Taenia pisiformis

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Taenia pisiformis
Taenia scolex cropped.jpg
Taenia pisiformis scolex
Scientific classification
Kingdom: Animalia
Phylum: Platyhelminthes
Class: Cestoda
Order: Cyclophyllidea
Family: Taeniidae
Genus: Taenia
Species: T. pisiformis
Binomial name
Taenia pisiformis
Bloch 1780
Synonyms[1]

Taenia novella Nuemann, 1896
Cysticercus pisiformis Zeder, 1803

Taenia pisiformis, commonly called the dog tapeworm, is an endoparasitic tapeworm which causes infection in lagomorphs, rodents, and carnivores. Adult T. pisiformis typically occur within the small instenstines of the definitive hosts, the carnivores. Lagomorphs, the intermediate hosts, are infected by fecal contamination of grasses and other food sources by the definitive hosts. The larval stage is often referred to as Cysticercus pisiformis and is found on the livers and peritoneal cavities of the intermediate hosts.[2] T. pisiformis can be found worldwide.

Description[edit]

T. pisiformis typically infect dogs and other carnivores such as coyotes and foxes. Within rabbits, T. pisiformis larvae attach themselves to the liver and intestines, forming cysts 5–7 mm (0.20–0.28 in) in diameter. This is referred to as cysticercosis.[3]

In adult T. pisiformis, the long hooks of the scolex are on average 239.9 µm (0.00944 in) and the short hooks are 140.1 µm (0.00552 in). The dimensions of the suckers are 322.3 µm × 288.1 µm (0.01269 in × 0.01134 in).[4] They can have from 34 to 38 hooks which can be up to 234 µm (0.0092 in) in length.[5] Adult T. pisiformis can grown between 0.5 to 2 m (20 to 79 in).[5]

The intermediate host is represented by hares and rabbits, in which we find the mesacestoide (the larval stage) known as: cysticercus pisiformis. This is found in the peritoneum of the intermediate host and can be ingested by the definite host when the dog or cat feeds on the viscera of such an infected intermediate.[citation needed]

Adult morphology[edit]

The adult stage consists of a scolex with four suckers and an armed rostellum, a short neck region, a series of immature proglottids with undeveloped reproductive organs, a series of mature proglottids with fully developed male and female reproductive organs, and a series of gravid proglottids with an expanded uterus filled with eggs.[citation needed]

Gallery[edit]

References[edit]

  1. ^ Hall, M.C. (1920). "The adult taenioid cestodes of dogs and cats, and of related carnivores in North America". Proceedings of the United States National Museum 55 (2258): 1–94. 
  2. ^ Owiny, J.R. (March 2001). "Cysticercosis in laboratory rabbits". Journal of the American Association for Laboratory Animal Science, 40 (2): 45–48. 
  3. ^ "Cysticercosis". Michigan Department of Natural Resources. Retrieved 18 October 2014. 
  4. ^ Esch, G.W.; Self, J.T. (December 1965). "A critical study of the taxonomy of Taenia pisiformis Bloch, 1780; Multiceps multiceps (Leske, 1780); and Hydatigera taeniaeformis Batsch, 1786". Journal of Parasitology 51 (6): 932–937. JSTOR 3275873. 
  5. ^ a b Underhill, B.M. (1920). Parasites and parasitosis of the domestic animals. New York: Macmillan. p. 179. 

Further reading[edit]

  • Roberts, L.S.; Janovy, J. (2008). Foundations of Parasitology (8th ed.). Boston: McGraw-Hill. p. 347. ISBN 9780073028279.