Understanding the natural laying cycle

In brief. A hen does not produce an egg to a perfectly regular clock. Age, genetics, light, feed, health, climate and moult all shape the laying curve. Understanding that cycle prevents two common mistakes: expecting the same output every day and blaming every decline on one cause.

From pullet to layer

The onset of lay is gradual. In the systems described by an FAO egg-production guide, birds often start around twenty to twenty-one weeks, with variation by strain and management. Early eggs are usually smaller, and a whole flock does not start on the same day. An age reference is therefore not a production guarantee.

Rearing prepares the laying period. Body weight below or above the intended curve, inappropriate feeding and inconsistent lighting can affect the transition. The farm should compare its flock with the breeder’s information while using advice from its nutritionist and veterinarian.

Why egg production follows a curve

After the first eggs, the proportion of hens laying rises to a peak and then normally declines with age. FAO material describes a typical cycle while emphasising the influence of breed, mortality, diet, body weight, housing and lighting. A flock average does not mean that the same hen lays on every calendar day. Egg formation takes time and the individual rhythm can shift.

Management follows hen-day production, but also total egg mass, sizes and shell quality. Egg size may rise with flock age while egg number falls. Reading only one indicator can conceal a meaningful change.

Light is a biological signal, not a replacement for care

Day length affects sexual maturity and laying. A lighting programme should maintain a stable 24-hour rhythm and an uninterrupted dark period. The UK code also recommends, where possible, a twilight phase so hens can reach perches without a sudden blackout. Abruptly extending light to “force” output can create problems; programmes must suit the strain and age.

Natural light changes with the season. In open-sided housing, it combines with artificial light. Distribution and intensity matter as well as duration, because dark, dazzling or uneven zones influence movement and access to resources.

Feed, water, heat and health alter the pattern

Egg formation requires nutrients and water. Heat can reduce feed intake, while restricted water flow or an unsuitable ration can affect egg number, weight or shell. The same changes can also result from disease or equipment failure. Diagnosis uses observation, the historic record and, when indicated, sampling or laboratory tests.

Heat stress often involves panting and reduced feeding. Housing, airflow and water are prepared before the hot season. Nutrition interventions should not be improvised.

Moult and biological rest

Moult is the renewal of feathers and may coincide with lower or stopped production. Its expression depends on age, season, light and strain. A drop should not automatically be called moult: loss of water, health problems, stress and a feed error need to be ruled out. Any deliberate moult programme must comply with animal-welfare requirements and receive qualified oversight.

What the farm records

A useful daily sheet includes birds present, eggs, rejects, weight or size, water, feed, temperature, mortality and interventions. Comparison with the previous week and the expected flock curve is more informative than an absolute target. A persistent deviation, sudden fall or clinical sign triggers investigation.

The record also notes changes in feed batch, lighting, equipment and weather. That timeline helps avoid attributing a decline to the most recent assumption rather than the evidence.

How to investigate a change in the curve

The first check confirms that the number is real: complete collection, correct flock count and functioning scale or counter. The team then reviews water and feed trends, temperature, light timers, recent handling, mortality and shell changes. A difference limited to one house points in a different direction from a site-wide change. These observations are shared with the veterinarian rather than converted into a treatment by guesswork.

Weekly averages can reduce normal day-to-day noise, but they should not conceal a sharp fall. The graph is annotated with feed deliveries, equipment failures and interventions. If output returns after a correction, the team still reviews whether the timing provides enough evidence; coincidence is possible.

Use forecasts responsibly

For customers, a production forecast is a planning tool, not a promise that biology cannot change. Stock buffers, honest availability checks and agreed substitutions protect the relationship. Marketing should not turn a peak figure into an annual average or imply that every hen lays daily.

One egg cannot tell the whole story

Egg size, shell colour or yolk colour cannot, on their own, reveal housing, feed or the health of a hen. Claims about origin and production need traceability. This article explains a general cycle; it does not publish Mamati’s flock curve and offers no output guarantee.