control, malondialdehyde (MDA) levels in the TAX-50 and TAX-100 groups were found to be significantly lower, while the MDA level was high and viable spermatozoa ratio was low in the TAX-200 group. On the other hand, there was no significant difference between the groups in terms of kinematic parameters, morphological deformities, membrane integrity and antioxidant levels. As a result, it was observed that the low dose of TAX had a positive effect and the high dose had a negative effect. Therefore, it was concluded that the addition of low-dose (50 μM) TAX to the extenders would be a useful additive in reducing cold-shock damage that occurs during freezing of rabbit semen.