Your choices to replace the effective fiber in fuzzy cottonseed using a by-product feed are limited. Fuzzy cottonseed has an effective NDF value of 75 to 100%. Brewers grain has a 40% effective NDF, while soyhulls, distillers grains, and beet pulp are less than 10%. A forage (such as haylage, hay, or chopped wheat straw) would be a better alternative.
Mike Hutjens, Extension Dairy Specialist, University of Illinois - Illini DairyNET