Besnoitia besnoiti: studies on the definitive host and experimental infections in cattle.

Domestic cats, 11 other species of carnivorous mammals, 6 species of snakes, and white-backed vultures were tested for their possible role as definitive hosts of Benoitia besnoiti by feeding with cystic material from chronically infected bovines. None of the species tested is a definitive host; hence, the life cycle of this parasite remains obscure. In attempts to produce clinical cases of besnoitiosis by experimental infection, bovines were inoculated IV, SC, and IP with cystozoites or tachyzoites. Immunosuppression of the animals was essential for the development of severe cases and skin lesions; cystozoites proved to be more pathogenic than tachyzoites.