In the last half century, significant increases in the productivity of modern poultry stocks have been achieved for both the meat and the egg production sectors of the global poultry industry. Synergies have resulted from advances made in all the major ac- tivities of poultry management and housing, nutrition and ration formulation, applying poultry genetics knowledge in commercial breeding programmes and better diagnosis and control of avian diseases. Of all these core elements, poultry health and disease can be the least predictable. Although poultry diseases from nutritional and metabolic caus- es can be of concern, the emphasis in this information note is on.