Enzyme supplementation of diets containing high levels of grain legumes - a review

Increased levels of indigestible carbohydrates, such as α-galactoside oligo saccharides and non-starch polysaccharides (NSPs), limit the inclusion rate of grain legumes in diets for pigs and poultry. There is contradictory information available on the anti-nutritive effects of legume NSPs and the effects of feed enzymes on legume NSPs. The addition of carbohydrases to diets containing high levels of soybean meal (SBM) as the main protein source has a significant effect on ileal protein digestibility and ileal NSP concentrations. However, the overall effect on broiler performance remains controversial. Similarly, the addition of carbohydrases to lupin-based diets has been shown to alter the intestinal NSP concentrations in comparison to unsupplemented diets. The overall effects on weight gain, feed intake and FCR, however, varied from study to study.