The traditional method of total collection was used to determine the values of apparent metabolizable energy (AME), corrected apparent energy (AMEn), true metabolizable energy (TME) and corrected true energy (TMEn) of eleven feedstuffs and the respective coefficients of metabolizability of GE. The feedstuffs were as follows: three samples of poultry by-product (PBP), three of feather meal (FM), two of meat and bone meal (MBM), two of swine viscera meal (SVM) and one of viscera and feather meal (VFM) of different origins. Three hundred and sixty male Ross broiler chickens, with 21 days old, were assigned to a randomized block design with eleven treatments and one control, with two replicates per block and five birds per experimental unit. The feedstuffs replaced 20% of the control. The birds were fed ad libitum during 12 days (last five days for total feces collection). During the collection, 30 poultry were allotted to six cages and fasted for 72 hours (the first 24 hours were for the gastrointestinal emptying and the 48 hours remaining for feces collection, that were quantified and extrapolated for five days). The average values of AME and AMEn expressed in kcal/kg on DM basis were as follows: 1,647 and 1,422 for MBM, 2,143 and 1,875 for FP, 3,062 and 2,844 for PBP, 1,889 and 1,779 for SVM and of 2,497 and 2,209 for VFM. The average values of TME and TMEn expressed in kcal/kg of DM, were: 1,753 and 1,462 for MBM, 2,269 and 1,452 for FM, 3,211 and 2,740 for PBM, 2,002 and 1,562 for SVM and 2,615 and 1,944 for VFM.
apparent metabolizable energy; broiler chicks; coefficients of metabolizability; true metabolizable energy
