Serial IgG antibody titers to Toxoplasma gondii from three juvenile great grey kangaroos (Macropus giganteus giganteus) with clinical signs consistent with toxoplasmosis were compared with titers from three clinically normal juveniles of similar age. The modified agglutination test was used to measure antibodies to T. gondii. Results demonstrated declining antibody titers to T. gondii in five of six animals. Antibody titers were similar in animals with and without clinical signs. This was interpreted as an indication that maternal IgG antibodies to T. gondii were transferred to juveniles, presumably in milk, rather than an indication of clinical disease. Therefore, clinicians should interpret Toxoplamsma serology results in juvenile macropods cautiously.