Apparent metabolizable energy and prediction equations for reduced-oil corn distillers dried grains with solubles in broiler chicks from 10 to 18 days of age

Abstract

An experiment consisting of 2 identically designed trials was conducted to determine the nutrient composition and AMEn content of distillers dried grains with solubles (DDGS) to develop prediction equations for AMEn in broilers. Fifteen samples of DDGS ranging in ether extract (EE) from 3.15 to 13.23% (DM basis) were collected from various dry-grind ethanol plants and were subsequently fed to broiler chicks to determine AMEn content. A corn-soybean meal control diet was formulated to contain 15% dextrose, and test diets were created by mixing the control diet with 15% DDGS at the expense of dextrose. In each trial, 672 male Ross × Ross 708 chicks were housed in grower battery cages with 7 birds per cage (0.06 m2/bird) and received a common starter diet until 10 d of age. Each cage was randomly assigned to 1 of 16 dietary treatments, with 6 replicate pens per treatment. Experimental diets were fed over a 6-d acclimation period from 10 to 16 d of age, followed by a 48-h total excreta collection period. Gross energy (GE) and CP of the experimental diets and excreta were determined to calculate AMEn for each DDGS sample. On a DM basis, AMEn of the 15 DDGS samples ranged from 1,869 to 2,824 kcal/kg. Analyses were conducted to determine the GE, CP, EE, DM, starch, total dietary fiber (TDF), neutral detergent fiber (NDF), acid detergent fiber (ADF), and ash content of the DDGS samples. Stepwise regression resulted in the following best-fit equation for AMEn (DM basis) based on the adjusted coefficient of determination (R2adj), SE, and prediction error sum of squares (PRESS): AMEn, kcal/kg = −12,282 + (2.60 × GE) + (89.75 × CP) + (125.80 × starch) – (40.67 × TDF; R2adj = 0.86; SE = 98.76; PRESS = 199,819; P ≤ 0.001). These results indicated that the composition of DDGS with variable EE content may be used to predict AMEn in broiler chicks.