Xu et al. (2002) also demonstrated that supplementation of diets with 4 and 6 g/kg fructooligosaccharides improved ADG and G:F in growing pigs. On the other hand, several studies reported little or no effect of fructooligosaccharides on growth performance of pigs (Farnworth et al., 1992; Orban et al., 1997; Houdijk et al., 1998).