Nutritive value of some tropical feedstuffs for pigs. Chemical composition, digestibility and metabolizable energy content

Abstract The chemical composition of some tropical feedstuffs and digestion coefficients obtained using pigs are given. Considerable variation was found in both chemical composition and content of metabolizable energy (ME) within some by-products, i.e. maize hominy feed, wheat bran, sun-flower cake, cottonseed cake. On average for all feedstuffs a 2.2% decrease in digestibility of energy for each 1% increase in crude fibre was found ( R 2 = 0.73). Dry matter digestibility (DMD) is highly correlated with ME (or digestible energy) content and hence where DMD can be determined, the ME content can be predicted with reasonable accuracy for practical purposes ( R 2 = 0.83). Use of table values for the gross energy content of the feedstuff and DMD showed a promising equation with a R 2 = 0.94 and residual standard deviation of 0.60 MJ or 4.1% of the average value. Inclusion of up to four chemical components (crude protein, crude fat, crude fibre and soluble carbohydrate) did not result in a better prediction equation than that obtained by using DMD or using table values.