pit therebelow not shown tubular fluid passage 19 is provided in slats 15 to receive heated or cooled fluid from a conventional heat exchanger 28 and through manifolds 12 and 13 slats 15 are assembled into laterally adjacent and parallel planar series to form a floor panel by placing slats in a jig which positions slats 15 as shown fig1 then a mold is placed over slats 15 to allow the adhesive to be molded therein and around the slats fig3 tension bands 17 are then placed therearound to further return slats 15 in position on adhesive 16 as it becomes hard slats 15 can be made of extruded thermoplastic material such as polyvinylchloride polystyrene or abs graft copolymer or acrylonitrille butadiene and styrene or a resin and fiberglas build up other and suitable extrudable materials such as for example aluminum may be employed in fabricating slats 15 however the preferred material for slats 15 is wound fiberglas filament 15a and resin 15b whereby the inside passage surfaces of slats 15 are smooth and the outer upper floor surface 25 has ridges 25a and recesses 25b these ridges 25a and recesses 25b of surface 25 of slats provide a surface which will not tend to form puddles and which will drain regularly as the floor is used by livestock also surface 25 is slightly crowned or domed laterally not shown in detail so that waste fluids will tend to run off laterally as a result of the ridges and grooves and slight crown in slats 15 slats tend to drain regularly and thereby present a.