Effects of Pyruvate and Taurine for In Vitro Preservation in Boar Semen and the Developmental Rates of Embryos Fertilized by Semen Treated with Antioxidant

Oxidative stress is one of the major causes of failure in in vitro storage of boar semen. Reactive oxygen species (ROS) are known to be important mediators of such stress. The present study examined the effects of pyruvate and taurine on sperm motility and expression of BAD, Cytochrome c, Caspase-3 and Cox-2 protein in in vitro storage of boar semen, and tested the effect of semen treated with antioxidant with or without hydrogen peroxide on the development of IVM/IVF porcine embryos. Semen samples were transported to the laboratory at $17^{\circ}C$ within 2 hr after collection and were treated with different concentration of pyruvate $(1\~10mM)$ and taurine $(25\~100mM)$ with or without 250uM $H_2O_2$ respectively. The supplementation of pyruvate and taurine increased sperm motility in boar semen during in vitro incubation at $37^{\circ}C$. Expression of apoptosis protein (BAD, cytochrome c, caspase-3 and cox-2) were reduced in the group of boar semen treated with pyruvate and taurine when compared to the other groups. The developmental rates of IVM/IVF porcine embryos fertilized by semen treated with pyruvate and taurine were significantly increased when compared to control (P<0.005). These results indicate that supplementation of pyruvate and taurine as antioxidants in boar semen extender can improve the semen quality and increase in vitro development of porcine IVM/IVF embryos when boar semen treated with antioxidants was used for in vitro fertilization.