This is the first report to document transplacental transmission of Anaplasma phagocytophillum in the horse. A 4‐year‐old late‐term pregnant mare presented for a recent onset of pyrexia due to equine granulocytic anaplasmosis (EGA). She was hospitalised for treatment with oxytetracycline and monitoring of high‐risk foaling due to significant thrombocytopenia. Parturition occurred overnight, and the foal was PCR positive for A. phagocytophilum at birth. The foal was slow to stand and nurse, with signs of neonatal encephalopathy and anaplasmosis (thrombocytopenia). Therapy with oxytetracycline resulted in complete clinical recovery of the mare and foal within 5 days. Congenital anaplasmosis should be considered in any foal delivered to a mare suffering from EGA during late‐term pregnancy and guide appropriate antimicrobial therapy.

中文翻译：

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小牛经胎盘感染无嗜浆细胞

这是第一份记录马经吞噬性嗜浆细胞经胎盘传播的报告。一名4岁的晚期母马因马颗粒细胞无性病（EGA）而出现近期发热。她因土霉素治疗住院，并监测了由于血小板减少症而引起的高危驹。分娩发生过夜，小马对吞噬嗜血曲霉PCR呈阳性出生时。小马驹站立和护理缓慢，有新生儿脑病和无丝虫病（血小板减少）的迹象。土霉素的治疗导致5天内母马和小马的临床症状完全恢复。在晚期妊娠期间将任何小马驹运到患有EGA的母马中，都应考虑先天性肛门炎，并指导适当的抗菌治疗。