Antioxidants Significantly Improve Qinling Giant Panda (Ailuropoda Melanoleuca Qinlingensis) Sperm Quality During Cryopreservation

Abstract Background: Semen cryopreservation has become an essential tool for the reproduction and long-term preservation of giant pandas (Ailuropoda melanoleuca). However, cryopreservation is severely detrimental to sperm quality, including motility, plasma membrane, acrosome integrity, and mitochondrial activity. It is necessary to screen a effective antioxidants for improvement of sperm quality. Eight groups of antioxidants were added to the freezing medium.Results:The results showed that lycium barbarum polysaccharide (LBP), Laminaria japonica polysaccharides (LJP), or goujresveratrol (RSV) added to the freezing medium significantly improved sperm motility, acrosome integrity, and mitochondrial activity during the cryopreservation process. Furthermore, the activities of glutathione and superoxide dismutase were also improved. However, the levels of reactive oxygen species and malondialdehyde in semen were notably reduced. Regarding fertility, acrosin activity was significantly increased in LBP-treated sperm. Unfortunately, sperm viability, DNA fragmentation, and hyaluronidase activity were not significantly different between the above groups. Conclusions: LBP (2.0 mg/mL) or RSV (50 μM) are the best candidate antioxidants for inclusion in the freezing medium for improving the quality of panda spermatozoa, during semen cryopreservation.