ABSTRACT
The species of Cryptosporidium infecting fish are C. molnari and C. scophthalmi. Merogonial and gamogonial stages of both species were in the typical extracytoplasmic position, whereas sporogonial stages were deep within the epithelium, with mature oocysts in parasitophorous vacuoles. Cryptosporidium molnari was described from two teleost fish, the gilthead sea bream and the European sea bass. Reports on amphibian cryptosporidiosis are scant, and there are no valid species of Cryptosporidium described from amphibians. Feces collected from Ceratophrys ornata at the Metropolitan Toronto Zoo were stained by modified Ziehl-Neelsen stain and revealed Cryptosporidium oocysts. One group of investigators reported experimental infection of amphibians with C. parvum oocysts of human origin, whereas another group was unable to infect African clawed frogs or poison dart frogs with C. parvum oocysts, which were infectious for suckling mice.
