The objective ofthe present study was to evaluate the protein requirement of juvenile Trichogasterlalius, blue variety. The experimental design was of randomised blocks (B1= initial weight of 1.04±0.05 g and B2 = 1.36±0.02 g), with tworeplicates within each block and five treatments (230, 270, 310, 350 and 390g CP/kg diet). The fish were fed to satiation, three times a day for 90 days.The study evaluated: survival rate, weight gain, final length, feed intake,feed conversion ratio, protein efficiency ratio, specific growth rate and conditionfactor. There was a linear effect of dietary protein levels for protein efficiencyratio, specific growth rate (positive linear effect) and feed conversion ratio(negative linear effect). For weight gain, final length, feed intake and conditionfactor a quadratic effect of dietary protein levels was observed, with estimatedvalues of 409.8, 366.2, 317.4 and 365.0 g CP/kg diet, to improve their performanceparameters. Analysis of growth based on the length of the fish shows that 366.2g of CP/kg diet meets the protein requirement of juvenile Trichogaster lalius,blue variety.
