Abstract: A method of promoting growth of a great number of livestock individuals to the prescribed average weight in a substantially closed house, within a reduced period of time and consumption of feed, at an enhanced rate of survival and at a suppressed degree of variation in the individual growth, which comprises heating the house floor from below and controlling the floor temperature to be substantially constant throughout the floor area, and effecting ventilation across the house substantially without generation of any noise by delivering outdoor air taken in through an intake opening substantially evenly into the house and discharging the air within the house by natural exhaust through an exhaust window. A livestock house for practice of the method is also disclosed.

Abstract: A planar heating element having a thin flat body formed from an insulating thermoplastic resin and electrically conductive powder. The electrically conductive powder is formed in a layer within the thermoplastic resin in the neighborhood of the entire surface of the body. Lead wires within the flat body being positioned near the surface of the body such that the lead wires are electrically connected to said layer of electrically conductive powder. The planar heating element being produced by a method comprising melt-admixing an insulating thermoplastic resin with an electrically conductive powder. The mixture is then extruded, and the extruded body is rapidly cooled.

Abstract: The present invention is related to a method for producing a planar heating element. The method comprises melt-admixing an insulating thermoplastic resin with an electrically conductive powder. The mixture is then extruded, and the extruded body is rapidly cooled.