The invention relates to an apparatus for and method of steam treatment of fodder, for example animal fodder which is typically in baled form (10). The purpose of steam treating is to kill mesophilic and thermophilic mould spores that are either attached to the fodder or detach when disturbed and become airborne. These airborne particles are associated with respiratory problems, infections and allergies to livestock as well as humans. The present invention provides an apparatus for steam treating fodder comprising at least one steam distribution manifold (1), which has a plurality of lances (2a, d, c) adapted to penetrate a bale of fodder (10) so that steam is supplied to the interior volume of the fodder.