Study On The Chicken Freezing Semen By Pellets And Straws Using DMA As Cryoprotectants

The conservation of poultry genetic variation plays a key role in poultry breeding material,saving land in living bodies and protecting biodiversity.Recently,but the glycerin tubule freezing technology is complex,the DMA pellets is not conducive to long-term preservation of semen,and the logo is not convenient.For DMA cryoprotectants,this study adopts single cock semen,designed the four tests: 1)to study the four breeds,including the black chicken,the hunan native princess chicken,the White Leghorns and the partridge shank chicken,to explore the differences of individual and individual semen freezing resistance in different periods;2)the comparative trial used the diluted semen from the black chicken and hunan native princess chicken was divided into A,B group,and adding the different processed DMA to A,B group(A group:adding directly DMA;B group:adding DMA in the diluent and freezing);3)compared DMA pellets and straw frozen semen in the black chicken and hunan native princess chicken;4)adding hydrogen peroxide(Catalase,CAT),lycopene,lycopene,LP,n-acetyl cysteine(NAC)and N-Acetyl-L-cysteine,which it has a protective effect to black chicken frozen semen.The experiment result shows as follow.1.The research of the diversity about semen antifreezeBy the test more than three months,the same person made the research about frozen semen in total 609 times of with the same kind of detection method in 45 chicken of different breed(black chicken,the hunan native princess chicken,the White Leghorns and the partridge shank chicken).the result shows that: the frozen sperm activity exists the difference between the individuals,species,and same individual in different periods.The frozen sperm of black chicken has averagely the best activity(0.5)among four breeds,on the contrary,white leghorns(0.38)and the partridge shank chicken are worst,and hunan native princess chicken is better.The experiment is concluded that the cock of the sperm frost resistance exists difference among the varieties,the different individual of same breed,the same individual in different periods semen.2.The research of the methods to adding the DMASubjects black chicken and hunan native princess chicken,semen dilution as 1:1,and microscopy,leaving qualified semen balance 30 min,divided two groups,A group directly add 6% of the DMA(need to compute the DMA content);B group(the DMA added in dilution according to the concentration of 18% before the trial,then cryopreservation,thawing in the process of experiment)added directly contains the DMA diluent,adding proportion is 1-0.5.The experiment result shows:there are not significant difference between the A group and B group,but compared A group,the sperm vitality in B group is more strong.The B Group add DMA after diluted,which can reduce the DMA poisonous attack to semen,improve the sperm vitality after frozen,and simplify operation substantially.3.The comparative study of DMA chicken semen frozenThe experimental method is optimal DMA additive that is cryoprotective agents,and the same semen made into pellets and straw at the same time,and contrasting them.The result shows that compared the DMA pellets in the black chicken and hunan native princess chicken,the sperm vitality of frozen DMA is slightly higher in DMA pellets.At the same time,the DMA straw highest fertilization rate reached 77.61%,and hatching rate 71.64% through three artificial insemination in black chicken,this experiment will DMA straw optimization,establishing the cryopreservation technology of the DMA straw in chicken semen.4.The study of the function of antioxidants protecting the frozen chicken semenAdopting the black chicken as experimental object,the qualified semen by microscopic examination was divided into equivalently the 4 to 5 parts,then adding antioxidants(CAT,NAC and N-Acetyl-L-cysteine)according to the different concentration,testing the sperm vitality after frozen thawed and the fertilization rate after fertilization.The results shows that the protective effect added the CAT,LP and NAC in the freezing solution to chickens semen freezing is not obvious.The experiment was conducted to comparative study for the individual difference of frozen semen with the DMA as cryoprotectants,the method of production system and the antioxidant protection forth so on,innovating the add method of cryoprotectants and save method containing cryoprotectants diluent,the fertilization rate about DMA optimized tubule frozen sperm has been in the domestic leading level,the production method of tubule sperm is simple and cheap,meanwhile,taking up the international leading level.