Among by-products, soybean hulls, despite their high NDF concentration, are characterized by a high energy value, and they can thus represent an important energy source for dairy cattle. Ipharraguerre et al. (2002b) showed that soybean hulls can replace corn to supply up to 30% DM of TMR for mid-lactating cows. The replacement of corn meal by soybean hulls decreases dietary starch concentration and increases the NDF concentration.