The digestibility of protein in low-quality roughages such as straw, corn stover, cottonseed hulls, and corncobs is quite low. In contrast, the protein digestibility of high-quality forages, grains, and oil seed meals is relatively high. The digestible protein content of some common feedstuffs is shown in the following table.
Percent Crude and Digestible Protein in Feedstuffs
Feedstuff % Crude Protein % Digestible Protein
Alfalfa hay 15.0 10.6
Barley 12.0 9.5
Brome grass hay 10.6 6.4
Corn 9.0 7.0
Cornstalks 5.0 2.0
Cottonseed hulls 3.9 0.0
Cottonseed meal 44.0 39.6
Ground cobs 2.0 0.0
Linseed meal 32.0 26.8
Oats 12.0 9.4
Sorghum 9.0 7.0
Sorghum stover 6.8 3.4
Soybean meal 44.0 39.6
Wheat 12.5 9.8