Epizootics of ovine abortion due to Toxoplasma gondii in north central United States.

Toxoplasma-induced abortions were diagnosed in 14 flocks of sheep, 4 in Minnesota, 2 in Iowa, and 8 in South Dakota, during the 1982-1983 lambing season. Toxoplasma gondii was seen in histologic sections from 6 placentas and from brains of 2 lambs. Toxoplasma antibody was found by dye test and agglutination test in thoracic fluid of 15 fetal lambs. Lesions typical of toxoplasmosis were seen in fetal placentas from 26 ewes.