Use of α-1,6-galactosidase and β-1,4-mannanase improves the ileal digestibility of energy and amino acids in pig diets

Soybean meal is a major protein source for swine and other monogastric animals. However, soybeans, like other legume seeds, contain anti-nutritional factors. Scientists have been successful in eliminating the principle growth inhibitors in soybeans through physical and chemical processing. However, galactosyl oligosaccharides, i.e., α-galactosides and βgalactomannan, known as flatulence-producing factors are still present in soybean meal produced by conventional processes (Rackis, 1981). The content of α-galactosides (raffinose, 1.0% and stachyose, 4.6%) and β-galactomannan (1.2%) is relatively high in soybean meals and these αgalactosides and β-galactomannan are not digestible by pigs and other monogastric animals because of the lack of nzymes that target α-1,6and β-1,4-galactosyl bonds. Consequently, the levels of indigestible galactosyl oligosaccharides are negatively related to energy and protein digestibility and growth in swine (Veldman et al., 1993; Gdala et al., 1997) and poultry (Coon et al., 1990).