ABSTRACT
A study was conducted to evaluate fish meal-free practical diets, with and without amino acid supplementation, for the rearing of first feeding Nile tilapia, Oreochromis niloticus. A basal diet was formulated that appeared marginally deficient in lysine, methionine and threonine; thus, experimental diets were supplemented with all possible combinations of those three essential amino acids. Diets contained 45% crude protein and 12% lipid. Diets were fed to apparent satiation four times daily (0800,1100,1400, and 1700 hours) for a period of 30 days. No significant differences (P < 0.05) in specific growth rate, weight gain, apparent consumption, food conversion ratio or survival were observed. A significant difference (P < 0.01) in protein retention was observed between fish fed the positive control diet (51.84%) and experimental treatments (22.80–35.17%). This initial evaluation of fish meal-free practical diets for first feeding Nile tilapia demonstrates the potential for eliminating fish meal in diets for larval tilapia, but additional research appears needed to enhance retention of amino acids.