Determination and Prediction of Digestible and Metabolisable Energy of Dehulled and Regular Soybean Meals for Pigs

The digestible energy (DE) and metabolisable energy (ME) content of seven dehulled and seven regular soybean meals were determined in growing pigs fed cornstarch- soybean meal diets using the total fecal collection method. The energy values for the dehulled soybean meals were higher than for the regular soybean meals. The mean DE and ME values for the seven dehulled soybean meals averaged 16.91 and 15.85 MJ/kg DM, respectively, while the corresponding values for the seven regular soybean meals averaged 16.79 and 15.54 MJ/kg DM, respectively. The chemical composition of each sample was determined and used to establish prediction equations (R2>0.90, RSD<0.1) for DE and ME values. Chemical components included in the prediction equations included ash (%), calcium (Ca), ether extract (EE), acid detergent lignin (ADL), nitrogen free extract (NFE), acid detergent fiber (ADF) and soluble carbohydrate (SCHO). The best equations for predicting DE and ME (MJ/kg DM) were as follows: DE = 25.3 - 0.70ash + 2.59Ca - 0.22EE + 0.41ADL - 0.099NFE (R2=0.98, RSD=0.025) ME = 25.0 - 0.65ash + 0.12ADF - 0.16NFE - 0.059SCHO (R2=0.98, RSD=0.019). The correlation between the determined DE and the predicted DE values as well as between the determined ME and the predicted ME values were significant while the differences between predicted and determined values were not significant (P>0.05), which indicates that the above prediction equations are suitable to predict DE and ME values of soybean meal for swine.