the occurrence of helminth parasites in the gastrointestinal of catfish (silurus glanis linnaeus 1758) from the zarrine-roud river, iran

this investigation was undertaken to verify the prevalence of helminths parasites in the gastrointestinal tract of catfish. a total number of 116 catfish (silurus glanis) were collected from zarrine-roud river and examined for helminths. fish were examined after washing contents of gastrointestinal tract and observed for the presence of helminths using a stereo microscope and a light microscope. results indicated that 18.96% of the examined catfish were infected with digenean trematodes including orientocreadium siluri (27%), crowcrocoecum skrjabini (39%), and cestode bothriocephalus gowkongensis (34%). all the parasites were found in the intestine. mid-gut followed by foregut appeared to be the most commonly infected parts of the alimentary tract of hosts. the results showed that there was a significant correlation between infection rate, catfish body size, and weight (p < 0.05).