|DUBEY JITENDER P|
Submitted to: Canadian Veterinary Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/28/1994
Publication Date: N/A
Interpretive Summary: Neospora is a recently recognized protozoan genus that causes abortion and neonatal mortality in cattle and other species of livestock in the United States, Europe, Africa, and Australasia. Its life cycle and source of infection are unknown. Scientists at the Beltsville Agricultural Research Center and the Atlantic Veterinary College, Prince Edward Island University in Canada report for the first time Neospora-associated abortion in cattle from Atlantic States. The report enlarges the geographic distribution of the disease.
Technical Abstract: During a 5-month period between July and November 1993, a 70-cow dairy herd experienced 5 abortions. These abortions occurred between 3 and 8 months of gestation in cows ranging from 2-6 years of age. The abortion rate was less than 5% during each of the previous 2 years. Formalin-fixed sections of heart, brain and liver from a fetus revealed microscopic changes typical lof Neospora-induced abortion. Cardiac changes included a mixed mononuclea cell infiltrate in epicardium, myocardium and endocardium plus multifocal myocardial necrosis with mild mineralization. Foci of necrosis and microgliosis were scattered throughout all areas of brain examined and were especially prominent in the brainstem. Microglial nodules in the cerebral cortex were often located adjacent to blood vessels at the interface of grey and white matter. Neither protozoal tissue cysts nor tachyzoites were observed on H&E stained sections. Immunohistochemical stains utilizing polyclonal anti-Neospora caninum antiserum demonstrated tachyzoites within brain lesions. This is the first confirmed case of Neospora-induced bovine abortion in the Maritimes.