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Sarcocystidae
The Sarcocystidae are a family of Apicomplexa associated with a variety of diseases in humans and other animals. Taxonomy Genera in this family include: * '' Besnoitia'' * ''Cystoisospora'' * ''Frenkelia'' * ''Nephroisospora'' * '' Neospora'' * ''Sarcocystis'' * ''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 d ...'' Evolution The genera ''Neospora'' and ''Toxoplasma'' appear to have diverged about . References External links Overview at webends.com* Genes Apicomplexa families {{Apicomplexa-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyaloklossia
''Hyaloklossia'' is a genus of parasitic alveolates in the phylum Apicomplexa. Only one species in this genus is currently recognised - ''Hyaloklossia lieberkuehni''. History This parasites of this genus was first observed by Lieberkuhn in 1854 within the renal cortex of a frog of the genus ''Rana''. Labbe in 1894 initially named this species ''Klossia lieberkuehni''. Labbe in 1896 moved this species to a new genus ''Hyaloklossia''. Laveran and Mesnil in 1902 and Minchin in 1903 moved this species into the genus ''Diplospora'' Labbe 1893. It was moved again into the genus ''Isospora'' by Noller in 1923. The species was replaced in the genus ''Hyaloklossia'' by Modry ''et al.'' in 2001. Description There are two sporocysts within the ocysts. The oocysts have a thin, elastic, relatively fragile wall. The sporocysts are tetrazoic. The sporocyst wall is composed of plates joined by sutures and Stieda and substieda bodies are absent. The life cycle is homoxenous. Endogenou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frenkelia
''Frenkelia'' is a genus of parasites in the phylum Apicomplexa. The species in this genus infect the gastrointestinal tracts of birds of prey (definitive hosts) and the tissues of small rodents (intermediate hosts). Taxonomy Species of this genus share antigens with ''Sarcocystis''. DNA studies suggest that this genus should be merged with ''Sarcocystis''. Despite several recommendations, abolition of this genus has not yet been approved. Lifecycle The parasites undergo sexual reproduction in the gut of the definitive host — a bird of prey. They form cysts and are then eaten by a small rodent. Within the gut of the rodent, the parasites decyst. They invade the intestinal wall and are carried to the liver. They undergo schizogony in the hepatocytes and Kupffer cells. They then invade the nervous tissue of the rodent host, forming cystic structures. The infected rodent is then eaten by a bird, when the tissue cysts are digested, releasing the parasites. The parasites invad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cystoisospora
''Cystoisospora'' is a genus of parasitic alveolates belonging to the phylum Apicomplexa. Taxonomy This genus was originally created by J. K. Frenkel in 1977. Its use was discontinued but was resurrected in 2005. This genus currently includes species that have oocysts containing two sporocysts with four sporozoites in each without Stieda bodies. These species infect the enterocytes of mammals and are transmitted by the orofaecal route. DNA analysis has shown that this genus belongs to the family ''Sarcocystidae''. The type species of this genus is ''Cystoisospora felis''. Life cycle This parasite has been isolated from dogs, cats and raccoons. ''C. belli'' has been isolated from immunosuppressed humans — particularly those with HIV infection. These parasites normally infect the enterocytes of the small intestine and are spread by the orofaecal route. The definitive hosts are cats but other species including various species of rodents may be infected. No further developme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hammondia
''Hammondia'' is a genus of parasitic alveolates in the phylum Apicomplexa. History This genus was created in 1975. Before this date the species of this genus were confused with ''Toxoplasma gondii'' to which they are closely related. The canid Canidae (; from Latin, ''canis'', "dog") is a biological family of dog-like carnivorans, colloquially referred to as dogs, and constitutes a clade. A member of this family is also called a canid (). There are three subfamilies found within the ...-infecting species, ''H. heydorni'' and ''H. triffittae'', have been split into new genus '' Heydornia'' based on the molecular phylogenetic analysis. Life cycle The species in this genus have two vertebrate hosts in their life cycle: a felid (the definitive host) and prey species (the intermediate host), which vary and depend on the local fauna but include mice, deer and others. In the gastrointestinal tract of the definitive host the parasite undergoes sexual reproduction, forms a zygo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nephroisospora
''Nephroisospora'' is a genus of parasites that infects bats History This genus was described in 2010 by Wünschmann ''et al''. Taxonomy There is one recognised species in this genus — ''Nephroisospora eptesici''. Description This genus infects the kidneys of brown bats (''Eptesicus fuscus''). The host reaction is usually generally mild, focal or multifocal and consists of well demarcated cortical renal lesion less than 1 millimeter in diameter. Histologically these lesions are cystic, dilated tubules with hypertrophied tubular epithelial cells. The protozoa develop in the tubular epithelial cells and within the lumen of the cysts that develop as a response to infection. The oocysts are thin walled, sporulated and ellipsoidal measuring an average of 18.9 x 20.8 micrometers. Each oocysts contains 2 sporocysts with 4 sporozoite Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are ... [...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] |
Besnoitia Besnoiti
''Besnoitia besnoiti'' is an apicomplexan protozoan parasite, closely related to ''Toxoplasma gondii'' and ''Neospora caninum,''''.'' It is part of a larger genus '' Besnoiti'' affecting multiple animal species, but ''Besnoita besnoiti, can affect livestock. and more'' specifically cattle as intermediate host, although some specific antibodies have been found in roe deer and red deer. The biological cycle of the parasite remains unknown, it is suggested however that a carnivore, or more specifically the red fox, might be the definitive host In biology and medicine, a host is a larger organism that harbours a smaller organism; whether a parasitic, a mutualistic, or a commensalist ''guest'' (symbiont). The guest is typically provided with nourishment and shelter. Examples include a .... Geographical area The origin of the disease seems to be difficult to specify, as there has been little attention to it until the end of the 20th century. It seems to be endemic from south o ... [...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 i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tachyzoite
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 or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Besnoitia
''Besnoitia'' is a genus of apicomplexan parasites. Life cycle The life cycle of many of the species in this genus are not known. The life cycle may be complex with various intermediate hosts and vectors including ''Stomoxys'' and ''Tabanidae Horse-flies or horseflies are true flies in the family Tabanidae in the insect order Diptera. They are often large and agile in flight, and only the female horseflies bite animals, including humans, to obtain blood. They prefer to fly in s ...''. Pathology and effects on the host Infection with these parasites causes pedunculated lesions in the skin, nasal cavity and larynx of domestic animals. The lesions consist of exophytic nodules protruding from mucosal surfaces. See also * Besnoitiosis References Apicomplexa genera Conoidasida {{Apicomplexa-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neospora
''Neospora'' is a single celled parasite of livestock and companion animals. It was not discovered until 1984 in Norway, where it was found in dogs. Neosporosis, the disease that affects cattle and companion animals, has a worldwide distribution. ''Neosporosis'' causes abortions in cattle and paralysis in companion animals. It is highly transmissible and some herds can have up to a 90% prevalence. Up to 33% of pregnancies can result in aborted fetuses on one dairy farm. In many countries this organism is the main cause of abortion in cattle. Neosporosis is now considered as a major cause of abortion in cattle worldwide. Many reliable diagnostic tests are commercially available. ''Neospora caninum'' does not appear to be infectious to humans. In dogs, ''Neospora caninum'' can cause neurological signs, especially in congenitally infected puppies, where it can form cysts in the central nervous system. Genome The genome of ''Neospora caninum'' has been sequenced.Khan A, Fujita AW ... [...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 i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
