Toxoplasmosis, characterized by antibody titers up to 16 million, isolation of T. gondii from blood, and demonstration of cyst forms of T. gondii in the tissues of neonatal kittens, occurred in pallas cats (Felis manul) in a zoo in California. Infections were clinically inapparent, except in the kittens, which developed fatal encephalitis, pneumonitis, hepatitis, myocarditis and nephritis. A possible source of infection was feral pigeons, which once formed a major part of the cats' diet.