| Recently some protocols were developed that precisely synchronizes the time of estrus and ovulation in cattle. Those protocols mainly care about the control of follicular wave and corpus luteum (CL) development, induceing the existed follicular waves to turnover and a new wave emerge. However, in sheep and goats, few studies have been conducted taking this concept into considerations, especially in our country. In this paper, in the guide of "follicular wave " concept, experiments were carried out to optimize the effect of synchronization of estrus, superovulation and embryo transfer, and evaluate the effect of reproduction control by different horme treatments.Three experiments was conducted. The first experiment, the efficiency of the long-term treatment and short-term treatment of levonorgestrel (P4) sponges for synchronising oestrus in goats was evaluated during breeding season. Twenty indigenous goats, which were primed with two doses of Cloprostenol,lld apart, were assigned to two treatments of P4 sponges: intravaginal progestagen was administered for a 13-day period (long-term treatment group, n=10), and for a 5-day period (short-term treatment group, n=10) , at the same time of P4 treatment lOmg progesterone and Estradioli Benzoatts were muscular injected. At sponge withdrawal goats were treated with a dose of Cloprostenol. Following the termination of progestagen treatment all the does were observed for signs of oestrus with the bucks at 4h for a period of 5 days. The long-term and short-term P4 treatments did not show significant differences in estrous response (100% vs 100%) and duration (33.90?.67h VS 32.70?.43 h, P>0.05) of the induced estrous period. But time to the onset of estrus is significantly different between the two treatment (56.80?.58h VS 45.60?.85 h, P<0.01). Through observation on the ovary, the ovarian follicles ovulated, then new corpus luteum (CL) emerged in short-term P4 treatment. However, there were few persisted follicles and no ovulation and no new CL in some part of goats (40%) of long-term P4 treatment. Results indicated that the 5-day P4+EB treatment can induce better synchronization of estrus and fine ovarian response.The second experiment, the superovulatory effects of two different superovulatory method and two different P4 prime were studied. 16 indigenous goats were divided into four equalgroups: A), long-term P4 prime(13-d period), 325IU FSH dissolved in physiological saline soluion, 8 doses i.m.12h apart beginning on 1 Id morning (L-F8, n=4); B). Long-term treatment, 325IU FSH dissolved in 0.3g/ml polyvinylpyrrolidone (PVP), a single dose i.m. on lid (L-F1); C). short-term P4 prime(7-d period), F8 beginning on 5d (S-F8); D).short-term P4 prime, Fl on 5d.(S-Fl).The difference of superovulatory response, recovery of total and viable embryos between Fl and F8 treatments are not significant whether in the long-term prime (26vs26, 5 ?2.94 vs3.5?.11, 3?.56vs2.75?.40 , P>0.10) or short-term prime groups (47vs47, 9.75?0.96vslO?.83 , 7.75?.50vs9?.41,P>0.10). But the difference of superovulatory response, recovery of total and viable embryos between long-term prime and short-term groups are not significant whether in F8 groups or (26vs47, 5 ?.94 vs9.75?.96, 3 ?3.56vs7.75 ?0.50,P<0.01) in Fl groups (26vs47, 3.5 + 3.11 vslO?.83, 2.75?.40vs9?.41, P<0.01). These results showed that short-term (7-d) P4 prime can improve superovulation response , and the single injection with FSH dissolved in PVP can acquired as much viable embryos as multi-injects and makes superovulation program simpler.The third experiment, the effect of self-appointed embryo transfer program was studied. Estrous was attained by hormone treatment with two doses lid apart PG. P4 sponge were inserted and EB injected i.m. on estrous day (dO), 8d later sponge withdrawal, self-appointed fertilization is on dl0-dll. Embryos were recovered from oviduct (dl3~dl4) or from uterine horn (dl6~dl7) . The self-appointed embryo transfer program succeeded.These findings indicated that: 1) P4 wi...
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