Man may become infested with this fluke by eating uncooked vegetables.Gibsons Online supply a wide range of Animal Health products including Levafas Diamond, Ivomec Super Injection, Closamectin, Dectomax Injection, Vexocan and Triclaben at Gibsons Online. hepatica causes the highly destructive “liver rot” in sheep and other domestic animals. Human hosts may die from severe infestations.įlukes of detrimental economic significance to man include the widely occurring giant liver fluke of cattle ( Fasciola hepatica) and the Chinese, or Oriental, liver fluke ( Opisthorchis sinensis, or Clonorchis sinensis). Some eggs are carried in the bloodstream to various organs and may cause a variety of symptoms, including enlargement of the liver. The adult occurs in the veins of the small intestine. Snails of the genus Oncomelania are the intermediate host. haematobium in that it may attack vertebrates other than man, including various domestic animals, rats, and mice. The Oriental blood fluke, which occurs primarily in China, Japan, Taiwan, the East Indies, and the Philippine Islands, differs from S. The larva enters the body of a snail (any of several genera), the intermediate host, and returns to a human host through the skin. The eggs pass from the host with the feces. mansoni), which lives in the veins around the large and small intestines, occurs primarily in Africa and in northern South America.
The mature larva makes its way into the body of the final host, man, through the skin or the mouth. The larval fluke develops in the body of a snail (chiefly of the genera Bulinus and Physopsis), the intermediate host. Eggs, laid in the veins, break through the vein wall into the bladder and are voided during urination. haematobium), which lives in the veins of the urinary bladder, occurs mainly in Africa, southern Europe, and the Middle East.
The human diseases caused by them are known as schistosomiasis (bilharziasis) they affect millions of persons, particularly in Africa and east Asia. mansoni), and the Oriental blood fluke ( S. Get a Britannica Premium subscription and gain access to exclusive content.īlood flukes occur in most types of vertebrates three species attack humans: the urinary blood fluke ( Schistosoma haematobium), the intestinal blood fluke ( S. Most species pass through egg, larval, and mature stages. In some, however, the sexes are separate. Most species are hermaphroditic i.e., functional reproductive organs of both sexes occur in the same individual. The nervous system consists of a pair of anterior ganglia, or nerve centres, and usually three pairs of lengthwise nerve cords. An anus is usually absent, but some species have one or two anal pores. The digestive system consists of a simple sac with a mouth either at the anterior end or in the middle of the ventral surface. The body is solid and filled with a spongy connective tissue (mesenchyme) that surrounds all the body organs. Muscular suckers on the ventral (bottom) surface, hooks, and spines are used for attachment. Most are flattened and leaflike or ribbonlike, although some are stout and circular in cross section. The symmetrical body of a fluke is covered with a noncellular cuticle. The flukes (Trematoda) are a class of parasitic worms belonging to the phylum Platyhelminthes.
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