Serial ultrasound examinations of the gravid uterus of a Jenny donkey (Equus asinus) carrying a transferred extraspecies horse (Equus caballus) conceptus between 11 and 33 days of gestation demonstrated that the embryo died before Day 33 even though the conceptus persisted in the uterus and the horse chorionic girdle invaded the maternal endometrium to form a circle of typically large horse endometrial cups in the right uterine horn. The high concentrations of horse CG secreted by these cups with its higher than usual ratio of FSH-like to LH-like biological activities of 1.4 compared to the 0.1 ratio of normal donkey CG hyper-stimulated the donkey’s ovaries to develop multiple large accessory follicles and resulting secondary corpora lutea which secreted high concentrations of progestagens that persisted in her bloodstream for the next 90 days. This case illustrated that, in all likelihood, girdle invasion can happen after the death of the embryo indicating autonomy of the chorionic girdle.

中文翻译：

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珍妮驴（Equus asinus）子宫内膜杯的胎儿死亡后发育

珍妮驴（Equus asinus）的妊娠子宫系列超声检查携带一匹转移的异种马（Equus caballus ）) 妊娠 11 至 33 天之间的胎盘表明胚胎在第 33 天之前死亡，即使胎盘在子宫中持续存在并且马绒毛膜带侵入母体子宫内膜在右子宫角形成一个典型的大马子宫内膜杯圈。这些杯子分泌的高浓度马 CG 与正常驴 CG 的 0.1 比率相比，其 FSH 样与 LH 样生物活性的比率高于通常的 1.4 比率，从而过度刺激了驴的卵巢发育多个大的辅助卵泡和由此产生的次级黄体分泌高浓度的孕激素，并在接下来的 90 天内持续存在于她的血液中。这个案例说明，十有八九，