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(invertebrate zoology)
A subclass of protozoans in the class Telosporea; typically intracellular parasites of epithelial tissue in vertebrates and invertebrates.



an order of one-celled animals of the class Sporozoa. There are approximately 1,000 species. They are intracellular parasites of the epithelial tissue primarily of the digestive organs of invertebrates (annelid worms, mollusks, and arthropods) and vertebrates. They look like small rounded cells with a bubble-shaped nucleus.

Almost every species of Coccidia parasitizes only one definite species of animal host. Most Coccidia exhibit regular alternation of asexual reproduction (schizogony), a sexual process, and sporogony. Asexual reproduction is absent only in the most primitive group—Protococcidiida (genus Eucoccidium). Spores keep the sporozoites viable outside the host’s body for several months, until the oocyst is swallowed by the animal host. The majority of species of Coccidia develop in one host. Some Coccidia have two—for example, members of the genus Aggregata undergo asexual reproduction (schizogony) in crabs and the sexual process and sporogony in gastropod mollusks. Coccidia are very widely distributed. Some cause coccidiosis.


Kheisin, E. M. Zhiznennye tsikly koktsidii domashnikh zhivotnykh. Leningrad, 1967.


References in periodicals archive ?
concinna metteri were collected alive by hand from Somervell County, Texas, and Garland County, Arkansas, respectively, and their feces examined for coccidian parasites.
Two life cycle stages of a coccidian were identified in the epithelium of the interlamellar bridges of gills, trophozoites, and magrogametocytes (Fig.
Cyclospora cayetanensis, the most recently identified coccidian, presents with similar pathologic features to Cryptosporidium and Isospora species.
parvum is a coccidian enteric pathogen of mammals that causes clinical disease in numerous species, including swine and humans (172).
cayetanensis recently has been characterized as a coccidian parasite - a one-celled organism that cannot be seen without a microscope and inhabits the mucosa of the small intestine.
Minchy, a miniature pinscher, was sold by Petland at 10 weeks and was immediately diagnosed with coccidian, an intestinal parasite that causes diarrhea and weight loss.
Ebers, College of William & Mary, "Temporal pattern of infection by an Isospora coccidian parasite of Zebra Finches.
A few of these oval bodies exhibited 4 spindle-shaped structures which were identified provisionally as merozoites of a coccidian parasite (Figure, panel C).
Surveillances for coccidian oocysts of feces samples were carried out from 7 to 11 days of post- challenged.
Coccidian parasites in the genera Isospora and Eimeria are common in vertebrate hosts.
The chapter "Isospora, Atoxoplasma, and Sarcocystis'" would fit better directly adjacent to the other chapters on coccidian parasites, that is, with the chapters titled "Eimeria" and "Disseminated Visceral Coccidiosis in Cranes.