Comparison of measured and predicted energy availability of protein ingredients for broiler chickens

In this study, the apparent metabolizable energy corrected for nitrogen (AMEn) of the High Protein Dried Distillers Grains (HP-DDG), Dried Distillers Grains with Solubles (DDGS), extruded semi-whole soybeans (ESWS) with 8% and 12% ether extract (EE), and cottonseed meal (CM) with 28% and 38% crude protein (CP) for broiler was determined, comparing in vivo data with two equations. The study used randomized design with seven diets, six replicates (six birds/unit), and the Celite® partial collection method. Ingredient AMEn values were compared against equation-derived estimates (Tukey, P<0.05). The estimates of AMEn prediction equation 1 were: HP-DDG and DDGS (39.15 x dry matter - 39.15 x ashes - 9.72 x CP - 63.81 x EE), CM (21.26 x dry matter + 47.13 x EE - 30.85 x crude fiber) and ESWS (27.69 - 59.1 x crude fiber + 62.1 x EE). The equation 2 (4.31xDP + 9.29xDEE + 4.14xDNNE) are digestibility values. The AMEn determined values were: 3329 kcal/kg (HP-DDG), 2507 kcal/kg (DDGS), 3158 kcal/kg and 3519 kcal/kg (ESWS of 8% and 12% EE), 1579 kcal/kg and 2129 kcal/kg (CM 28% and 38% CP). HP-DDG's determined AMEn significantly exceeded estimates from Equations 1 (2425 kcal/kg) and 2 (2862 kcal/kg). AMEn for DDGS and ESWS (8% and 12%) did not differ from Equation 1 (2230, 2912 and 3209 kcal/kg, respectively). Equation 2 (1302 and 1611 kcal/kg, respectively) provided the best estimate for the AMEn of CM 28% and 38% CP. Evaluated ingredients are viable for broilers, despite variable predictive accuracy.