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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Animal Parasitic Diseases Laboratory » Research » Publications at this Location » Publication #307567

Title: Sarcocystosis in a stillborn lamb

item AGERHOLM, JORGEN - University Of Copenhagen
item Dubey, Jitender

Submitted to: Reproduction in Domestic Animals
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/16/2014
Publication Date: 9/15/2014
Citation: Agerholm, J., Dubey, J.P. 2014. Sarcocystosis in a stillborn lamb. Reproduction of Domestic Animals. DOI: 10.1111/rda.12398.

Interpretive Summary: Toxoplasmosis continues to be a major public health problem in the US. The single celled parasite, Toxoplasma gondii, causes abortion in livestock and mental retardation in children. It would be important to know which related parasites are also causes of congenital disease in humans or in animals. Diagnosis of toxoplasmosis abortion in sheep, for example, is difficult and requires several diagnostic procedures because several other closely related parasites also can cause abortion. Species of Sarcocystis are protozoa that can be easily confused with Toxoplasma. In the course of investigating a suspected case of congenital toxoplasmosis in sheep, we identified a case of acute sarcocystosis in a lamb that was misdiagnosed as toxoplasmosis. These findings indicate that a species of Sarcoycystis, probably S. tenella, can induce severe congenital infections in sheep. This finding will be of interest to veterinarians and parasitologists.

Technical Abstract: Confirmed congenital sarcocystosis has not been reported in sheep and extremely rarely in other domestic ruminants. Sarcocystosis was diagnosed in a stillborn lamb with microscopic lesions predominantly in the central nervous system and placenta. Encephalitis was characterized by multiple foci of glial nodule some with central necrosis, perivasular cuffing, and vascular occlusion, while placental lesions consisted of multifocal necroses, inflammation, mild calcification. Immature and mature schizonts were found in vascular endothelium of several organs. This is the first reported case of congenital sarcocystosis in sheep. It is suggested that the protozoa was Sarcocystis tenella as this is the most pathogenic Sarcocystis sp. parasitizing sheep.