Effects Of Salvianic Acid A And Rosmarinic Acid On Quality Of Boar Semen During Normal Temperature Preservation

Dilution and preservation of semen are the key links in artificial insemination technology.While boar semen preserved at normal temperature,which is widely used in pig artificial insemination,will be affected by warious factors during the preservation process.As the preservation time is prolonged,the quality of semen will continue to decline,and one of the important factors is the damage to sperm caused by excessive accumulation of reactive oxygen species(ROS)in semen.An appropriate amount of ROS in semen has a certain physiological promoting effect on sperm,while excessive ROS will cause pathological damage to sperm and affect the normal function of sperm.Therefore,it is an important method to supplement antioxidants to boar semen extender to improve the antioxidant capacity of semen,thus effectively reducing the oxidative stress of sperm caused by excessive ROS.Both salvianic acid A and rosmarinic acid are natural phenolic acids with good antioxidant activity.In this study,salvianic acid A and rosmarinic acid with different concentrations were added to the medium-effect of self-prepared semen extender respectively.The sperm motility,plasma membrane integrity,acrosome integrity,mitochondrial membrane potential,total antioxidant capacity(T-AOC),superoxide dismutase(SOD)activity,catalase(CAT)activity,malondialdehyde(MDA)content,ATP content and glyceraldehyde-3-phosphate dehydrogenase(GAPDH)activity were measured at different times of boar semen preservation at 17 ? to explore the effects of these two antioxidants on boar semen quality,and the optimum addition concentration was screened out.Furthermore,the best compatibility was selected through the combination of different concentrations of these two antioxidants to optimize the formula of semen dilution powder.The main results of this study are as follows:1.The addation of different concentrations(1,5,10,25,50,100 ?mol/L)of salvianic acid A to boar semen extender improved semen quality preserved at normal temperature.Among them,adding 25 ?mol/L salvianic acid A had the best effect,which significantly improved the sperm motility,plasma membrane integrity,acrosome integrity,ATP content,mitochondrial membrane potential as well as GAPDH activity(P < 0.05).Sperm motility,plasma membrane and acrosome integrity were 61.83%,57.80% and 71.95% respectively on the 9th day of preservation,and the effective preservation time of semen reached 9 days.Adding 25~100 ?mol/L salvianic acid A could effectively improve the level of T-AOC as well as SOD activity,and significantly reduce MDA content(P < 0.05).In addition,adding 25 ?mol/L salvianic acid A significantly improved the CAT activity on the 7th day of semen preservation(P < 0.05).2.Rosmarinic acid with different concentrations(20,40,60,80,100,120 ?mol/L)added to boar semen extender improved semen quality preserved at normal temperature.Among them,the addation of 40 ?mol/L rosmarinic acid had the best effect,which significantly improved sperm motility,plasma membrane integrity,acrosome integrity,the level of T-AOC,SOD activity,ATP content,mitochondrial membrane potential as well as GAPDH activity of sperm,and significantly reduced MDA content(P < 0.05).Sperm motility,plasma membrane and acrosome integrity were 66.47%,63.31% and 73.77% respectively on the 9th day of preservation,and the effective preservation time of semen reached 9 days.However,different concentrations of rosmarinic acid added to semen extender had no significant effect on CAT activity(P > 0.05).3.In the compatibility test of salvianic acid A and rosmarinic acid with different concentrations,the sperm motility,plasma membrane and acrosome integrity of C4 combination were significantly higher than that of the two added separately(P < 0.05),and the succinodehydrogenase(SDH)activities of C4 and C5 combinations reached 65.00 U/mL on the 7th day,which were significantly higher than that of the two added separately(P < 0.05).In addition,the level of ROS could be reduced to a certain extent in C4 combination compared with the two added separately,while the level of ROS in C8 combination has an increasing trend compared with the control group,which promoted the generation of ROS to a certain extent.Therefore,the best compatible concentration of salvianic acid A and rosmarinic acid is C4 combination,i.e.25 ?mol/L salvianic acid A and 40 ?mol/L rosmarinic acid.In summary,certain concentrations of salvianic acid A and rosmarinic acid can effectively improve the quality of boar semen preserved at 17 ? and prolong the storage time.When added separately,the optimal concentrations of salvianic acid A and rosmarinic acid were 25 ?mol/L and 40 ?mol/L respectively,the effective storage time of semen was prolonged to 9 days,and the sperm motility reached 61.83% and 66.47% respectively.When added together,the compatibility of 25 ?mol/L salvianic acid A and 40 ?mol/L rosmarinic acid could play a better role than the effect of two added separately,which improved the sperm motility to 68.59% on the 9 th day of preservation and further improved the preserved semen quality.