Wheat-based diets with or without wheat distiller’s dried grains with solubles
(DDGS) were tested with or without supplementary xylanase (4000 U kg
1 feed) in a 22 factorial arrangement. In eight
ileal-cannulated barrows, xylanase improved the apparent ileal digestibility of energy and threonine in wheat (PB0.05),
but not in wheat DDGS diets (P0.10). Xylanase did not affect total tract digestibility of energy or P (P0.10). In 72
grower-finisher pigs, xylanase did not increase growth performance of pigs fed either wheat or wheat DDGS (P0.10).
The differential response of supplementary xylanase to wheat versus wheat DDGS diets indicates that the arabinoxylans in
wheat DDGS did not match the specific xylanase activity.