The poultry birds which are raised for egg production are called layer poultry. Commercial hen generally starts laying eggs at the age of 12-20 weeks. They start laying eggs regularly at their 25 weeks of age. After 70-72 weeks of age egg production of layer poultry get reduced. For commercial layer poultry farming, producers generally keep the hens for 12 months from their first laying period. And then sell them for slaughter purpose. Although chickens naturally survive for more than 6 years. For re-invigorating egg laying, the hens are force moulted in some countries. For commercial egg laying poultry farming systems, the environmental conditions are often automatically controlled by the producers. For a simple example, presence of light helps the bird for laying eggs earlier.
So, the producers should provide more lightening period to increase the probability of beginning laying eggs. The egg-laying birds lays more eggs in warmer months than the cold months. So, keeping the temperature of the room moderate will be very helpful for better egg production. Some commercial egg laying chicken breeds can produce more than 300 eggs a year. Layer poultry are raised in various methods. The common and most popular layer poultry farming systems are described shortly below.