A survey on endoparasitic infection of rainbow trout (Oncorhynchus mykiss) in fish farms in Khoy, Iran.

Objective: The objective of this study was to determine endoparasitic infection of rainbow trout (Oncorhynchus mykiss) in fish farms of Khoy, Iran. Method & Materials: In this study 70 rainbow trouts (Oncorhynchus mykiss) in different ages, from 10 fish farms of Khoy were studied for parasitic infection. Eye, abdominal cavity and gastrointestinal tract were examined under loupe. Then wet mount specimens were prepared and studied under microscope. Results & Conclusion: In one female fish oocysts of Eimeria and in one male rainbow trout (Oncorhynchus mykiss) metacercariae of Diplostomum spataceum were detected. Development of modern fish farm and increase in number of the farms give rise to epidemics of parasitic infestation nowadays. Because of growth of investment in this sector in recent years and increasing of fish farms strict hygienic regulations should be taken in to consideration