Fetal mummification due to Neospora caninum in an Angus cow

Abstract

A mature Angus cow was presented to the Purdue University Veterinary Teaching Hospital for a suspected abortion. The owner noticed that the cow had placenta hanging from her vulva but was showing no signs of active labor. The cow was palpated per rectum by the owner and a hard structure was palpated in the vaginal vault. The cow was from a 35 head beef herd that has had five abortions in the past two years. In the present year, the herd has experienced three abortions in addition to this case. Upon presentation and physical examination, the cow was systemically healthy. Approximately 20 cm of fetal membranes was protruding from the vulva. Rectal and vaginal palpation revealed a 4cm x 3cm x 16cm hard, discoid structure within the vagina vault with a palpably empty orbit. The cow was administered a caudal epidural and a fetal mummy and associated placenta was extracted from the vagina. The fetus and placenta were submitted for necropsy and histopathology. The fetus was found to be positive for Neospora caninum by PCR testing with no other bacteria or viral organisms isolated. The dam was also found to be positive for Neospora caninum by ELISA. Neospora caninum is a major cause of abortion in both dairy and beef cattle. Cattle become infected following ingestion of the oocyst. Cows may abort from three months gestation to term with most abortions occurring at five to six months of gestation. Fetuses may also be stillborn, born alive with clinical signs or born clinically normal but persistently infected. 1,2 Mummified fetuses are not a common presentation associated with Neospora infections. This case demonstrates that in cases of mummified fetuses, Neospora caninum should be considered as a differential diagnosis. Neospora is an economically important disease world-wide affecting both the dairy and beef industries.