The impacts of uterine environment and fetal genotype on conceptus size and placental vascularity during late gestation in pigs

摘要: Meishan and Yorkshire gilts were bred exclusively to boars, respectively, resulting in similar × fetuses gestating the uteri of both maternal breeds. Gilts breeds slaughtered on d 90 110 gestation, weight volume each uterine horn was determined. Fetal weights crown-rump lengths recorded. A section chorioallantoic-endometrial attachment site col- lected for conceptus evaluated placental endometrial vascular density. An intact placenta recovered weighed, its surface area crown- rump length increased ( P .20) conceptuses gestation. Additionally, even though ratio fetal weight:placental (placental efficiency) between 110, efficiency uteri. In a previous study using straightbred or gestated either uterus, we found had markedly greater than did conceptuses, regardless type uterus which they gestated. These data indicate that determines size genotype controls efficiency.