Impact of processing conditions and chemical composition on energy utilisation of expeller-extracted canola meal for broiler chickens

Low metabolizable energy content is regarded as one of the factors restricting high inclusion level of canola meal (CM) in broiler diets. It is known that expeller-extracted CM has higher energy content than solvent-extracted CM because the former contains higher residual oil (Woyengo et al., 2010). However, the impact of other chemical constituents is usually overlooked. The present study was designed to investigate the effect of processing conditions and chemical composition on AME and AMEn of six expeller-extracted canola meal samples (ECM) subjected to 90, 95 or 100° C and high or low screw force during oil extraction. The ECM samples were incorporated into a corn-soybean meal reference diet at 300 g/kg by replacing the energy yielding ingredients. A total of 210 day-old male broiler chicks (Ross 308) were fed a common starter and grower diet until 18 d of age, and then were assigned to each of seven experimental diets replicated six times with five chicks per cage. After a 5-d diet acclimation period from 18 to 22 d of age, a 72-h excreta collection period from 22 to 25 d was conducted. The difference method was used to determine AME which was corrected to zero N balance to obtain AMEn.