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Ascarid
The Ascarididae are a family of the large intestinal nematoda, roundworms. Members of the family are intestinal parasites, infecting all class (biology), classes of vertebrates. It includes a number of genus, genera,Anderson RC (2000)''Nematode Parasites of Vertebrates. Their Development and Transmission, 2nd ed.''CAB International, Wallingford, Oxon, UK, pp. 245-315. the most well known of which are: *''Amplicaecum'' *''Angusticaecum'' *''Ascaris'' *†''Ascarites'' (fossil)Poinar Jr, G. and Boucot, A. J. (2006) Evidence of intestinal parasites of dinosaurs. ''Parasitology'', 133: 245-249. *''Baylisascaris'' *''Crossophorus'' *''Dujardinascaris'' *''Hexametra'' *''Lagochilascaris'' *''Ophidascaris'' *''Parascaris'' *''Polydelphis'' *''Seuratascaris'' *''Toxascaris'' *''Toxocara'' *''Travassoascaris'' ''Ascaris lumbricoides'' is the main ascarid parasite of humans, causing ascariasis. References External links ZipcodeZoo [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxocara Cati
''Toxocara cati'', also known as the feline roundworm, is a parasite of cats and other felids. It is one of the most common nematodes of cats, infecting both wild and domestic felids worldwide. Adult worms are localised in the gut of the host. In adult cats, the infection – which is called toxocariasis – is usually asymptomatic. However, massive infection in juvenile cats can be fatal. Feline roundworms are brownish-yellow to cream-colored to pink and may be up to 10 cm in length. Adults have short, wide cervical alae giving their anterior ends the distinct appearance of an arrow (hence their name, ''toxo'', meaning arrow, and ''cara,'' meaning head). Eggs are pitted ovals with a width of 65 μm and a length of about 75 μm making them invisible to the human eye. The larvae are so small that they are easily transmitted from an adult female to her nursing kittens through her milk. Transmission Wild felids can become infected from a variety of sources; the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascariasis
Ascariasis is a disease caused by the parasitic roundworm ''Ascaris lumbricoides''. Infections have no symptoms in more than 85% of cases, especially if the number of worms is small. Symptoms increase with the number of worms present and may include shortness of breath and fever at the beginning of the disease. These may be followed by symptoms of abdominal swelling, abdominal pain, and diarrhea. Children are most commonly affected, and in this age group the infection may also cause poor weight gain, malnutrition, and learning problems. Infection occurs by ingesting food or drink contaminated with ''Ascaris'' eggs from feces. The eggs hatch in the intestines, the larvae burrow through the gut wall, and migrate to the lungs via the blood. There they break into the Pulmonary alveolus, alveoli and pass up the Vertebrate trachea, trachea, where they are coughed up and may be swallowed. The larvae then pass through the stomach a second time into the intestine, where they become adul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascaris
''Ascaris'' is a nematode genus of parasitic worms known as the "small intestinal roundworms". One species, ''Ascaris lumbricoides'', affects humans and causes the disease ascariasis. Another species, ''Ascaris suum'', typically infects pigs. Other ascarid genera infect other animals, such as '' Parascaris equorum'', the equine roundworm, and '' Toxocara'' and '' Toxascaris'', which infect dogs and cats. Their eggs are deposited in feces and soil. Plants with the eggs on them infect any organism that consumes them. ''A. lumbricoides'' is the largest intestinal roundworm and is the most common helminth infection of humans worldwide. Infestation can cause morbidity by compromising nutritional status, affecting cognitive processes, inducing tissue reactions such as granuloma to larval stages, and by causing intestinal obstruction, which can be fatal. Morphology and Anatomy * Adult: cylindrical shape, creamy white or pinkish in color * Male: average ; more slender than the fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxascaris
''Toxascaris leonina'' is a common parasitic roundworm found in dogs, cats, foxes, and related host species. ''T. leonina'' is an ascarid nematode, a worldwide distributed helminth parasite which is in a division of eukaryotic parasites that, unlike external parasites such as lice and fleas, live inside their host. The definitive hosts of ''T. leonina'' include canids (dogs, foxes, etc.) and felines (cats), while the intermediate hosts are usually rodents, such as mice or rats. Infection occurs in the definitive host when the animal eats an infected rodent. While ''T. leonina'' can occur in either dogs or cats, it is far more frequent in cats. A coprolite containing ''T. leonina'' eggs was excavated in Argentina's Catamarca Province and dated to 17002–16573 years old. This finding indicates that ''T. leonina'' has existed in South America since at least the Late Pleistocene. Life cycle The life cycle of ''T. leonina'' is fairly simple. Eggs are ingested and hatch in the small ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baylisascaris
''Baylisascaris'' is a genus of roundworms that infect more than fifty animal species. Life cycle ''Baylisascaris'' eggs are passed in feces and become active within a month. They can remain viable in the environment for years, withstanding heat and cold. Animals become infested either by swallowing the eggs or eating another animal infested with ''Baylisascaris.'' Disease progression After an animal swallows the eggs, the microscopic larvae hatch in the intestine and invade the intestinal wall. If they are in their definitive host they develop for several weeks, then enter the intestinal lumen, mature, mate, and produce eggs, which are carried out in the fecal stream. If the larvae are in a paratenic host, they break into the bloodstream and enter various organs, particularly the central nervous system. A great deal of damage occurs wherever the larva try to make a home. In response to the attack, the body attempts to destroy it by walling it off or killing it. The larva mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nematode Families
The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (helminths) are the cause of soil-transmitted helminthiases. They are classified along with arthropods, tardigrades and other moulting animals in the clade Ecdysozoa. Unlike the flatworms, nematodes have a tubular digestive system, with openings at both ends. Like tardigrades, they have a reduced number of Hox genes, but their sister phylum Nematomorpha has kept the ancestral protostome Hox genotype, which shows that the reduction has occurred within the nematode phylum. Nematode species can be difficult to distinguish from one another. Consequently, estimates of the number of nematode species are uncertain. A 2013 survey of animal biodiversity suggested there are over 25,000. Estimates of the total number of extant species are subject to eve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. Phylogeneti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parascaris
''Parascaris'' is a genus of nematodes in the family Ascarididae. It contains two species, ''Parascaris equorum ''Parascaris equorum'' is a species of ascarid that is the equine roundworm. Amongst horse owners, the parasites are colloquially called "Ascarids". This is a host-specific helminth intestinal parasite that can infect horses, donkeys, and ze ...'' and '' Parascaris univalens'', which are morphologically identical, but can be distinguished by chromosome number. Both species parasitize horses. References Ascaridomorpha Chromadorea genera {{nematode-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitic Nematodes Of Vertebrates
Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson characterised parasites' way of feeding as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the broomrapes. There are six major parasitic strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), trophicallytransmitted parasitism (by being eaten), vector-transmitted parasitism, parasitoidism, and micropredation. One major axis of classification concerns invasiveness: an endoparas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascaris Lumbricoides
''Ascaris lumbricoides'' is a large parasitic worm, parasitic Nematoda, roundworm of the genus ''Ascaris.'' It is the most common parasitic worm in humans. An estimated 807 million–1.2 billion people are infected with ''Ascaris lumbricoides'' worldwide. People living in tropics, tropical and subtropics, subtropical countries are at greater risk of infection. Infection by ''Ascaris lumbricoides'' is known as ascariasis. It has been proposed that ''Ascaris lumbricoides'' and ''Ascaris suum'' (pig roundworm) are the same species. Life cycle ''Ascaris lumbricoides'', a roundworm, infects humans via the fecal-oral route. Eggs released by adult females are shed in feces. Unfertilized eggs are often observed in fecal samples but never become infective. Fertilized eggs embryonate and become infectious after 18 days to several weeks in soil, depending on the environmental conditions (optimum: moist, warm, shaded soil).Parasites - Ascariasis. (14 February 2018). Retrieved from https:/ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
