ABSTRACT
Parasites associated with fish are mainly worms. There are two important phyla of worms that contain parasitic members. These are the flatworms and the roundworms. The primary host is typically a mammal, and the adult parasite infests the host's bile ducts, causing thickening, inflammation and blockage. The best control is the thorough cooking of all fish prior to eating. However, raw fish is a traditional delicacy in many parts of the world and is increasingly popular in the UK and USA. As with trematode parasites, the best control is to cook fish before eating. This destroys the encysted larvae. Immediate evisceration of fish will help to reduce infestation of the flesh as this will prevent the migration of the nematode larvae into the main fillets. A parasite is defined as an organism that lives in or on another organism, deriving shelter and/or nutrition from the host. The parasites have multi-stage life cycles involving intermediate hosts.
