DIGESTIBLE AND METABOLIZABLE ENERGY VALUES OF SOME FEEDS FOR THE GROWING PIG

Digestible energy (DE), metabolizable energy (ME) and metabolizable energy corrected to nitrogen equilibrium (MEn) were determined for eight feeds. Effects of protein level in the basal ration and of level of feeding certain test feeds were also studied. Protein level of the test ration was found to be inversely correlated with the ratio ME/DE (r = −0.956; P < 0.01). It was postulated that conventional methods for estimating ME and MEn underestimate high protein feeds and that, based on a regression equation, the ME values for swine feeds can be determined most effectively by multiplying DE × 0.98). This provides a metabolizable energy value applicable within the protein levels used in practical swine production. ME values thus derived were: soybean meal 3620, rapeseed meal 3280, herring fishmeal 4550, wheat 3965, barley 3175, oats 2900 and wheat shorts 3040 kcal/kg dry matter.