Domestic Chicken

The chicken, Gallus gallus or G. dometicus is a domestic fowl, probably the most common bird in the world. It is raised for meat, eggs, and by products such as feathers; for sport; and as a hobby. Developed chiefly from the red jungle fowl (G. gallus) of Southeast Asia, the chicken has been fully domesticated for at least 4,000 years. Chicken were kept for their eggs, and when the birds grew too old to lay, they were used for meat. The development of different breeds of chickens either for egg laying or for meat production, the transfer of farming operations indoors were the environment can be controlled, and the use of sophisticated mass production techniques led to the modernization of the chicken industry.

Most chicken range in weight from 3 to 4.5 kg (7 to 10 lb), with the large breeds reaching about 6 kg (13 lb) and some bantams only 670 g (1.5 lb). Hens start laying at 22 weeks of age. During the hen’s most productive period, an egg may laid about every other day for most of the year. Eggs hatch in 21 days. Domestic chicken for consumption may just age 2 to 3 months being sold to consume.

The chicken is most widespread of all domestic fowl. Popular types are the Cornish, a deep-breasted Enlish breed grown for its meat, and the Leghorn, a Mediterranean breed that is the world’s leading egg producers.