Thirty two crossbred lambs were used in a 70 day study at Embrapa Caprinos, in Sobral, CE, Brazil to evaluate the influence of concentrate levels on finishing diets under confinement. The treatments were the following roughage to concentrate relations: 100% to 0% (T1), 85% to 15% (T2), 70% to 30% (T3) and 55% to 45% (T4). The roughage was cunhã hay (Clitoria ternatea L), and the concentrate was composed of corn (75%) and soybean meal (25%). The adjustments of the proportions were made daily, based on the roughage intake, served ad libitum. It was observed that the total dry matter intake increased, the forage intake decreased, the feed efficiency improved and the daily weight gain increased (P<0.01) with the increase in diet concentrate. Additionally, it was observed a quadratic effect on forage intake and feed efficiency with minimum values of 25.99g of concentrate/kg0,75/day and 21.12g of concentrate/kg0,75/day, respectively. All profit/monetary units were positive and did not differ (P>0.05) among treatments. It was concluded that any of the diets studied can be used for finishing lambs.
feed efficiency; feed intake; sheep weight gain