Study On Three Polysaccharides And Equilibrium Time For Crypreservation Of Bull Semen

Bull semen freezing and artificial insemination technology had been developing quickly since 1980s , they were widely used for practical application. In order to improve bull sperm freezing– thawing, optimize freezing procedure, protect and improve the bull semen's ability of rejecting hypothermia, we used cryoprotectant( such as Radix Phodiolae Polyose,Sodium Alginate,trehalose) and bull semen freezing diluting equilibrium time as content of this study, took sperm viability, sperm motility, mitochondrial activity, plasma membrane integrity and acrosome integrity as evaluation index, utilized propidium iodide(PI),rhodamine 123,HOST and Peanut Agglutinin(PITC-PNA)which was connected with fluorescein isothiocyanate to respectively detect the index mentioned above, also studied the effects of Radix Phodiolae Polyose,Sodium Alginate,trehalose on the SOD,LHD and GOT activity of bull semen after freezing and thawing, we got results as following:During the semen freezing procedure, we added 6% Radix Phodiolae Polyose, 6% Sodium Alginate, 4% trehalose into traditional diluent TCG, and these groups could improve sperm viability, sperm motility, mitochondrial activity, plasma membrane integrity and acrosome integrity comparing with control group, among them the effect of 6% Sodium Alginate was the best and the difference with control group was significant(p<0.05). The freezing effects were Sodium Alginate > Radix Phodiolae Polyose > trehalose.Match two of Radix Phodiolae Polyose,Sodium Alginate,trehalose respectively, then added them into diluent, studied the mutual freezing protection effects of Radix Phodiolae Polyose,Sodium Alginate,trehalose on bull sperm . The results showed that the group which were added 0.04mg/mL Radix Phodiolae Polyose and 0.4mg/mL Sodium Alginate was the best , compared with control group ,it could significantly improve sperm viability, sperm motility, mitochondrial activity, plasma membrane integrity and acrosome integrity (p<0.05).During the semen freezing procedure, the activity of SOD gradually decreased from fresh sperm, sperm freezing to sperm thawing, the activity of LHD and GOT were gradually increasing. The groups which were respectively added 0.06mg/mL Radix Phodiolae Polyose,0.6mg/mL Sodium Alginate and 0.4mg/mL trehalose were better then the other treatment groups and control group (P<0.05). Among them 0.06mg/mL Radix Phodiolae Polyose group was the best , the activity of SOD had improved 7.13% compared with control group after equilibrium, improved 27.81% after thawing; LDH had decreased 5.56% after equilibrium, decreased 12.5% after thawing; GOT had decreased 4.14% after equilibrium, decreased 11.07% after thawing.In order to overcome the decreasing of bull sperm quality and freezing effects, we set the first timing of diluting equilibrium time as : 60min,90min,120min and 150min;the second timing were: 30min,45min,60min and 75min,took 4h(first step 2h,second step 2h) as control and proceeded crossover trial. We found the freezing effects of first diluting equilibrium 90 min and the second diluting equilibrium 45 min were better then others, sperm motility, sperm viability, plasma membrane integrity, mitochondrial activity, and acrosome integritywere higher then the other treatment groups and control group, respectively increased 11.41%,10.96%,10.41%,10.81% and 15.99%(P<0.05).