Study and identification of external parasites in imported goldfish (Carassius auratus) into Iran

Ornamental fish keeping is increasing in Iran and around the world, but more in freshwater fishes than the marine’s. Most of such fishes are importing and not native in Iran. Among the infectious microorganisms, they face more with parasitic disease. Ectoparasites are the important concern in ornamental fish keeping. In this study one hundred and fifty goldfish were investigated for gills and skin external parasites in 2018 winter. These samples were transferred to the lab in their original-country water. Forty eight out of samples (%32) were free from parasites and in 102 out of samples parasitic pollution was observed in skin or /and gills. Six species of parasites were isolated from polluted fish that three were protozoan (two species of Trichodina and Ichthyophtirius multifiliis) and three were metazoan monogenetic parasites (Dactylogyrus formosus, Dactylogyrus baueri and Gyrodatylus sp.). Ichthyophtirius multifiliis was only observed in fish skin. The other parasites were present in gills and skin. Supervision on health condition of aquarium fishes in international trades or inter province deals is one of the most necessities in disease prevention. Any deals without a health certificate maybe risky and harmful.