Comparison of digestible energy of blood meals and poultry by-product meals for pigs using the digestible protein and fat method and the replacement method

Two experiments (EXP) were carried out with 49 and 65 kg barrows (EXP I and 2, respectively) to determine digestible energy (DE) values of three sources of blood meals (EXP 1): conventional (CBM), flash dried (FDBM) and spray dried red blood cells (SDRBC), and of three poultry by-product meals (EXP 2) (PBM-10.1, PBM-12.7, and PBM-16.7% of ash content) by an alternative method to the replacement method (SbM). The method was based on the starch basal diet replacement with increasing levels of ingredient test (7 and 14%). Digestibility coefficients of protein (DCP) and fat (DCF) were obtained by the regression analysis between the percentage of added protein (or fat) in the basal diet and the dietary digestible protein (or digestible fat) percentage. Total feces collection was performed, during 5 days, for the digestibility assays, after 4 days of adaptation. Another treatment consisted of starch basal diet replacement with 25% of CBM or PBM-10.1 to determine DE by SbM. The DCP, DE and AME were of 30%, 1,432, and 1,246 kcal/kg for CBM; 86.7, 4.185, and 3,648 kcal/kg for FDBM and 84.6%, 4,041, and 3.512 kcal/kg for SDRBC, respectively. Regression lines difference was found between CBM and the other two sources. DE of CBM measured by SbM was of 988 268 kcal/kg. For PBM-10.1, PBM-12.7 and PBM-16.7, DCP, DCF, DE and AME were, respectively, 93.0, 87.6, 4,106, 3,719, 96.4, 85.6, 4,390, and 3,987 and 84.3%, 80.5%, 3,925, and 3,580 kcal/kg. Regression lines difference was found between PBP-16.7 and the other two sources for DCP. For DCF lines, no differences were found. DE value of PBM 10.1, measured by SbM, was of 4,057 164 kcal/kg. It is probable that SbM underestimate ingredient DE, specially for those with little palatability, as blood meals. The alternative method is a good option for DE calculations.