Layer Management: Reaching and Holding Peak Production

A well-managed commercial layer flock peaks above 92% production around week 28–30 and holds over 90% for several months. Flocks that peak low almost always did so because of something that happened during rearing, before the first egg.

Rearing decides the peak

The single most predictive number is body weight at point of lay. A pullet that is under target at 16–18 weeks has not built the frame or the reserves to sustain peak output, and no amount of layer ration afterwards fully compensates.

• Weigh a sample fortnightly through rearing and compare against the breed standard, not against last flock.
• Track uniformity, not just average. A flock at target average but with wide spread comes into lay unevenly and peaks poorly. Aim for 80%+ of birds within ±10% of the mean.
• If the flock is behind, delay light stimulation rather than forcing birds into lay underweight.

Lighting

Light triggers sexual maturity. The rule through rearing is never to increase day length; the rule in lay is never to decrease it.

• Begin light stimulation at 16–18 weeks, when body weight is on target.
• Increase by 30–60 minutes per week to a maximum of about 16 hours.
• Hold that day length steady through the laying cycle. Any reduction triggers a production drop.
• Keep intensity even across the shed. Dark corners mean birds that never come into full lay.

Calcium and shell quality

A hen deposits roughly 2 g of calcium into each shell — a large fraction of her total body calcium, every day.

• Raise dietary calcium to about 3.5–4.5% at the onset of lay, and further as the flock ages.
• Provide part of the calcium as coarse limestone or oyster shell, not all as fine powder. Coarse particles stay in the gizzard and release calcium overnight, which is when the shell is actually formed.
• Feed the larger calcium portion in the afternoon, matching the timing of shell deposition.
• Maintain vitamin D3 — calcium without D3 is poorly absorbed.
• Shell quality declines naturally with flock age; a sudden decline instead signals disease, heat stress or a feed problem.

Heat stress

Above roughly 30°C, feed intake falls and with it calcium and protein intake. Panting also changes blood chemistry in a way that directly worsens shell formation.

• Feed during the cooler parts of the day; many farms shift the main feeding to late afternoon and night in summer.
• Ensure cool, plentiful water — intake rises sharply with temperature.
• Improve air movement before considering anything else; ventilation is cheaper than most alternatives.
• Raise nutrient density so the bird gets what it needs from less feed, rather than expecting it to eat more.
• Consider electrolytes and vitamin C during heat waves.

Weekly numbers worth tracking

A production drop with feed intake already falling points to disease or heat. A production drop with feed intake steady points to lighting, calcium or a nutritional imbalance. The pair together diagnoses more than either alone.