As poultry production is a prime example of a vertically integrated agricultural industry, with intensive rearing systems of birds of efficient feed conversion ratios and products of handy size and ready marketability, it is not surprising that it is currently showing the strongest growth in output of any category of meat. World-wide, it is a huge industry. Estimates of poultry populations are detailed in Table 1. The largest increase in poultry populations between 1979 and 1989 are in N&C America, S America & Asia. As a general rule, poultry populations in developing countries are rising at a faster rate than in developed countries.