Cryopreservation of Bali Bull Semen in CEP Diluent with the Addition of Various Antioxidants

Cryopreservation of semen was a crucial technology in livestock breeding; however, it compromised sperm quality due to oxidative stress, lipid peroxidation, and structural damage. This study aimed to determine the effect of adding α-tocopherol and glutathione antioxidants in Caudal Epididymal Plasma (CEP) diluent on the quality of frozen Bali bull semen. Four groups of CEP semen diluents were prepared with different antioxidant supplementation: P1 (CEP), P2 (CEP + 2 mM α-tocopherol), P3 (CEP + 0.75 mM glutathione), and P4 (CEP + 2 mM α-tocopherol + 0.75 mM glutathione), while Tris Egg Yolk extender was used as a comparator (P5). Semen collected from two Bali bulls was evaluated before and after the freezing and thawing processes using parameters such as motility, viability, membrane integrity, lipid peroxidation (MDA), and DNA integrity. The results showed that the P2 group supplemented with 2 mM α-tocopherol had the highest post-thawed motility, viability, and membrane integrity compared to other groups (P