Low protein diets

I have been often asked whether pig formulas should be formulated with the minimum or maximum crude protein concentration possible. Assuming cost is about the same, I have always favoured low-protein diets. Nevertheless, this should not be taken as a universal statement, because there are conditions, mainly economical, under which a low-protein diet is not profitable. But, let’s see first, why low-protein diets are beneficial from a biological point of view and how this translates into mor