The length isn't important but the cage should not be any wider than 3-4 feet to permit easy removal of birds and for cleaning. The cages should have a solid divider every 3-4 feet to prevent the birds from piling in one end and to prevent the cocks from fighting. Individual pairing of breeders makes it possible to cull unproductive birds, results in less fighting, mortality, and egg breakage, and allows for genetic selection. This system is most expensive because more males are used. Four major environmental factors that affect breeders are light, temperature, air quality, and space.
Light stimulates the breeder's reproductive system resulting in breeding.
Providing artificial light will bring the breeders into egg production any time throughout the year. The light intensity should be about 5 foot candles. A 60 watt incandescent light at 1-ft. Never reduce the length or light intensity. When lighted, some hens will start egg production as early as 16 weeks, but most will begin between 22 and 25 weeks.