Nicotinamide mononucleotide enhances semen quality during chilled storage of maguan hornless goat: mitigating oxidative damage at 4 °C

As a rare and endangered genetic resource unique to China, the Maguan hornless goat faces many challenges in terms of population protection and breeding. Chilled semen preservation is a key method for short-term gene exchange, but it can easily cause sperm cold shock and oxidative stress, thereby damaging sperm quality. This study investigated the protective effects of different concentrations of nicotinamide mononucleotide (NMN) on Maguan hornless goat semen stored at 4 °C for 72 h. The results showed that 3 mM NMN significantly improved sperm motility after 72 h of chilled storage, better maintained sperm plasma membrane integrity, delayed apoptosis, increased intracellular ATP levels and mitochondrial membrane potential, protected acrosome integrity, and enhanced sperm antioxidant capacity. Collectively, 3 mM NMN supplementation effectively maintains sperm motility and cellular structural and functional stability during chilled storage, providing new insights into the mechanism by which goat sperm are protected from oxidative damage during chilled storage.