Identification and Treatment of Hexamitiasis Observed in Rainbow Trout (Oncorhynchus mykiss) Fry

In this study, hexamitiasis which is a fatal disease in 0.5-10g of rainbow trout fry in different fish farms in the Eastern Black Sea Region of Turkey was investigated between 2006 and 2016. A total of 360 diseased fish was examined monthly. The highest mortality rate in fish was observed in spring and autumn months and their infestation continued throughout the year. Diagnosis was made by observation of the hexamita in feces contents from gut in light microscopy. Different chemotherapeutics such as albendazol, metronidazole, trichlorfon, toltrazuril and magnesium sulphate were applied on rainbow trout (Oncorhynchus mykiss) fry for treatment of infestation. Albendazol and metronidazole were founded as the most effective treatment