Fatal acute toxoplasmosis in three golden lion tamarins (Leontopithecus rosalia)

Fatal acute toxoplasmosis was diagnosed in three golden lion tamarins (Leontopithecus rosalia), a breeding pair and their male offspring, by histology and immunohistochemistry. The distribution and severity of lesions differed among the animals, but the small intestine and the pancreaticoduodenal lymph nodes were especially affected. Protozoal organisms consistent with Toxoplasma gondii tachyzoites, often clustered, were seen in all lesions and were specifically immunostained with a T. gondii polyclonal antibody. The infection was probably acquired orally. Several breeding groups of golden lion tamarins have succumbed to toxoplasmosis both in North American and European zoos, so this disease should be considered an important problem in this endangered species. Toxoplasma gondii can cause latent infections in New World primates and therefore could potentially induce abortions or congenital infections in wild golden lion tamarins born from latently infected reintroduced females.