If laying hens are receiving proper management, the most common reason for reduction of lay is a reduction of light. The reproductive state of all birds is strongly regulated by the amount of light that they receive each day. If hens are to maintain a constant state of egg production, they must be subjected to at least 16 hours of light every day. This light can be provided from sunlight, artificial light sources, or a combination.

When the day length is increasing between December 21 and June 21, the birds are stimulated into an increased reproductive state, but between June 21 and December 21, the reverse occurs and the birds cease to produce eggs. These effects produce the natural breeding seasons for birds in a natural environment. The recommended rule of lighting for pullets and hens is: "Never increase light on growing birds but never decrease light on mature laying hens". Ignoring this rule may result in undesirable hens that do not lay eggs.

A good lighting program for hens requires that light be provided at:
• The proper length of time every day
• A minimum intensity
• The proper color

The recommended day length is 16-18 hours daily. The minimum light intensity is one foot-candle or sufficient light to clearly see the level of feed while standing over the feeder. The stimulatory color of light is a yellow or orange that approximates the spectrum of sunlight. Artificial light fixtures that provide excellent light for laying hens are incandescent bulbs, warm-white fluorescent tubes, and many of the halogen lights that produce a yellowish colored light.

Information courtesy of Mississippi State Extension Service