Effects of Nitrite Exposure on Growth and Survival of Sea Bass, Lates calcarifer, Fingerlings in Various Salinities

Abstract

Sea bass, Lates calcarifer, fingerlings were acclimated to 0. 15, and 32 ppt, and the toxic effects of nitrite exposure were assessed. The 96-hour median lethal concentrations (96-hour LC₅₀ for nitrite were estimated to be 14.5 mg/L at 0 ppt, 105 mg/L at 15 ppt and 93 mg/L at 32 ppt salinity. Chronic exposure to a nitrite concentration equivalent to 10% of the respective 96 hour LC₅₀ resulted in marked growth reduction: growth being reduced in the order of 0 ppt > 32 ppt > 15 ppt. In nitrite-free water, growth rate for fish raised at a salinity of 15 ppt was higher compared to fish raised at salinities of 0 ppt and 32 ppt, a phenomenon which probably reflected the advantage of a reduction in osmoregulatory work in an iso-osmotic environment.