The aim of this work was evaluate the effectof supplementation with different energetic sources, on growing steers performanceand economical viability, and also evaluate the structure and chemical compositionof Signalgrass (Brachiaria decumbens) from July to November, on SãoPaulo state west region. Forty-two animals (Nelore) and three pastures of 7.2ha each, were used. The energy sources used for supplements were: corn and cobwith husks (CCH), cassava meal (CM) and soybean hulls (SH); each treatment hadcottonseed meal to reach 25% of CP, and was given at 1.30% of BW. The animalweight was verified at each 14 days and forage characteristics were evaluatedat each 28 days. The average availability of forage was 2570 kg DM/ha and 1306kg leaves/ha. Leaves proportion showed a quadratic behavior in function of experimentalperiod, with minimum value of 46.58 % observed in August. The average levelsof CP were 4.45% for all plant, 5.30% for leaf e 2.83% for steam. The averagelevels of NDF and ADF were, respectively 70.61% and 39.93% for all plant, 65.76%and 34.91% for leaf, and 75.83% and 47.90% for steam. The supplements were notdifferent on average daily gain, with average of 0.836 kg/animal/day. The supplementmore economically viable was the cassava meal, which showed lesser coasts andbigger animal gain with better relation income:costs.
