Report of Tetrahymena sp. and Dactylogyrus sp. infestation in glofish tetra (Gymnocorymbus ternetzi): Diagnosis and treatment

Cultivation and propagation of ornamental fishes have been increasing in the last years in Iran. The Glofish is patented and trademarked brand of genetically engineered fluorescent fish. GloFish® fluorescent fish come in a variety of species and colours of tropical fish including tetra. In an ornamental fish farm of Glofish tetra (Gymnocorymbus ternetzi), mortality of ۲۰ to ۳۰ per day were reported in juveniles and ۴ to ۶ per day in adult fish. Several fish were sent with their aquarium water for sampling. Wet smears were taken from the skin and gill. After the autopsy, the internal organs were examined for parasitic infestation under a light microscope. No internal parasites were observed. External parasites including Dactylogyrus sp. in the gills and Tetrahymena sp. in the skin were detected. According to references, treatment with salt bath and formalin ۳۷% was performed separately. A reduction in mortality was observed during the treatment period. After two weeks, re-sampling was performed and the samples were negative for Tetrahymena sp. and Dactylogyrus sp. Salt bath and formalin was effective for the treatment of Tetrahymena sp. and Dactylogyrus sp. in Glofish tetra.