title: Enzootic abortion of ewes in Nigeria: an investigation into the naturally occurring disease in a research animal facility.
mesh_terms: D000034:Abortion, Veterinary / Q000453:epidemiology* / Q000382:microbiology; D000818:Animals; D004196:Disease Outbreaks; D005260:Female; D009549:Nigeria; D011247:Pregnancy; D012756:Sheep; D012757:Sheep Diseases / Q000453:epidemiology* / Q000382:microbiology