The present invention relates to compositions of low molecular mass arabinoxylans for use as dietary supplements and to methods of improving growth performance and feed utilization of animals through the supplementation of their diets with the said compositions. In a preferred embodiment, the low molecular mass arabinoxylans are derived from natural sources, such as plant material and more preferably of cereals. They can be selected fractions of said natural arabinoxylans or can be obtained by acid and/or enzymatic depolymerization or fragmentation of said natural arabinoxylans or they can be structural analogues produced by chemical and/or physical processes.
