Toxoplasmosis in Goats in Riyadh, Saudi Arabia

During an outbreak of caprine abortion in a farm in Riyadh, Saudi Arabia, serum samples from 57 Aardi goats with recent history of abortion and stillbirths (herd 1) along with samples from 30 control goats without abortion history (herd 2) were analyzed for anti-Toxoplasma gondii antibodies using indirect Enzyme-Linked Immunosorbent Assay (ELISA) and Indirect Haemagglutination (IHA) tests. Antibodies against T. gondii were detected by ELISA in 63.2% of the goats in herd 1 and 50% of the control goats (herd 2). About >80% of the former goats had ELISA percent optical densities (O.D.%) >= 100 while >86% of the control goats were weakly positive with ELISA O.D.'s (%) <100. IHA tests were positive in 51.7% of herd 1 versus 30% of control goats. About 78% of all IHA positive goats in herd 1 had antibody titers ranging between 1:640-1:2560 including nearly 30% with titers ranging between 1:1280-1:2560. By contrast, all IHA positive goats in herd 2 had titers ranging only between 1:80-1:160, except one goat with a titer of 1:640 and none with higher titers. IHA tests for IgM antibodies using 2-mercaptoethanol treated sera revealed IgM antibodies in 16 (28%) goats with abortion history (herd 1) and none in control goats (herd 2). Focal pathological changes were observed in the fetal brain and the placenta of some of the aborted goats. These findings strongly suggest T. gondii as the cause of abortion in herd 1.