Poultry are kept all over the world for various reasons. They are one of the cheapest sources of animal protein and can be kept by anyone, even in backyards. all over the world, brown, black and white chickens are kept by large commercial farmers for chicken meat or egg production, by smaller farmers and by households in their backyards. Some very important factors that should be addressed to ensure that you have a healthy flock of chickens are management and environment. When chickens are healthy they consume less feed and produce more quality eggs. They are less trouble to look after and less money is spent on medical costs. Poultry disease can spread rapidly among chickens because they are usually kept together in the chicken house. The chickens share the same feeders and drinkers, which can spread disease and infections rapidly from sick to healthy chickens. In intensive egg production systems much focus is placed on the egg laying performance of the flock. Poultry diseases can negatively affect the health and performance of your flock. Learn more about how to diagnose chicken diseases based on the clinical signs, and how to prevent and treat disease via specific vaccination or medication.