A mat (10) for a slatted floor of an animal house has an upper surface (22) to bear the weight of an animal, a lower surface (24) for overlaying the slatted floor, and a plurality of edges (18, 20). The mat is provided with drainage channels (42) below the upper surface and leading to said edges, the drainage channels being open to said upper surface and sloping downwardly towards an edge to assist is run-off of waste from the mat. The aggregate surface area of the upper surface and drainage channels has an average slope relative to the horizontal, in use, of from 3 degrees to 13 degrees, and more preferably at least 5 degrees.
