Procoid
As Prozerkoid the second is the larval stage of the tape worms of the family of Diphyllobothriidae (z. B. fish tapeworm or spirometra erinaceieuropaei ), respectively.
The unembryonated eggs of the Diphyllobothriidae get through the feces of infected animals into fresh or brackish water , where they grow into buoyant hook larvae ( Coracidium ). If the hook larvae are ingested by copepods , the procercoid larvae develop from the coracidium. The small crustaceans are in turn eaten by non-coarse fish as transport hosts, in whose muscles the plerozerkoid develops from the procercoid . The larval type , then known as Sparganum , accumulates in predatory fish when they eat the non- predatory fish. When raw fish meat is consumed by the final host (fish-eating birds and mammals , including humans ), the plerozerkoids, which develop into adult worms in the intestinal tract of the final host , are then taken up .
literature
- Winfried Ahne u. a .: zoology. Textbook for students of veterinary medicine and agricultural sciences. Schattauer, Stuttgart et al. 2000, ISBN 3-7945-1764-4 , pp. 207f.
- DRR Burt: Platyhelminthes and Parasitism. An Introduction to Parasitology. The English University Press, London 1970, ISBN 0-340-11462-2 ( Unibooks. Modern Biology Series ).
- Yezid Gutierrez: Diagnostic Pathology of Parasitic Infections with Clinical Correlations. 2nd edition. Oxford University Press, New York et al. 2000, ISBN 0-19-512143-0 .
- Hartmut Krauss, Albert Weber, Burkhard Enders a. a .: zoonoses. Infectious diseases that can be transmitted from animal to human. 3rd completely revised and updated edition. Deutscher Ärzte-Verlag, Cologne 2004, ISBN 3-7691-0406-4 , p. 439ff.