Serologic and histologic diagnosis of toxoplasmic abortions in sheep in Oregon.

Between 1983 and 1989, we examined 586 fetuses and dead lambs submitted to a diagnostic laboratory in Oregon. Toxoplasmosis was diagnosed in 74 (12.6%), campylobacteriosis in 89 (15.2%), chlamydiosis in 75 (12.8%), miscellaneous infections in 153 (26.1%), noninfectious causes in 37 (6.3%), and undetermined causes in 158 (27.0%). Detection of Toxoplasma gondii agglutinating antibodies (greater than or equal to 20) in body fluids or heart serum was considered specific for the diagnosis of toxoplasmosis in ovine fetuses or lambs. Toxoplasma gondii antibody titers (reciprocal) in 285 fluids from fetuses or dead lambs were less than 20 (64.5%), 20 (4.5%), 40 (1.7%), 80 (0.7%), 160 (2.1%), 320 (1.7%), 640 (4.9%), 1,280 (2.8%), 2,560 (4.5%), 5,120 (3.8%), 10,240 (2.1%), and greater than or equal to 20,480 (6.3%).