Standardized ileal phosphorus digestibility of meat and bone meal and poultry byproduct meal for broilers

Abstract

Two experiments were conducted using direct method to determine the standardized ileal phosphorus (P) digestibility coefficient (SIPDC) of meat and bone meal (MBM) and poultry byproduct meal (PBM) for broilers. In the first experiment, three MBM from different batches were evaluated, with four treatments (MBMI, MBMII, MBMIII, and a P-free diet) and nine replicates of seven birds each, totaling 252 birds distributed across a completely randomized design. The P-free diet was used to determine endogenous P losses. Titanium dioxide (5 g kg-1) was used as an indigestible indicator. In the second experiment, three PBM from different batches were evaluated, with 189 birds distributed over three treatments (PBMI, PBMII, and PBMIII) and nine replicates of seven birds each. These two experiments were conducted when birds were 19-22 days old. The birds were euthanized to collect the ileal content. Using the P-free diet, endogenous P losses were determined at 94.9 mg kg-1 dry matter intake. Standardized ileal P digestibility of MBMI (0.65) and MBMIII (0.69) was higher compared with MBMII (0.49). The SIPDC determined for three PBM sources were similar and 0.96, 0.96, and 0.93 for PBMI, PBMII, and PBMIII, respectively. The present study demonstrates that P in MBM is not as available as it is believed and that the variability between batches should be considered by nutritionists, while PBM can be considered an excellent P source to broiler diets.