Raising backyard poultry (Gallus domesticus) in urban environments is a growing trend in the USA. In developing countries, backyard poultry represent ~80% of poultry stock, often consisting of indigenous unselected breeds of various ages, with various species mixed in the same flock. This serves to meet household food demands and is an additional source of income. Modern day USA backyard poultry owners often view their birds as companion animals, in contrast to poultry raised for commercial production. A 2010 USDA study in four cities (Los Angeles, Denver, Miami, New York) found that 0.8% of all households owned chickens, and nearly 4% of households without chickens planned to have chickens in the next 5 years. As backyard poultry ownership becomes increasingly popular, owners must be properly educated about how to keep their flocks healthy; thus, more veterinarians must be capable of providing this education and/or veterinary care.
All commercial and domestic chickens originate from the red jungle fowl (Gallus gallus), which was domesticated in Southeast Asia many centuries ago. Today, hundreds of different chicken breeds are bred for different purposes and are characterized by meat-type, egg-laying type, and dual purpose. Meat-type chickens are characterized by rapid growth rate and good meat yield, versus egg-laying chickens, which are selected for good egg production. Dual purpose chickens, such as Plymouth Rock, New Hampshire, Rhode Island Red, Wyandotte, and Orpington, are reasonably good for both egg and meat production, making them a suitable choice for backyard chickens for most owners.
Purchasing chicks and other poultry from a reputable hatchery or breeder is recommended to get off to a good start and prevent future problems. Purchasing from hatcheries or breeders that participate in the National Poultry Improvement Plan is recommended, because these flocks are routinely tested for diseases such as Salmonella Pullorum and S Gallinarum (see Salmonelloses). A list of certified hatcheries and breeders can be found by contacting official state poultry associations. In addition, prospective owners are encouraged to physically visit the breeder flock or hatchery of purchase to ensure only healthy birds are brought into the backyard flock.
Many backyard flock owners have multiple ages and/or species of birds. Mixing birds of different species and from different sources increases the risk of introducing disease, and it is preferable to keep only birds of similar ages and species together (“all in/all out”). If multiple ages and/or species are kept on a property, efforts should be made to minimize contact between groups by keeping them in separate locations. Birds that are either economically or emotionally most important should be cared for first each day. Separating new or returning birds for at least 4–6 weeks is necessary to monitor for signs of illness. Practicing good biosecurity is also key for good poultry health.