Antibodies to Toxoplasma gondii in slaughtered free-range and broiler chickens.

The consumption of undercooked infected chicken can be a source of infection for humans and carnivores regarding the zoonotic protozoan parasite Toxoplasma gondii. Furthermore, free-range chickens are sentinels for the presence of T. gondii oocysts in the environment because they feed from the ground. By using the modified agglutination test (MAT), we investigated the presence of antibodies to T. gondii in 178 free-range and 170 broiler chickens raised indoors and slaughtered in Portugal. Prevalence of specific antibodies was 5.6% in free-range and 0.0% in broiler chickens raised indoors (p =  0.002).