Arkansas Net Energy (Ark NE) is a NE system for ingredients and diets that provides actual productive energy and is dependent upon genetics, age, environment and nutrient content. The Ark NE values for complete diets and ingredients are based on performance, body composition and heat production providing net energy for maintenance (NEm) and net energy for gain (NEg). Broilers need a dietary energy system that reflects performance and high protein gains. The Ark NE and AMEn values of SBM and Corn were determined for starter, grower, and finisher I, II, and III feeding periods using dual energy x-ray absorptiometry (DEXA) and indirect calorimetry. Experiment 1 consisted of feeding three different levels of SBM in a corn-soybean meal basal diet in each feeding period. Experiment 2 consisted of feeding three levels of test corn substituted against a corn-soybean meal summit diet for each feeding phase. Data were subjected to a one-way ANOVA and Tukey’s HSD to compare separate treatment means with significance set at 0.05 using JMP pro 15.2. A linear regression model was used to establish the three energy values of SBM and corn for broilers d0-d56 of age. The Ark NE and AMEn values (kcal/kg diet or ingredient) were significantly increased (P < 0.05) for broilers fed the highest concentration of protein and digestible amino acids.
Overall, weighted values based on feed intake for 56d period for SBM Ark NE and AMEn were 3,028 and 2,342 kcal/kg. The respective Ark NE and AMEn weighted values of corn based on feed intake for 56d were 1,368 and 3,311 kcal/kg. Consequently, SBM weighted value for all feeding periods contributes 34% of the Ark NE for broiler diets, whereas SBM provides 21 % of AMEn calories for same diets. In contrast, corn contributes 40% of the Ark NE for diets, while it provides 77% of AMEn calories from same diets. Dietary Ark NE provides additional kcal for broilers from ingredients and diets providing digestible amino acids for lean mass gain (NEg) and fasting heat production (NEm).
