Prolonging holding time of boar semen increases sperm antioxidant capacity and frozen-thawed quality.

Cryopreservation of boar semen causes oxidative damage to sperm. Semen needs to hold at 17°C for a period of time prior to cryopreservation. Holding time allows interaction between sperm and seminal plasma to improve sperm quality after thawing. The aim of this study was to investigate the effect of prolonging holding time of collected boar semen on sperm antioxidant capacity and frozen-thawed quality. Collected semen was held at 17°C for 3 hours and 24 hours respectively. A part of the semen was irradiated with ultraviolet (0.6 J/cm²), and the remaining semen was cryopreserved. The semen samples were evaluated sperm motility, viability, mitochondrial membrane potential (MMP) and acrosome integrity. Besids, the sperm malondialdehyde (MDA) level was measured after being irradiated with ultraviolet. The results showed that the sperm motility, viability, and MMP of ultraviolet irradiated or frozen-thawed semen held at 17°C for 24 hours were significantly higher (P < 0.05) than those of 3 hours holding time. The ultraviolet irradiated sperm MDA level of 24 hours holding time was significantly lower (P < 0.05) than that of 3 hours. In summary, boar semen holding at 17°C for 24 hours could effectively reduce ultraviolet irradiated sperm MDA level and the oxidative damage to sperm, and improve the sperm quality of frozen-thawed semen. [ABSTRACT FROM AUTHOR]