Beneficial Effects of the Mitochondria‐Targeted Antioxidant <scp>MitoQ</scp> on Bull Semen Post Cryopreservation Quality Characteristics

This experiment evaluated the effects of increasing MitoQ concentrations in semen extender on post-thaw quality of Holstein bull sperm, including motility, membrane integrity, antioxidant status and viability. Semen samples were collected, pooled and diluted with extender containing 0 (control), 5, 50, 500 and 1000 nM of MitoQ and frozen through the standard procedure. An increase in MitoQ supplementation positively influenced total and progressive motility, as well as average path velocity; however, these effects were not statistically significant until the concentration reached 50 nM. The highest MitoQ level (1000 nM) showed no difference from the control group. Supplementation of semen extender with 50 and 500 nM of MitoQ significantly increased sperm membrane integrity and mitochondrial activity. Sperm viability improved significantly in concentrations of 5, 50 and 500 nM of MitoQ compared to control, whereas 1000 nM of MitoQ did not show any difference from the control group. Moreover, MitoQ significantly reduced MDA level regardless of its concentration. The concentrations of 50 and 500 nM of MitoQ significantly reduced ROS concentration. It can be concluded that 50 and 500 nM of MitoQ in extender can improve sperm quality parameters in bull semen.