Amino acid digestibility and metabolizable energy in a heating doublelow rapeseed meal fed to pigs

Two experiments were conducted to test the hypothesis that both the degree and duration of heatingthat is applied will affect the concentration of metabolizable energy (ME) and the standardized ileal digestibility (SID) of amino acids (AA) in double-low rapeseed meal (RSM) fed to growing pigs. Nine treatments were prepared using a conventional RSM that was either not autoclaved or autoclaved following one of 8 treatments: 110 °C for 15 or 30 min or 150 °C for 3, 6, 9, 12, 15, or 18 min. In both experiments, 20 barrows were assigned to a replicated 10 treatment × 4 period Youden square design. There were no effects of autoclaving at 110 °C on ME or on SID of AA in RSM but both ME and SID of AA in RSM were less (P<0.01) if RSM was autoclaved at 150 °C compared with 110 °C. At 150 °C, there were decreases (quadratic, P<0.05) in both ME and SID of AA as heating time increased. In conclusion, autoclaving at 110 °C did not affect ME or SID of AA in double-low RSM, but autoclaving at 150 °C reduced both ME and SID of AA, and the negative effects increased as heating time increased.