Energy represents a major cost in feed formulation. This study intended to develop a model to predict the productive energy (PE) of corn based on its content of digestible nutrients, including digestible crude protein (dCP, %), digestible fat (dFA, %), digestible starch (dST, %), and broiler age, compared to apparent metabolizable (AMEn) and classic net (CNE) energy. Four experiments (E1 to E4) were conducted 1-56 d in floor pens with diets formulated following Cobb 500 guidelines. Pelleted treatment diets (5-phase feeding program) included SBM dilutions with cellulose (E1) or corn (E2) and graded levels of oil (E3) or total digestible amino acids (E4). Body composition (Dual Energy X-Ray Absorptiometry, DEXA), heat production (calorimetry chambers), performance, and digestible nutrients of 60 test diets were assessed. The PE value of corn was determined by regression (E1, E2), and the digestible nutrient profiles of 4 corn batches were characterized (E1 to E4). Nutritional values of corn batches varied in dCP (7.54– 9.26%), dFA (2.41–3.42%), and dST (52.5–56.8%). A database was built up (n=646), and data were analyzed in JMP using mixed models. A multiple linear model was obtained (E1 to E4) applying a stratified random data-splitting with a refitting approach to predict corn PE considering dCP, dFA, dST, and age (d) as fixed predictors: PE (kcal/kg) = 136.5 + 80.55 dCP + 65.29 dFA + 35.49 dST – 13.66 age – 0.454 (age – 31.1548)2 (every predictor P<0.0001; adj. R2 = 0.62). The model was validated. dST, dCP, and dFA in corn explained 72.8, 20.8, and 6.4% of its PE value. Mean predicted corn PE values were 2,755, 2,792, 2,656, 2,435, and 2,183 kcal/kg in Starter, Grower, Finisher 1, Finisher 2, and Finisher 3, respectively. The mean PE values of 4 corn batches used in the experiments were 2,379, 2,491, 2,379, and 2497 kcal/kg. FCR and feed intake were correlated more with PE than AME or CNE (>adj. R2; < P value). In conclusion, the PE value of corn can be predicted for diverse feeding programs based on its digestible nutrient content and broiler age, and it is a better predictor of performance.

Martinez, D., N. Suesuttajit, C. Umberson and C. Coon. 2025.  The Productive Energy Value of Corn as Determined by its Content of Digestible Nutrients and Broiler Age 2025 International Poultry Scientific Forum, Abstract P388.