Quercetin Supplementation in Tris Egg Yolk Extender Improves the Post-Thaw Quality of Zaraibi Buck Semen

Abstract

This study investigates the effect of adding various concentrations of quercetin (QUE) on the post-thaw semen quality of Zaraibi bucks. Semen was collected from seven bucks, examined, and dispensed into five portions, where each portion was diluted with Tris egg yolk extender supplemented with 0 μM as a control, 10 μM, 15 μM, 25 μM, and 40 μM of QUE per mL of semen extender. The diluted portions were loaded into mini-straws, sealed, and frozen in liquid nitrogen. Frozen-thawed straws were evaluated for sperm progressive motility, kinematic parameters, viability, plasma membrane, and acrosome integrity. Also, seminal superoxide dismutase (SOD), glutathione peroxidase (GPX), and total antioxidant capacity (TAC) levels and malondialdehyde (MDA) content were assessed. Our results revealed that the extender supplemented with 25 μM QUE has significantly (P<0.05) higher CASA sperm progressive motility, curve line, straight line, and average path velocities than the control. The sperm viability, plasma membrane, and acrosome integrity of the 25 and 40 μM QUE groups were markedly higher (P<0.05) compared to those of the control group. SOD and GPX levels were substantially higher (P<0.05) in semen samples supplemented with 25 μM QUE, while TAC was significantly greater (P<0.05) in 15, 25, and 40 μM QUE groups. Conversely, MDA content was markedly lower (P<0.05) in 25 μM QUE. In conclusion, adding 25 μM QUE in the freezing extender enhances post-thaw buck semen quality via minimizing reactive oxygen species production and lipid peroxidation, as evidenced by the obtained higher sperm characteristics and enzymatic antioxidant activity.