Читать книгу Parasitology - Alan Gunn - Страница 85

Commonly known as the Coccidia, this is the largest group of the Apicomplexa. All members are intracellular parasites of vertebrates and invertebrates. They usually parasitize the intestinal cells although other cell types may also be infected. Some species have only a single host, whilst others employ two – commonly a vertebrate and an invertebrate, although it may be two vertebrates, one of which feeds on the other. The life cycle usually begins with the invasion of a host cell by a sporozoite stage followed by a cycle of merogony, gametogony, and sporogony. The group used to contain just the Eimeria, the Isospora group, and the haemogregarines (mainly parasites of red blood cells of amphibians and reptiles) but currently includes Cryptosporidium, Sarcocystis, and Toxoplasma.