Reactive oxygen species (ROS) damage mammalian sperm during liquid storage. Notoginsenoside R1 (NR1) is a compound isolated from the roots of Panax notoginseng; it has powerful ROS‐scavenging activities. This work hypothesized that the antioxidant capacity of NR1 could improve boar sperm quality and fertility during liquid storage. During liquid storage at 17°C, the supplementation of semen extender with NR1 (50 μM) significantly improved sperm motility, membrane integrity and acrosome integrity after 5 days of preservation. NR1 treatment also reduced ROS and lipid peroxidation (LPO) levels at day 5 (p <0.05). Higher glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) levels and sperm–zona pellucida binding capacity were observed in the 50 μM NR1 group than those in the control group at day 7 (p <0.05). Importantly, statistical analysis of the fertility of 200 sows indicated that addition of NR1 to the extender improved the fertility parameters of boar spermatozoa during liquid storage at 17°C (p <0.05). These results demonstrate the practical feasibility of using 50 μM NR1 as an antioxidant in boar extender during liquid storage at 17°C, which is beneficial to both spermatozoa quality and fertility.

The aim of this study was to investigate whether the addition of trehalose to cryomedia reduces cellular damage and improves gene expression in cryopreserved dairy goat testicular tissues. Testicular tissues were cryopreserved in cryomedia without or with trehalose at a concentration of 5%, 10%, 15%, 20% or 25%. Cryopreserved testicular tissues were analysed for TUNEL‐positive cell number, expression of BAX, BCL‐2, CREM, BOULE and HSP70‐2. Isolated Leydig cells from cryopreserved tissue were cultured, and spent medium was evaluated for testosterone level. The results showed that though the TUNEL‐positive cell number increased in cryopreserved testicular tissues, the presence of trehalose reduced apoptotic cell number significantly. Quantitative real‐time polymerase chain reaction results showed that although the expression of BAX was upregulated following cryopreservation, the presence of trehalose downregulates it in cryopreserved testicular tissues. Expression of BCL‐2, CREM, BOULE and HSP70‐2 was downregulated following cryopreservation but the presence of trehalose significantly upregulated their expression in cryopreserved testicular tissues. Leydig cells isolated from testicular tissues cryopreserved with trehalose produced higher testosterone than the one without it (control). These results suggest that trehalose has a protective role in cryopreservation of dairy goat testicular tissue, and the most suitable trehalose concentration for cryopreservation is 15%.