A major goal of many poultry producers is to attain good flock liveability. Historically, most poultry producers have manipulated environmental conditions and management to maximize bird health. In the past two decades there has been much research into nutritional regimes that improve bird health through immunomodulation. Commercial poultry environments contain ubiquitous micro-organisms that continuously challenge the immune system. Nutritional supplements that enhance immune system function may improve flock performance and be economically advantageous. This paper reviews the literature on zinc-methionine and the avian cellular immune system. Current knowledge of the effects of zinc on many animal models is reviewed and a hypothetical mechanism for the action of zinc-methionine on this system is discussed.
