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Coccidia
Coccidia (Coccidiasina) are a subclass of microscopic, spore-forming, single-celled obligate intracellular parasites belonging to the apicomplexan class Conoidasida. As obligate intracellular parasites, they must live and reproduce within an animal cell. Coccidian parasites infect the intestinal tracts of animals, and are the largest group of apicomplexan protozoa. Infection with these parasites is known as coccidiosis. Coccidia can infect all mammals, some birds, some fish, some reptiles, and some amphibians. Most species of coccidia are species-specific in their host. An exception is '' Toxoplasma gondii'', which can infect all mammals, although it can only undergo sexual reproduction in cats. Depending on the species of coccidia, infection can cause fever, vomiting, diarrhea, muscle pain, and nervous system effects and changes to behavior, and may lead to death. Healthy adults may recover without medication—but those who are immunocompromised or young almost certainly requ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apicomplexa
The Apicomplexa (also called Apicomplexia) are a large phylum of parasitic alveolates. Most of them possess a unique form of organelle that comprises a type of non-photosynthetic plastid called an apicoplast, and an apical complex structure. The organelle is an adaptation that the apicomplexan applies in penetration of a host cell. The Apicomplexa are unicellular and spore-forming. All species are obligate endoparasites of animals, except ''Nephromyces'', a symbiont in marine animals, originally classified as a chytrid fungus. Motile structures such as flagella or pseudopods are present only in certain gamete stages. The Apicomplexa are a diverse group that includes organisms such as the coccidia, gregarines, piroplasms, haemogregarines, and plasmodia. Diseases caused by Apicomplexa include: * Babesiosis (''Babesia'') * Malaria ('' Plasmodium'') * Cryptosporidiosis (''Cryptosporidium parvum'') * Cyclosporiasis (''Cyclospora cayetanensis'') * Cystoisosporiasis (''Cystoiso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccidiosis
Coccidiosis is a parasitic disease of the intestinal tract of animals caused by coccidian protozoa. The disease spreads from one animal to another by contact with infected feces or ingestion of infected tissue. Diarrhea, which may become bloody in severe cases, is the primary symptom. Most animals infected with coccidia are asymptomatic, but young or immunocompromised animals may suffer severe symptoms and death. While coccidia can infect a wide variety of animals, including humans, birds, and livestock, they are usually species-specific. One well-known exception is toxoplasmosis caused by '' Toxoplasma gondii''. Humans may first encounter coccidia when they acquire a dog, cat or bird that is infected. Other than ''T. gondii'', the infectious organisms are canine and feline-specific and are not contagious to humans, unlike the zoonotic diseases. Coccidia in dogs Puppies are frequently infected with coccidia from the feces of their mother, and are more likely to develop coccidio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarcocystis
''Sarcocystis'' is a genus of protozoan parasites, with many species infecting mammals, reptiles and birds. Its name is dervived from Greek ''sarx'' = flesh and ''kystis'' = bladder. The lifecycle of a typical member of this genus involves two host species, a definitive host and an intermediate host. Often, the definitive host is a predator and the intermediate host is its prey. The parasite reproduces sexually in the gut of the definitive host, is passed with the feces, and ingested by the intermediate host. There, it eventually enters muscle tissue. When the intermediate host is eaten by the definitive host, the cycle is completed. The definitive host usually does not show any symptoms of infection, but the intermediate host does. About 130 recognized species are in this genus. Revision of the taxonomy of the genus is ongoing, and all the currently recognised species may be a much smaller number of species that can infect multiple hosts. History The organism was first recog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eucoccidiorida
The Eucoccidiorida are an order of microscopic, spore-forming, single-celled parasites belonging to the apicomplexan class Conoidasida. Protozoans of this order include parasites of humans, and both domesticated and wild animals including birds. Among these parasites are the '' Toxoplasma gondii'' that cause toxoplasmosis and '' Isospora belli'', which results in isosporiasis. Definition This is the largest order in the class Conoidasida and contains those species that all undergo merogony (asexual), gametogony (sexual) and sporogony (spore formation) during their lifecycles. Genera Nineteen families, three subfamilies, and 70 genera are recognised in this order. The genera include: '' Adelea'', '' Adelina'', '' Aggregata'', '' Alveocystis'', ''Atoxoplasma'', ''Babesiosoma'', '' Barrouxia'', ''Bartazoon'', ''Besnoitia'', '' Calyptospora'', '' Caryospora'', ''Caryotropha'', ''Chagasella'', ''Choleoeimeria'', ''Cryptosporidium'', ''Crystallospora'', ''Cyclospora'', ''Cyrilia'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adeleorina
''Adeleorina'' is a suborder of parasites in the phylum Apicomplexa. History Léger proposed this taxon in 1911. The first species identified was '' Dactylosoma ranarum'' by Lankester (1871) in a frog in Europe. It was initially called ''Undulina ranarum'', but this was changed in 1882 to ''Drepanidium ranarum''. This species was subsequently moved to the genus ''Dactylosoma''. Canine hepatozoonosis was first described in India in 1905 by James. The organism was named ''Leukocytozoon canis''. The vector was identified in 1907 by Christopher to be the brown dog tick ('' Rhipicephalus sanguineus''). The genus ''Hepatozoon'' was created by Miller in 1908 for a parasite of the white rat ('' Rattus norvegicus'') that underwent merogony in the liver and sporogony in the mite '' Laelap echidinus''. Ledger initially placed this genus in the family Haemogregarinidae, but Wenyon subsequently removed it and placed it in the newly created taxon Hepatozoidae in 1926. Life cycle All speci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apicomplexan Life Cycle
Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism is typified by a ''cellular variety'' with a distinct morphology and biochemistry. Not all apicomplexa develop all the following cellular varieties and division methods. This presentation is intended as an outline of a hypothetical generalised apicomplexan organism. Methods of asexual replication Apicomplexans (sporozoans) replicate via ways of multiple fission (also known as schizogony). These ways include , and , although the latter is sometimes referred to as schizogony, despite its general meaning. Merogony is an asexually reproductive process of apicomplexa. After infecting a host cell, a trophozoite ( see glossary below) increases in size while repeatedly replicating its nucleus and other organelles. During this process, the org ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oocyst
Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism is typified by a ''cellular variety'' with a distinct morphology and biochemistry. Not all apicomplexa develop all the following cellular varieties and division methods. This presentation is intended as an outline of a hypothetical generalised apicomplexan organism. Methods of asexual replication Apicomplexans (sporozoans) replicate via ways of multiple fission (also known as schizogony). These ways include , and , although the latter is sometimes referred to as schizogony, despite its general meaning. Merogony is an asexually reproductive process of apicomplexa. After infecting a host cell, a trophozoite ( see glossary below) increases in size while repeatedly replicating its nucleus and other organelles. During this process, the orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxoplasma
''Toxoplasma gondii'' () is an obligate intracellular parasitic protozoan (specifically an apicomplexan) that causes toxoplasmosis. Found worldwide, ''T. gondii'' is capable of infecting virtually all warm-blooded animals, but felids, such as domestic cats, are the only known definitive hosts in which the parasite may undergo sexual reproduction. ''T. gondii'' has been shown to alter the behavior of infected rodents in ways that increase the rodents' chances of being preyed upon by felids. Support for this "manipulation hypothesis" stems from studies showing that ''T. gondii''-infected rats have a decreased aversion to cat urine. Because cats are the only hosts within which ''T. gondii'' can sexually reproduce to complete and begin its lifecycle, such behavioral manipulations are thought to be evolutionary adaptations that increase the parasite's reproductive success. Rats that do not avoid cat habitations will more likely become cat prey. ''Toxoplasma gondii'' infection ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eimeriorina
Eimeriorina is a suborder of phylum Apicomplexa. All species in this clade are homoxenous or facultatively homoxenous. Merogony, gamogony and oocyst formation all occur within the same host. The hosts may be vertebrates or invertebrates. Erroneous identifications of species is a major problem in coccidian systematics and it is likely that some of the genera and species will be revised. Taxonomy There are 12 families, 2 subfamilies and 50 genera recognised in this suborder. The genus ''Eimeria'' with ~1500 species is the largest genus in this suborder. Notes One genus is entirely entomoxenous (parasitic on insects) — '' Barrouxia''. The taxonomic status of ''Atoxoplasma ''Atoxoplasma'' is a genus of parasitic alveolates in the phylum Apicomplexa. The species in this genus infect birds. They are spread by the orofaecal route. History This genus was created by Garnham in 1950. The history of this genus has been ...'' remains unclear. References Conoidasida SAR ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxoplasma
''Toxoplasma gondii'' () is an obligate intracellular parasitic protozoan (specifically an apicomplexan) that causes toxoplasmosis. Found worldwide, ''T. gondii'' is capable of infecting virtually all warm-blooded animals, but felids, such as domestic cats, are the only known definitive hosts in which the parasite may undergo sexual reproduction. ''T. gondii'' has been shown to alter the behavior of infected rodents in ways that increase the rodents' chances of being preyed upon by felids. Support for this "manipulation hypothesis" stems from studies showing that ''T. gondii''-infected rats have a decreased aversion to cat urine. Because cats are the only hosts within which ''T. gondii'' can sexually reproduce to complete and begin its lifecycle, such behavioral manipulations are thought to be evolutionary adaptations that increase the parasite's reproductive success. Rats that do not avoid cat habitations will more likely become cat prey. ''Toxoplasma gondii'' infection ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conoidasida
Conoidasida is a class of parasitic alveolates in the phylum Apicomplexa. The class was defined in 1988 by Levine and contains two subclasses – the coccidia and the gregarines. All members of this class have a complete, hollow, truncated conoid. Gregarines tend to parasitize invertebrates with the mature gamonts being extracellular, the coccidia mostly infect vertebrates and have intracellular gamonts. Description A conoid is found in most species and when present forms complete but truncated cone. Sexual and asexual reproduction are present in life cycle of all species. Each zygote normally forms an oocyst wall within which it undergoes meiosis. This is sometimes followed by mitosis. This process of sporogony produces mobile vermiform infectious sporozoites. Multiple mitotic divisions ( schizogony) also occur during merogony Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxoplasma Gondii
''Toxoplasma gondii'' () is an obligate intracellular parasitic protozoan (specifically an apicomplexan) that causes toxoplasmosis. Found worldwide, ''T. gondii'' is capable of infecting virtually all warm-blooded animals, but felids, such as domestic cats, are the only known definitive hosts in which the parasite may undergo sexual reproduction. ''T. gondii'' has been shown to alter the behavior of infected rodents in ways that increase the rodents' chances of being preyed upon by felids. Support for this "manipulation hypothesis" stems from studies showing that ''T. gondii''-infected rats have a decreased aversion to cat urine. Because cats are the only hosts within which ''T. gondii'' can sexually reproduce to complete and begin its lifecycle, such behavioral manipulations are thought to be evolutionary adaptations that increase the parasite's reproductive success. Rats that do not avoid cat habitations will more likely become cat prey. ''Toxoplasma gondii'' infection ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
