Nutritional composition and prediction of energy values of poultry offal meal and meat and bone meal for broilers

This study evaluated the apparent metabolizable energy (AME) and nitrogen-corrected AME (AMEn) of poultry offal meal (POM) and meat and bone meal (MBM) in broilers at different ages. Three metabolism trials were conducted in the pre-initial (1–8 days), starter (14–22 days), and grower (28–36 days) phases using 840 Cobb-500 broilers. Birds were housed in metabolic cages, and excreta were collected using the partial collection method. The experiment followed a completely randomized design with seven treatments and six replicates, with 10, 6, and 4 birds per phase. Treatments included a control diet and six test diets (80% control + 20% test ingredient: POM 1, 2, 3; MBM 1, 2, 3). AMEn values ranged from 3,189.7 to 3,342.9 kcal/kg in POM and 2,292.1 to 2,345.4 kcal/kg in MBM. Multiple regression equations were developed to predict AMEn. For POM, the best equation was AMEn = 6802 ‒ 213.3 (ether extract) ‒ 127.3 (calcium) + 10.47 (age) (R² = 0.92). For MBM, the equation was AMEn = 2789 ‒ 72 (ether extract) + 14 (calcium) + 20.28 (age) (R² = 0.91). These equations effectively estimate AMEn based on chemical composition and broiler age.