[Development of Eimeria tenella in a nonspecific host: the mouse]

The existence of extra-intestinal stages of a chick coccidium, Eimeria tenella, has been demonstrated in a non-specific host, the mouse. Between 1 and 14 days after inoculation the lungs and blood of mice were periodically infective for chicks. This is consistent with parasite development, rather than survival in the lungs and passage of free elements by the bloodstream. This type of development with extra-intestinal stages in a non-specific host has certain analogies with a related genus Toxoplasma. The type of development remains to be demonstrated.