4Davis M E,Maxwell C V,Brown D C,et al.Effect of dietary mannan oligosaccharides and pharmacological additions of copper sulfate on growth performance and immunocompetence of weanling and growing/finishing pigs.J.Anim.Sci.,2002(80):2887-2894.
5Lemieux F M,Southern L L and Bidner T D.Effect of mannan oligosaccharides on growth performance of weanling pigs.J.Anim.Sci.,2002(80):2482-2487.