A 6‐year‐old Hereford embryo donor cow was referred to Auburn University College of Veterinary Medicine for a mass in the tip of her left uterine horn. The cow had recently undergone an embryo collection which yielded unfertilized, degenerated ova. Transrectal palpation and ultrasound revealed a multi‐locular mass enveloped by two separate compartments that resembled an amniotic and allantoic cavity within the uterus. Tissue was collected via a uterine flush and submitted for histopathology. The tissue was determined to be placenta, confirming the diagnosis of a molar pregnancy. Following treatment, the cow was able to produce numerous viable embryos. Molar pregnancies are rare and characterized by abnormal growth of trophoblastic cells leading to formation of intrauterine cystic masses. It is important to routinely perform an ultrasonographic examination of the cow's reproductive tract approximately 30 days following non‐surgical in vivo embryo collections to detect and treat unwanted conditions such as pregnancy and cystic conditions.

中文翻译：

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胚胎供体牛的磨牙妊娠。

一名6岁的赫里福德胚胎供体母牛因左子宫角尖端出现肿块而被转诊至奥本大学兽医学院。这头牛最近接受了胚胎采集，产生了未受精的变性卵。经直肠触诊和超声检查显示多房性肿块被两个独立的隔室包裹，类似于子宫内的羊膜腔和尿囊腔。通过子宫冲洗收集组织并进行组织病理学检查。确定该组织为胎盘，证实了磨牙妊娠的诊断。经过治疗，母牛能够产生许多有生命的胚胎。磨牙妊娠很少见，其特征在于滋养细胞的异常生长导致子宫内囊性肿块的形成。