Donkoh et al., 2009. Livest. Res. Rural Dev., 21 (3)

A range of Ghanaian poultry feedstuffs were evaluated for their nutrient quality. The samples were subjected to chemical analysis to obtain gross composition and apparent metabolizable energy (AME) data and also to ileal digestibility bioassay, using broiler chickens, to determine the digestibility of each of the amino acids (AA) in each of the samples of feedstuffs under evaluation. For the cereals (maize, sorghum I and sorghum II) and cereal by-products (wheat bran, rice bran, maize bran and dried brewer’s spent grains), differences in crude protein, crude fibre and crude fat contents as well as AME and ileal digestibility of protein and amino acids were observed. The mean tannin content of low tannin sorghum (sorghum I) was determined to be 0.38%, while the corresponding value for high tannin sorghum (sorghum II) was 1.87%. Tannin content affected AME and ileal AA digestibility negatively. For the high protein feedstuffs (fishmeal I, fishmeal II, blood meal, soyabean meal and cotton seed cake), differences were also observed among feedstuffs with respect to crude protein, fat, AME and ileal protein and AA digestibilities. Amino acids contained in blood meal are well digested by broiler chickens than amino acids contained in the other high protein feedstuffs. The fishmeal samples show a wide variation in gross compositional values, AME contents and AA digestibility coefficients. It is concluded that the digestibility of amino acids varies greatly among different feedstuffs, thus the use of digestible values rather than tabulated gross compositional values should improve the precision of dietary formulation.