A comparative study on amino acid availability of moist heated canola meal for poultry vs. ruminants

The objectives of this work were to measure the effect of moist heat treatment of canola meal (CM) on AA availabilities in poultry relative to ruminants, and to determine whether CM heated to increase rumen escape of protein could be used for poultry. Four groups of nine cockerels were randomly assigned to one of four treatments: untreated CM (control), CM moist heated (127°C) for 15 min, 45 min, and 90 min. Bioavailabilities of AA in CM for poultry were determined using the force-fed rooster technique. The resulting true available AA (TAAA) values were then compared with small intestinal AA disappearance values which were determined in steers. In poultry, 15 min heat treatment had no negative effects (P > 0.05) on the TAAA values of all essential AA except methionine, lysine, and threonine which were reduced (P < 0.05). Prolonged heat treatment (90 min) reduced (P < 0.05) the TAAA values of all essential AA. In terms of amounts of available AA (g kg−1 DM CM), 15 min heat treatment did not influence (P > 0.05) available methionine, threonine, phenylalanine, tryptophan and arginine, and increased (P < 0.05) amounts of available leucine, isoleucine, histidine, and valine. Amount of available lysine was reduced (P < 0.05) by 11.8 g kg−1 initial lysine. Nylon bag results with steers indicated that 15 min heat treatment maximized the (P < 0.05) small intestinal disappearance of all the individual essential AA and, also, increased amounts of available AA. Supplementation of the 15 min moist heated CM with lysine would be required for CM intended for poultry.