In Vivo Production And Cryopreservation Of Embryo In Beef Cattle

The expanding field of embryo transfer can be viewed as the female counterpart of artificial insemination. Synchronization of the estrous cycleis the first step in ET. It has progressed from prolonging or reducing the leteal phase to modifying ovarian follocular waves with FSH. A novel approach uses the protocol of P+FSH+PG to improve synchrong of ovulation and timed insemination without the detection of estrus. Cryopreservation techology is gradually replacing the age-old method the simple method of vitrification. The ability to freezers, to freeze and thaw embryo with very little detrimental effect on their survival facilitates not only routine ET but also has led to an international trade in frozen embryos of cattle. Beside, the export of embryos is safer and cheaper than exporting live animals or semen. Remarkable progress has been made during the past decade in the refinement of procedures for induction of ovulation, synchronization of estrus, in vivo and in vitro production and Cryopreservation of embryos. The nonsurgical techniques and laparoscopy for routine embryo transfer have accelerated the growth of embryo transfer technology in farm animals.32CH, LM, SM cattle were selected as donors and devided into 3 groups, on the same condition of feeding system, these donors were superovulated with the following treatments: CIDR + FSH 10mg + PG (I group), CIDR + FSH 18mg + PG (II group), and CIDR + FSH 21.6mg + PG (III group) . In addition, crypreservation of embryo was used for two methods. The results showed that the superovulation effects(excellent embryo:9.22)of SM cattle of 1 group were batter than that of II, III group, they had singicant difference(p<0.05); the superovulation effects (excellent embryo: 9.60) of LM cattle of II group were batter than that of I, III group, they had singicant difference (p<0.05); the superovulation effects (excellentembryo: 9.13) of CH cattle of II group were batter than that of I, III group, they had singicant difference (p<0.05). Compared with the group with using glycerol, the group with using glycerol had a batter conception rate, 41.3%, 54.7%, respectively.