Effects Of Gallic Acid On Quality Of Boar Semen During Normal Temperature Preservation

Boar semen preserved at normal temperature is the first choice of artificial insemination in production,With the prolongation of storage time,the accumulation of ROS in semen and the growth and reproduction of microorganisms will cause oxidative stress and attack the polyunsaturated fatty acids on the sperm membrane,which will cause damage to the sperm plasma membrane and acrosome.The growth and reproduction of microorganisms will also cause agglutination and damage of sperm,which will affect the sperm activity and fertilization ability.Gallic acid(GA)is a kind of natural phenolic acid,which has strong antioxidant capacity.It has been approved to be used as antioxidant in food.Besides antioxidant,gallic acid also has antibacterial capacity,and has significant inhibitory effect on Gram-negative bacteria such as E.coli.In this study,different concentrations of gallic acid(0,5,7,9,11 mg/L)were added into BTS diluent to dilute fresh boar semen,which was then stored in a 17 ℃ incubator according to the group.At different times,sperm viability,A + B grade sperm count,sperm membrane integrity,mitochondrial membrane potential,antioxidant capacity were measured by microscope and computer-aided sperm analyzer In addition,the content of the microorganism in the semen of different preservation time was determined to explore the effect of gallic acid on the normal temperature preservation of boar semen.The optimum concentration of gallic acid was selected and compared with the antioxidant vitamin C and antibiotic gentamicin.The main results of this study are as follows:1.The addation of different concentrations(0,5,7,9,11,9 mg/L)of gallic acid to boar semen extender improved semen quality preserved at 17℃ to different degrees.on the preservation 1-3th day effect is not significant(P > 05),3-10 d concentrations gallic acid has different degree of protection to the boar semen,add 9 mg/L of gallic acid significantly increased the sperm living rate,A + B grade sperm count,plasma membrane and acrosome integrity and mitochondrial potential(P < 0.05),in the preservation rate of 10 th day live live sperm rate reached 62.9% significantly higher than that of control group(P < 0.01),prolonged the semen to save time.In addition,9 mg/L gallic acid can significantly increase the antioxidant levels of SOD,CAT and T-AOC in semen(P < 0.05),and significantly reduce the content of ROS and MDA in semen(P < 0.05).2.The addition of 9 mg/L gallic acid and vitamin C into the semen can improve the semen preservation quality,and the sperm viability,A+B sperm count,plasma membrane and acrosome membrane integrity rate were all improved,but the sperm viability,A+B sperm count,plasma membrane and acrosome integrity rate in the 9 mg/L group were significantly higher than those in the vitamin C group at 5-10 th day(P < 0.05).The activity of SOD,CAT and other antioxidant enzymes in semen of gallic acid group was significantly higher than that of vitamin C group at the later stage of preservation,and the content of ROS and MDA was also significantly lower than that of VC group.The mitochondrial membrane potential of the 9 mg/L gallic acid group was also significantly lower than that of the vitamin C group(P < 0.05)and significantly lower than that of the blank group(P < 0.01).3.The gallic acid is added in the semen and gentamicin the live rate and acrosome membrane integrity in the preservation 1-3th day effect is not significant(P > 05),5-10 th day,9 mg/L gallic acid preserved effect is significantly higher than the rest of the group(P < 0.05),plasma membrane integrity in the preservation 3-10 th day,9 mg/L gallic acid preservation effect is significantly higher than that of gentamicin group,gentamicin group was significantly higher than that of blank group(P < 0.05).The bacterial content in semen of gallic acid group was not significantly different from that of the blank group(P > 0.05),and was significantly lower than that of gentamycin group(P < 0.05).In summary,adding gallic acid,vitamin C and gentamicin to semen can significantly improve the quality of normal temperature preservation of pig semen.The protective effect and antioxidant capacity of gallic acid on pig semen are stronger than vitamin C,the effective preservation time of semen is extended to the 10 th day,and the activity rate reaches 63.07%.There was no significant inhibition of gallic acid on the bacterial content in semen,and the bacterial content was significantly lower than that in gentamicin group.