Effect Of Different Factors On Cold Storage Of Semen Of Inner Mongolia Cashmere Goat

Semen preservation is the key to goat artificial insemination technology.Semen preservation can extend the survival time of sperm,improve the breeding efficiency of fine breeds,thus laying a foundation for the industrialization of goat.At present,cold storage of goat semen is still one of the main preservation methods in goat production.In the process of semen cold storage,different diluent formula,seminal plasma content and different anti-cold protectant will affect the cold storage of semen to a great extent.In this experiment,the cold storage effects of five diluent formulations on semen of Inner Mongolia cashmere goat were compared.Then the effect of different dilution methods(high-fold dilution(1:10),low-fold dilution(1:2),centrifugal washing(removal of seminal plasma)),different seminal plasma contents(0、10%、20%、30%and 40%)and the effect of different liquid exchange methods(half liquid exchange or full liquid exchange)on cold storage of goat semen were compared.Finally,based on the optimum formula,the different cold protectants(egg yolk,soy lecithin and skim milk)on goat semen cold storage were studied.The results are as follows:1.After five days cold storage of goat semen,among five different diluent formulas,the preservation result using " formula 3" was best.sperm viability was 48.96%,acrosome integrity was 51.70%,plasma membrane integrity was 40.11%,mitochondrial membrane integrity was 46.56%,which were significantly higher than those of other diluent formulas(P<0.05).Therefore,the " formula 3" was used as the basic diluent medium for subsequent experiments.The main ingredients of "formula 3" was as follows:Tris 300mM,glucose 56mM,citric acid 95mM,fructose 80.6mm,NaHCO3 14.9mm,HEPES 25.4mm,ATP 15.7mm,penicillin 50IU/mL,streptocin 100mg/mL,egg yolk 10%.2.After five days cold storage of goat semen,sperm motility,velocity of movement and plasma membrane integrity in the high-fold dilution group were significantly higher than the low-fold dilution group and the centrifugal washing group(P<0.05).Supplement of seminal plasma into diluent medium can significantly improve preservation of goat semen,the relative optimal seminal plasma concentration was 10-20%(v/v).sperm motility in half liquid exchange group was significantly higher than that of full liquid exchange group and contro group.3.After five days cold storage of goat semen,After adding different cold protectant in diluent medium,all the indexes of sperm in egg yolk group and soybean lecithin group were significantly higher than that of skim milk group(P ＜0.05),but no significant difference between the former two group(P>0.05),while the indexes of sperm in soybean lecithin group slightly higher than that in egg yolk group,which sperm motility was 48.18%,straight-line velocity(VSL),curve velocity(VCL)and average path velocity(VAP)were 68.33um/s,92.30um/s and 85.06um/s respectively,acrosome integrity was 53.15%,the plasma membrane integrity was 43.03%,the mitochondria membrane integrity was 50.09%.Therefore,the present study suggested that soy lecithin could be an effective cold protectant in goat semen cold storage.