关键词: 形势, 形势, 增收, 机制

Abstract: Different methods was used to study the effect of the estrus and ovulation induction of sows in this paper. Three methods were applied to research the estrus and ovulation induction of sows. The results showed that the estrous rate and conception rate using PMSG+HCG method were extremely different（P﹤0.01）from those of trio-mixture hormone method, and significant difference（P﹤0.05）from those of PMSG method, and the estrous rate and conception rate of PMSG method were significant difference（P﹤0.05）from those of trio-mixture hormone method. The estrous peak of sows treated by PMSG+HCG method was 48~96 hour after injected hormone, and the estrus of sows presented the obvious synchronization. The litter size and the number of alive piglets of sows were improved by using PMSG+HCG method, but conception rate of sows weren’t influenced by this method. The observation of the ovulation and early-embryos’ development of sows showed that the quality of embryos wasn’t influenced upon when PMSG+HCG method was used to be estrus and ovulation induction of sows. The embryos began to enter womb before 60h after sows accepted mating of the boar, and they should be in 4 cell stage in this time. The results explained that the effect of gonadotropin on estrus induction of sows were better than that of sex hormone. It was feasible that the estrus and ovulation of sows were induced by injecting the appropriate dose of PMSG and HCG.