Stichocyte

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Stichocyte at the posterior extremity of the oesophagus in Capillaria aerophila. N: nucleus of the posteriormost stichocyte. Bar = 50 mm Eucoleus aerophilus female vulva.jpg
Stichocyte at the posterior extremity of the oesophagus in Capillaria aerophila . N: nucleus of the posteriormost stichocyte. Bar = 50 μm

Stichocytes are glandular unicellular cells arranged in a row along the posterior portion of the oesophagus, each of which communicates by a single pore with the lumen of the oesophagus. They contain mitochondria, rough endoplasmic reticulum, abundant Golgi apparatuses, and usually 1 of 2 types of secretory granules, α-granules and β-granules, indicating secretory function. [1] [2] [3] [4] [5] [6] [7] [8] Collectively stichocytes form the stichosome. Characteristic of Trichocephalida and Mermithida, [1] two groups of nematodes.

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<span class="mw-page-title-main">Linguatulosis</span> Medical condition

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Teladorsagia circumcincta is a nematode that is one of the most important parasites of sheep and goats. It was previously known as Ostertagia circumcincta and is colloquially known as the brown stomach worm. It is common in cool, temperate areas, such as south-eastern and south-western Australia and the United Kingdom. There is considerable variation among lambs and kids in susceptibility to infection. Much of the variation is genetic and influences the immune response. The parasite induces a type I hypersensitivity response which is responsible for the relative protein deficiency which is characteristic of severely infected animals. There are mechanistic mathematical models which can predict the course of infection. There are a variety of ways to control the infection and a combination of control measures is likely to provide the most effective and sustainable control.

<span class="mw-page-title-main">Stichosome</span>

Stichosome is a multicellular organ that is very prominent in some stages of nematodes and consists of a longitudinal series of glandular unicellular cells (stichocytes) arranged in a row along the oesophagus that form the posterior esophageal glands. It opens into the esophageal lumen and apparently functions as a secretory gland and storage organ.

Echinostoma caproni is a species of 37-spined Egyptian echinostome. It is naturally found in Cameroon, Congo, Egypt, Madagascar, and Togo.

<i>Cooperia oncophora</i> Species of roundworm

Cooperia oncophora is one of the most common intestinal parasitic nematodes in cattle in temperate regions. Infections with C. oncophora may result in mild clinical symptoms, but can lead to weight loss and damage of the small intestine, especially when co-infections with other nematodes such as O. ostertagi occur. Infections are usually treated with broad-spectrum anthelmintics such as benzimidazole, but resistance to these drugs has developed in the last decades and is now very common. C. oncophora has a direct life cycle. Infective larvae are ingested by the host. The larvae grow to adults, which reproduce in the small intestines. Eggs are shed onto the pasture with the faeces, which leads to new infections. Co-infections with other gastro-intestinal nematodes such as O. ostertagi and H. contortus are common.

References

  1. 1 2 Chitwood, B. G. & Chitwood, M. B. (1950). Introduction to Nematology (Vol. 1). Baltimore: Monumental Printing Co. doi : 10.5962/bhl.title.7355
  2. Peter J. Gosling. Dictionary of Parasitology. 2005
  3. Heinz Mehlhorn. Encyclopedia of Parasitology. 3rd Edition 2008
  4. Larry Roberts, John Janovy. Foundations of Parasitology. 8th edition 2008
  5. Michael Hutchins, Donna Olendorf. Grzimek's Animal Life Encyclopedia: Lower metazoans and lesser deuterosomes. 2004
  6. HG Sheffield. Electron microscopy of the bacillary band and stichosome of Trichuris muris and T. vulpis. Journal of Parasitology, 1963
  7. Despommier, DD; Müller, M (Oct 1976). "The stichosome and its secretion granules in the mature muscle larva of Trichinella spiralis". Journal of Parasitology. 62 (5): 775–85. doi:10.2307/3278960. JSTOR   3278960. PMID   978367.
  8. Lalošević, V.; Lalošević, D.; Capo, I.; Simin, V.; Galfi, A.; Traversa, D. (2013). "High infection rate of zoonotic Eucoleus aerophilus infection in foxes from Serbia". Parasite. 20: 3. doi:10.1051/parasite/2012003. PMC   3718516 . PMID   23340229.