A polynomial regression analysis was used to predict the effect of the inclusion of various levels of canola meal in the diet on the parameters of growth performance, nutrient digestibility, and intestinal villus morphometry.Data were analyzed using the GLM procedure
of the SAS program (SAS, 2002); the polynomial regression models were selected based on the significance of the regression coefficients (P < 0.05) and on the value of the coefficient of determination. The maximum of the curve corresponding to the quadratic effect was then calculated for the observed variables.