Lawson R A, Cahill L P
J Reprod Fertil. 1983 Mar;67(2):473-5. doi: 10.1530/jrf.0.0670473.
When 25 mg progesterone/day were injected into ewes on Days 0-3 of the oestrous cycle, (i) the subsequent cycle was shortened by 4 days and (ii) on Day 6 such ewes provided an acceptable uterine environment for the survival of 10-day-old embryos. We suggest that exposure of the non-pregnant uterus to approximately 8 days of normal luteal concentrations of progesterone may be necessary to initiate luteolysis.
在发情周期的第0 - 3天，每天给母羊注射25毫克孕酮，（i）随后的周期缩短了4天，并且（ii）在第6天，这些母羊为10日龄胚胎的存活提供了适宜的子宫环境。我们认为，未孕子宫暴露于正常黄体期浓度的孕酮约8天，可能是启动黄体溶解所必需的。
