| Anhui white goat is one of the most famous Native Goats breeds due to its high fecundity, wide adaptability and so on. The cryopreserved semen of Huanghuai white goat goat can be used to accelerate the speed of conservation. The present study was to find good diluent ingredients and cryopreservation procedure for Anhui white goat,and paves the way to practical applications for freezing semen.In this present study, five experiments were carried out:cryopreservation procedure optimization, buffer optimization, Additive effect of DMFanf SDS. The results were summarized as follows:1.we selected four factors from cryopreservation procedure:proportion of dilution, equilibration time, thawing media , the thawing temperature and used the orthogonal design to find the best procedure of freezing-thawed.Every factors selected three levels, proportion of dilution:1︰2(A1),1︰3(A2).1︰4(A3); equilibration time:2h(B1),3h(B2),4h(B3); thawing media: glucose 3-3(C1),vitamin B12(C2),2.9% of sodium(C3); thawing temperature: 40℃(D1),50℃(D2),60℃(D3). We selected motility rate,index of survive, aerosome intact integrate rate,membrane integrate rate as the criteria of thawing semen quality.The result show that:1) three levels of dilution have no differences(P<0.05),but the median R of A3 is higher than others; 2)the motility rate and aerosome intact integrate rate of B2 is better than B3 and B1 respectively(P<0.05),but membrane integrate rate of B2 is worse than B3(P<0.05);3)the motility rate of C1 is better than C2(P<0.05).the membrane integrate rate of C1 is better than C2 and C3(P<0.05).the aerosome intact integrate rate of C1 is batter than C3(P<0.05);4)the motility rate of D1 is better than others(P<0.05).The result display that the best procedure of freezing-thawed is diluted by 1:4, equilibrated 3h,used B12 and 40℃to thaw.2.The selection of buffer has three steps.First,we selected four buffers(E:sodium,F:Tris,G:pipes,H:hepes) and designsed three levels for every factors (E:0.2g,1.6%,3.0%;F:0.02%,2.42%,4.36;G:0.1%,0.5%,1.0%;H :0.1%,0.5%,1.0%)to find better buffer compose by the orthogonal experiments of L9(34). The result display that the better buffer compose is E:0.2%, F: 2.42%;G: 0.5%;H :0.5%. Secondly, according the result of first step,we designsed another three levels for four factors(E:0.1g%,0.2%,0.3%;F:1.8%, 2.4%,3.0;G:0.2%,0.5%,0.8%;H :0.2%,0.5%,0.8%) to find better buffer compose by the orthogonal experiments of L9(3~4).We used composite index as the the judgement of the quality of semen . The result display that E(sodium)and H(hepes)was better than anothers.Thirdly, The result display that the better buffer compose of E:1.6% and H:1.6% was the best.3.We attempted to use a mixing cryoprotectant with DMF and glycerol in varing proportions to provide better protection for freezing goat spermatozoa. The results showed that the mixed cryoprotectant (5% glycerol and 1% DMF) provided better protection for freezing goat spermatozoa than those of other treatment groups(P<0.05).4.In this experiment,the goat sperm was frozen in extrender containing 0.05%,0.1%,0.15%,0.2%,0.25%,0.3%SDS respectively. The best results about motility, aerosome intact and membrane integrity were obtained with SDS at 0.1% ( 65.9%) , 0.2% (58.46%) and 0.1%(54.13%) respectively. The result display that 1% SDS is the best one.5. In order to further evaluate the effectiveness of such protocol, fifty-five of goats were taken for artificial insemination. The results showed that forty-two female Anhui White goats had not non-return after three oestrums(namely determined pregnant) and the pregnant rate was 76.4%.In conclusion, the basic diluent ingredients and the procedure of goat semen cryopreservation are optimized. The optimal basic diluent consists 3% glucose,1.6% citric acid,1.6%hepes,5%glycerol,1%DMF,0.1%SDS,20% yolk。The optimal procedure improved Anhui white goat semen motility to 0.65 after thawed.
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