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).
Keywords: Helminths; Iran; Silurus glanis; Zarrine-roud.