Programação da receptividade uterina e fertilidade em vacas de corte

In beef cattle, there is significant embryonic mortality during the three initial weeks of pregnancy. During this period, the development from zygote to conceptus depends exclusively on secretions from the oviduct and uterus. The process of secretion as well as the quality of such secretions are programmed by the sequential exposure of the reproductive tract to estradiol (E2), during proestrus and estrus, and to progesterone (P4), during early diestrus. Strategies that aim to optimize the quality of the oviductal and the uterine environments towards embryo development are discussed. Strategies include managing growth of the pre-ovulatory follicle, E2 supplementation at proestrus, P4 supplementation during early diestrus and combinations. Last but not least, we discuss the intriguing possibility of bovine embryo programming endometrial function as early as the first week of gestation.