U_Stormcrow
Crossing the Road
there are a number of ways to extract both soy oil and canola oil. Some are "more palatable" than others. It can be hard to determine how yours was obtained, unless labeled by someone/some organization you trust.
@RojoMarz was kind enough to provide a link above. If you look at the chart comparing solvant extracted canola meal with expeller produced canola meal, you see that the expeller produced meal has far higher apparent metabolizable energy values - because less of the fat (oil) was extracted during the expeller process. Which is why the solvent method (hexane, I think, don't quote me) is preferred by those making canola oil - far more oil produced per unit of input.
and I am not a proponent of high fat feeds, so no general need (or particular advantage) to adding any oil to a feed, unless its being used to aid pellet formation. But then, I feed crumble....
