Elaeophora

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Elaeophora is also a synonym for the plant genus Plukenetia.

Elaeophora
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Nematoda
Class: Chromadorea
Order: Rhabditida
Family: Onchocercidae
Genus: Elaeophora
Railliet & Henry 1912
Type species
Elaeophora poeli
(Vryburg 1879) Railliet and Henry 1912
Species

Elaeophora is a genus of parasitic nematodes which live attached to the interior surfaces of major arteries, veins and/or heart chambers in various large mammal hosts. Infestation with Elaeophora species is referred to as elaeophorosis. The species of Elaeophora have been found in Africa, Asia, Europe, and North America. Despite the fact that they produce aneurysms in the arteries and heart of their hosts which measure up to 2 cm in diameter, overt clinical symptoms of infestation are seldom reported, with the notable exception of E. schneideri infestation in sheep, elk, and moose. [1]

Contents

Taxonomy

The type species Elaeophora poeli was first described as Filaria poeli in 1879. In 1912, the genus Elaeophora was created to distinguish this species from the other species of the genus Filaria . [2] Elaeophora was made the senior synonym of the genera Alcefilaria and Cordophilus in 1976. [3]

Species

General life cycle

Detailed life cycle studies have been reported for only one species of Elaeophora so far - E. schneideri. Microfilariae (not eggs) are shed by the adult female from her attachment site inside the lumen of the carotid artery of the definitive host. The microfilariae are carried through the blood stream and become lodged in the small capillaries of the skin in the head and facial areas. Blood-feeding horse flies ingest the microfilariae, which develop into infective larvae in the fly. The infective larvae enter a new definitive (mammal) host through the bite wound when the fly feeds again. The infective larvae migrate to secondary arterial sites, where they mature before migrating to the carotid artery. In the carotid artery, they mature into adults and reproduce sexually to produce microfilariae. It is assumed that the life cycles of other species of Elaeophora follow this general pattern.

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Elaeophora elaphi is a nematode parasite found in the blood vessels of the liver in Red Deer in certain parts of Spain. The adult male measures 77 mm long and 549 µm wide, adult females are 91–109 mm long and 793-1049 µm wide, and microfilariae are 225 µm long. Though adult E. elaphi induce lesions in the blood vessels, and appear to activate the local immune response, they seldom cause overt clinical symptoms in their hosts.

Elaeophora poeli is a parasitic nematode found in the aorta, and sometimes the heart, of various cattle throughout Asia, and in parts of Africa. It is a large nematode, with males measuring 45–70 mm long and 200-260 µm wide, and females 40–300 mm long and 350 µm wide. Microfilariae are 340-346 µm long and 7.0-7.5 µm wide. Despite the fact that it lives in nodules (aneurysms) in the walls of the aorta and heart, apparent clinical symptoms of E. poeli infestation are seldom reported.

Elaeophora sagitta is a parasitic nematode found in the heart, coronary arteries and pulmonary arteries of several ruminant species and African buffaloes in Africa. Infestation usually occurs without significant health effects in the Greater kudu, but may affect cardiac function in some other host species.

Microfilaria

The microfilaria is an early stage in the life cycle of certain parasitic nematodes in the family Onchocercidae. In these species, the adults live in a tissue or the circulatory system of vertebrates. They release microfilariae into the bloodstream of the vertebrate host. The microfilariae are taken up by blood-feeding arthropod vectors. In the intermediate host the microfilariae develop into infective larvae that can be transmitted to a new vertebrate host.

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Sarcocystis is a genus of parasitic Apicomplexan alveolates. Species in this genus infect reptiles, birds and mammals. The name is derived from Greek: sarkos = flesh and kystis = bladder.

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<i>Onchocerca tubingensis</i> Species of roundworm

Onchocerca tubingensis is the name of a nematode. It was discovered in 1974 and published by O. Bain und H. Schulz-Key in Tropenmedizin und Parasitologie and named after Tübingen. Red deer are the host of this parasite. The adult worms of Onchocerca tubingensis are found in subcutaneous nodules on the caudal part of the back, while the microfilariae are distributed on the ventral part of the body with maximum densities in the region of the sternum and with lower densities on the inner sides of the hindlegs. The infection rates of 94 red deer investigated in southern Germany during 1907–1974 were 23%.

<i>Dermacentor albipictus</i>

Dermacentor albipictus, the winter tick, is a species of hard tick that parasitizes many different mammal species in North America. It is commonly associated with cervid species such as elk, white-tailed deer and mule deer and caribou but is primarily known as a serious pest for moose ." As early as 1909, Ernest Thompson Seton described the winter tick as a greater enemy of the moose than were "wolves, bears, and cougars."

References

  1. Pence, D.B. (1991) Elaeophorosis in wild ruminants. Bulletin of the Society for Vector Ecology 16(1):149-160.
  2. Railliet, A. and A. Henry (1912) Nématodes vasculicoles des Bovins annamites." Bulletin de la Société de Pathologie Exotique 5(2):115-118.
  3. Anderson, R.C. and O. Bain (1976) "CIH Keys to the Nematode Parasites of Vertebrates." Commonwealth Agriculture Bureaux: Farnham, England, Vol. 3, pp. 59-116.
  4. Hernandez Rodriguez, S.; Martinez Gomez, F.; Gutierrez Palomino, P. (1986). "Elaeophora elaphi n. sp. (Filarioidea : Onchocercidae) parasite of the red deer(Cervus elaphus).With a key of species of the genus Elaeophora". Annales de Parasitologie Humaine et Comparée. 61 (4): 457–463. doi: 10.1051/parasite/1986614457 . ISSN   0003-4150. PMID   3813427. Open Access logo PLoS transparent.svg
  5. Cheng, Y.D. (1982) "A survey of parasitic nematodes in domestic animals and poultry from Lingling area, Hunan Province, with description of two new species." Acta Zootaxonomica Sinica 7(1):20-26. (not seen)