In vitro DM digestibility (IVDMD) was calculated in the dried ground samples according to the two-stage technique ofTilley and Terry (1963), using rumen fluid obtained from two ruminally fistulated dry Holstein cows, each sample in fourreplicates. The rumen fluid donor-cows were fed 7 kg (DM) of wheat hay and 3 kg (DM) of total mixed ration (TMR) comprisedof 300 g/kg grains, 350 g/kg wheat silage, 150 g/kg soybean meal, and 200 g/kg by-products (cottonseed, wheat bran, andgluten feed).