Toxoplasmosis is one of the most prevalent parasitic infections of man and livestock, and its transmission has usually been attributed to ingestion of undercooked or raw meat from infected livestock, with the infection rate in those animals being an important risk predictor of human disease, high in Iran and Ardabil State. During a study on this public health problem, we tested serum samples from cattle, goats, sheep and chicken from the State of Ardabil, Iran, for IgG antibodies to Toxoplasma gondii
by enzyme-linked immunosorbent assay (ELISA). Antibodies to Toxoplasma gondii
were found in 30% (60/200) of sheep, 15% (30/200) of goats and 9% (18/200) of cattle, and none were found in chicken sera. Despite the differences in feeding habits of each species, the rate of infection of the animals tested could be attributed to livestock management methods, whose improvement could reduce infection.