The differential response of supplementary xylanase to wheat versus wheat DDGS diets indicates that the specific xylanase activity used in the present study matches the arabinoxylans in wheat, but not in the wheat DDGS. As a note of caution, the digestible lysine content of wheat DDGS from an oldstyle ethanol plant that was studied in the present study may not reflect wheat DDGS produced in new generation ethanol plants. Further studies are required to
assess the impact of improved DDGS production methods on nutrient digestibility of wheat DDGS in swine, to improve nutrient digestibility in pigs fed diets containing wheat DDGS, or to identify factors associated with reduced nutrient digestibility of wheat DDGS.