Chemical composition, energy values, digestibility coefficients and the values of true amino acid of by-products from slaughterhouses were determined by using the method of "forced feeding" with cecectomized roosters. It was used a complete random design, with two types of fish meal (FM1 and FM2), two types of meat and bone meal (MBM1 and MBM2) and one fasting diet, using six replications with one rooster per experimental unit. The values for apparent metabolizable energy (AME), nitrogen corrected AME (AMEn), true metabolizable energy (TME) and nitrogen corrected TME (TMEn), expressed in kcal/kg as fed basis, were 3060, 3188, 2347 and 2191 for FM1, 3238, 3181, 2603 and 2,377 for FM2, 3932, 4057, 3182 and 3026 for MBM1 and 3399, 3710, 2587 and 2501 for MBM2, respectively. Coefficients of metabolizability, in percentage of gross energy (GE), of AME, AMEn, TME and TMEn were: 61.42, 64.99, 78.94 and 68.23 for FM1; 63.58, 63.45, 80.94 and 74.00 for FM2; 52.67, 58.40, 71.40; 58.05 for MBM1 and 49.04, 53.20, 67.73 and 55.97 for MBM2. The average values of true digestibility of essential and non essential amino acids, in percentage, for FM1, FM2, MBM1 and MBM2 were: 94.32 and 92.87; 92.95 and 90.47; 83.24 and 76.94 and 83.83 and 76.96, respectively.
apparent metabolizable energy; broiler chickens; digestibility coefficients; slaughterhouse by-products; true metabolizable energy
