The effects of nitrite on the short-term growth of silver perch (Bidyanus bidyanus)

Growing interest in the pond culture of silver perch (Bidyanus bidyanus) demands the determination of water quality parameters affecting production. The effect of nitrite on the survival and growth of silver perch fingerlings was evaluated in a 25-day experiment. Survival was not affected by exposures up to 16.2 mg 1-1 NO2-N. Growth was reduced at concentrations above 1.43 mg 1-1 NO2-N. The EC5 (the concentration at which growth is reduced by 5%) was estimated to be 2.78 mg 1-1 NO2-N. Changes in gill histopathology were observed in fish exposed to nitrite, relative to control fish, but the changes were not dose-dependent or consistent among fish exposed to the same nitrite concentration.