Pathological Findings in Equine Herpesvirus 9-Induced Abortion in Rats

• Published in: Journal of comparative pathology Vol. 151; no. 4; pp. 400 - 409
• Main Authors: El-Habashi, N., El-Nahass, E., Haridy, M., Nayel, M., Abdelaziz, A.A., Fukushi, H., Kuroda, K., Sakai, H., Yanai, T.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-11-2014
• Subjects: Abortion, Veterinary - virology; Animals; Disease Models, Animal; Equine herpesvirus; equine herpesvirus-9; Female; Fetal Death - etiology; Herpesviridae Infections - complications; Immunohistochemistry; pathogenicity; Pregnancy; rat model; Rats; Reverse Transcriptase Polymerase Chain Reaction; Varicellovirus; pathogenicity; rat model; equine herpesvirus-9; pregnancy
• ISSN: 0021-9975; 1532-3129
• DOI: 10.1016/j.jcpa.2014.08.006

Pregnant rats were infected experimentally with equine herpesvirus (EHV)-9, a new neurotropic equine herpesvirus serologically similar to EHV-1, during the first and third trimesters. The inoculated dams had mild to severe neurological signs and gave birth to dead fetuses or undersized pups. Rats inoculated during the first and last trimesters had varying degrees of encephalitis as well as abnormalities of the placentas in the form of marked dilation of maternal blood sinusoids and varying degrees of atrophy and necrosis of the trophoblast cells of the labyrinth, the spongiotrophoblasts and the giant cell layer. Virus antigen was detected by immunohistochemistry in the brain and the trophoblast cells of labyrinth, the spongiotrophoblasts and giant cell layer of the placenta in rats inoculated during the first trimester. Virus antigen was detected in fetuses from rats inoculated in the first and last trimesters. Virus DNA was amplified by polymerase chain reaction from the placenta and fetuses of inoculated rats. EHV-9 may induce fetal death and abortion in pregnant dams, possibly caused by direct EHV-9 infection of the placenta and/or fetus as well as the secondary effect of vascular injury.