A poultry treatment apparatus is disclosed herein. In various aspects, the poultry treatment apparatus may include a tank forming a reservoir at ambient pressure and containing liquid. A pump may be in fluid communication with the tank, and the pump may be in fluid communication with a liquid intake of a first nozzle, and in fluid communication with a liquid intake of a second nozzle to supply liquid under pressure from the tank to the liquid intake of the first nozzle and to the liquid intake of the second nozzle. A compressor may be in fluid communication with an air intake of the first nozzle and with an air intake of the second nozzle to supply compressed air to the air intake of the first nozzle and to the air intake of the second nozzle. In various aspects, the combination of compressed air and liquid under pressure deliver spray from the first nozzle and deliver spray from the second nozzle, and the first nozzle and the second nozzle deliver about the same flow rate of liquid with droplets of similar size. The first nozzle is secured to a boom at a first elevation to deliver spray into a first tier, and a second nozzle secured to the boom at a second elevation to deliver spray into a second tier, the second tier being at a different elevation than the first tier, in various aspects. The tank, the compressor, the pump, and the boom are attached to a cart traversable to deliver spray simultaneously to poultry contained on the first tier and poultry contained on the second tier, in various aspects.
