Table 14.
Multiple regression analyses to find the important protein structural variables for predicting energy values of canola meal
| Predicted Variables (Y) | Variable (s) Selection (Variables Left in the Model with p < 0.05) | Prediction Equation Test Model: Y = a + b1 × x1+ b2 × x2… | R2 Value | * RSD | p Value |
|---|---|---|---|---|---|
| Digestible nutrients % of DM | |||||
| ** td NDF | *** Ratio left in the model | td NDF = −4.28 + 9.62 × Ratio | 0.31 | 0.65 | 0.001 |
| td NFC | AII and Ratio left in the model | td NFC = 48.58 − 0.83 × AII − 16.50 × Ratio | 0.47 | 0.89 | <0.001 |
| td CP | Ratio left in the model | td CP = 29.40 + 11.60 × Ratio | 0.34 | 0.74 | 0.001 |
| TDN 1X | Area left in the model | TDN 1X = 55.82 + 2.83 × Area | 0.14 | 0.94 | 0.040 |
| TDN p 3X | Area left in the model | TDN p 3X = 51.27 + 2.60 × Area | 0.14 | 0.87 | 0.040 |
| Energy values (Mcal/kg DM) | |||||
| DE 1x | Height left in the model | DE 1x = 2.90 + 0.19 × Height | 0.20 | 0.05 | 0.014 |
| DE p 3x | Height left in the model | DE p 3x = 2.67 + 0.17 × Height | 0.19 | 0.05 | 0.016 |
| ME p 3x | Height left in the model | ME p 3x = 2.25 + 0.17 × Height | 0.19 | 0.05 | 0.016 |
| NEL p 3x | Height left in the model | NEL p 3x = 1.39 + 0.12 × Height | 0.19 | 0.03 | 0.017 |
| ME 3x | Height left in the model | ME 3x = 2.38 + 0.15 × Height | 0.19 | 0.03 | 0.017 |
| NE m3x | Height left in the model | NE m3x = 1.51 + 0.13 × Height | 0.18 | 0.03 | 0.018 |
| NE g 3x | Height left in the model | NE g 3x = 0.92 + 0.11 × Height | 0.19 | 0.03 | 0.017 |
| DE p 4x | Height left in the model | DE p 4x = 2.55 + 0.16 × Height | 0.19 | 0.05 | 0.016 |
| ME p 4x | Height left in the model | ME p 4x = 2.12 + 0.17 × Height | 0.19 | 0.05 | 0.015 |
| NEL p 4x | Height left in the model | NEL p 4x = 1.31 + 0.11 × Height | 0.18 | 0.03 | 0.020 |
Notes: * RSD, residual standard deviation. ** td NDF, truly digestible neutral detergent fiber; td NFC, truly digestible non-fiber carbohydrate; td CP, truly digestible crude protein; TDN 1x, total digestible nutrients at one times maintenance; TDN p 3x, total digestible nutrients at productive level of intake at three times maintenance; DE 1x, digestible energy at one times maintenance; DE p 3x, digestible energy at a productive level of intake (3x maintenance); ME p 3x, metabolizable energy at production level of intake (3x maintenance); NEL p 3x, net energy for lactation at productive level (3x maintenance); ME 3x, metabolizable energy; NE m 3x, net energy for maintenance; NE g 3x, net energy for gain. *** Protein structural spectral parameters; Height, Height ratios of amide I and II; AII, Amide II area; Ratio, Ratio α-helix: β-sheet; Area, Area ratios of amide I and II.