| Estrus synchronization and mulitiple ovulation are the most determinative component elemen in the domestic animal embryo transfer technique.Therer is very important significance in the stock farming produce of the estrus synchronization , it can be promote the utilize of frozen semen generally,concentrate the undertake artificial insemination,improve domestic animal oestrous cycle and oestrus appearance,as well as increase domestic animal productivity;The crucial point for embryo transfer technique is the same physiological condition of donor and receptor by estrus synchronization in order to offer the normal development physiological environment for embryos.It can reveals the female physiologic adjustment mechanism by control female synchronization of estrus artificially and study its breed physiology.It can get a great quantity superiority individual embryos by superovu -lation and artificial insemination,and then transfer these embryos to receptors, so superiority genealogy female progeny size increased quickly,at the same time shorten generation interva, enhanced selection intensity ,bring the better female into full play in the breeding,as well as accelerated breeding process in domestic farm animals. Our results indicate that:Estrus synchronization technique programs of CIDR+PMSG+HCG and CIDR+PMSG were established in the non-breeding seasons about local hybridization caprine.The percentage about local hybridization sheep of estrus was 90 after treated with estrus synchronization, the group A which used ram to examine estrus was 82.5%, the group B which used vaginal examination was 97.5%.The percentage of pregnancy about the A1+B1 which injected HCG when mated was 94.44%,and the control group was 88.89%,but the distinction was not significantly.The peak time of estrus in the non-breeding seasons appears 24～48h, and the best time of breeding is 60～70h after remove cork by vaginal examination.In the experiment of mulitiple ovulation ,the treatment sequence used CIDR+PMSG+HCG for the offsprings of pure breed Suffolk, Poll Dorset, and Doper ewes in the non-breeding seasons was established. The percentage of superovulation reaction rate was 94.12%,97.56% and 94.74%, respectively, The percentage of pregnancy was 86.67%,62.96% and 86.36%,the average embyoes number gotten from one was 7.80, 6.80, and6.33, the average embryos number gotten from three species was 6.89. The highest embyos number gotten from Poll Dorset was 20.The embryos from Suffolk, Poll Dorset, and Doper offsprings were transplanted into northeast fuzz sheep and hybridization sheep treated estrus synchronization,the transplanted pregnancy rate was 71.05%,74.26%, and71.43%, respectively. The fresh embryo conception rate transplanted from three species was 72.22%. Finally 34 northeast fuzz sheep yeaned 55 lambs and 44 hybridization sheep yeaned 66 lambs, but there was no significant difference which came from receptors to yean(P>0.05). This demonstrated that embryo transfer played important role in variety improvement and breeding work.The weight which came from receptor made the different to the the birth and wean weights,the birth and wean weights(65 d) of the kids from big receptors(≥55Kg)were heavier than that from small ones( < 55Kg)(P<0.05),This indicated that the birth weight and developments of the kids related to the recipientsπweight.As above-mentioned, estrus synchronization, mulitiple ovulation, artificial insemination and embryo transfer were used in the experiments,The aims were investigate main points and operational procedures of those techniques, establish and optimize operating manual of embryo transfe, search for key point of embryo transfe which fit to the northeast, increase the rate of genetic improvement.As well as provided the approach, line and experiment evidence for increasing fineness breed and industrialization of embryo transfer.
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