the process of a chicken laying eggs

Hens may live in backyard flocks for 6-8 years, and most flocks will produce eggs for 3-4 years. The level of egg production, egg size, and shell quality decrease each year. Most commercial layers are kept for 2-3 years as their egg production decreases after this time. To keep a small flock producing, owners should plan to retire old hens and add young hens (pullets) every 2-3 years.