Effect of grain processing on in sacco digestibility and degradability in the rumen.

Effect on nylon-bag digestibility of rolling and steam-flaking as such or followed by grinding through a 1-mm screen was studied in wheat, barley and maize grains. Digestibilities of ground grains were not different, irrespective of rolling or steam-flaking, except flaked and ground barley, which was less digestible than ground barley. Rolled and flaked grains were less digestible than ground grains, except for rolled wheat which was not different from ground wheat. These results suggest that particle size due to grinding is more important than other methods of processing. Dry matter and protein degradabilities of steam-flaked grains were investigated by in sacco technique and compared with unprocessed grains. Dry matter degradability during incubation periods up to 24 h was reduced for steam-flaked wheat and barley, but increased for flaked maize. Protein degradability was lower for flaked grains.