CHANGES IN BODY WEIGHT GAIN OF BLUE TILAPIA, OREOCHROMIS AUREUS DURING LONG-TERM EXPOSURE TO SUBLETHAL CONCENTRATIONS OF FORMALIN

Document Type : Original Article

Author

Central Laboratory for Aquaculture Research, Agricultural Research Centre, Ministry of Agriculture, Giza, Cairo, Egypt

Abstract

The effect of sublethal concentrations of formalin on the weight gain of blue tilapia fingerlings was investigated under laboratory condi­tions during a 12 weeks exposure period at concentrations of 32, 16, 8, 4, 2 mg/l and 0.00 (control). Due to this exposure, the weight gain was depressed in the fish. This depression was directly proportional to the formalin concentrations. However, at 2 mg/I concentration, no signifi­cant depression in weight gain (P>0.05) was observed in the tested fish. Precautions in the successful use of formalin in the treatment of external bacterial and parasitic infections in aquaculture fields are dis­cussed