|
''Taenia'' is a genus of tapeworms (a type of helminth) that includes some important parasites of livestock. Members of the genus are responsible for taeniasis and cysticercosis in humans, which are a type of helminthiasis belonging to the group of neglected tropical diseases. More than 100 species are recorded. They are morphologically characterized by a ribbon-like body composed of a series of segments called proglottids; hence the name ''Taenia'' (Greek ταίνια, ''tainia'' meaning ribbon, bandage, or stripe). The anterior end of the body is the scolex. Not all members of the genus ''Taenia'' have an armed scolex (hooks and/or spines located in the "head" region), for example, ''Taenia saginata'' has an unarmed scolex, while ''Taenia solium'' has an armed scolex.〔Roberts, L.S. and Janovy, John Jr. ''Foundations of Parasitology'' 7th Edition. McGraw-Hill. 2005.〕 Proglottids have a central ovary, with a vitellarium (yolk gland) posterior to it. As in all cyclophyllid cestodes, a genital pore occurs on the side of the proglottid. Eggs are released when the proglottid deteriorates, so a uterine pore is unnecessary. ==Selected species== * ''Taenia asiatica'', the Asian taenia, has humans as definitive hosts, and pigs and rarely cattle as intermediate hosts. * ''Taenia crassiceps'' usually infects canines and also rodents, but rarely infect humans. * ''Taenia gonyamai'' is parasite of antelope (as larvae) and lions (as adults). * ''Taenia mustelae'' infects small carnivorans. * ''Taenia pisiformis'' is common in wild dogs and in rabbits, which serve as intermediate hosts. * ''Taenia rileyi'' infects bobcats. * ''Taenia saginata'', beef tapeworm, infects cattle and humans, and can only reproduce while in the human gut. * ''Taenia solium'', pork tapeworm, like ''T. saginata'', has humans serving as its primary host, and it can only reproduce by the dispersal of proglottids while in the gut. These reinfect pigs when human faeces are improperly disposed of. This infection is most common in parts of Africa. * ''Taenia taeniaeformis'' uses rodents as intermediate hosts and then inhabits cats as the definitive hosts. * ''Taenia serialis'' is a parasite of dogs and foxes which has rabbits as the intermediate host. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Taenia (genus)」の詳細全文を読む スポンサード リンク
|