Dietary salt requirement for barramundi Asian seabass (Lates calcarifer, Bloch 1970) fingerlings reared in freshwater recirculation units

The present study was conducted to determine the dietary salt requirement for Asian seabass fingerlings reared in fresh water. Fingerlings (3.3 g) were fed salt-rich diets prepared by adding 5%, 6%, 7%, or 8% salt to a commercial pelleted fish feed. The feed was ground and re-pelleted after addition of the salt. The highest (p<0.05) growth and survival rates were obtained in fish fed the 6% salt-rich diet, followed by fish fed the 5% and control (no salt enrichment) diets. The best feed conversion and protein efficiency ratios were also obtained in groups fed the 6% diet. Fish fed the 8% salt-rich diet had the lowest growth and survival rates. Incorporation of salt in the diet was not detrimental to the fish.