Key biological characteristics of commercial layer breeds include a lightweight body frame (1.4–1.8 kg) that minimizes feed maintenance costs, an active immune metabolism, and a highly efficient reproductive system capable of producing one egg approximately every 24–26 hours at peak production.

The global commercial egg industry is dominated by a small number of hybrid layer strains:

• Lohmann Brown (LB-Lite): The world's most widely farmed brown egg layer. Target of 305–315 eggs per hen housed (HH), with egg weights of 62–65g at peak. Explore full performance data in the Lohmann Brown Performance Guide.
• Hy-Line W-36: The dominant white egg layer globally. Small body size (1.35 kg) and extraordinary feed efficiency. Produces 295–310 eggs per hen over 72 weeks.
• ISA Brown: A popular brown egg hybrid noted for docility and robustness in hot climates.
• Bovans Brown: Hardy dual-purpose tendency, performing well under non-cage enriched conditions.

Egg production performance is tracked by two essential metrics:

• Hen-Day Production (HDP%): The percentage of eggs produced daily relative to the number of hens alive on that day. Formula: (Eggs Laid ÷ Hens Alive) × 100. Peak HDP% for commercial layers is 92–96% at 24–28 weeks of age.
• Hen-Housed Production (HHP%): Total eggs produced from day-of-lay to the end of the laying cycle divided by the number of hens placed. This accounts for cumulative mortality and is a better profitability measure.

Track your flock's weekly production curve against breed standards using our Hen-Day Production Calculator.

Layer hen nutrition changes significantly across the production cycle:

• Pre-Layer (Weeks 15–17): Transition phase. Feed calcium gradually from 1.0% to 3.8% to stimulate medullary bone calcium storage before first egg.
• Peak Layer (Weeks 18–45): Maximum protein requirements (17–18% CP). Calcium at 4.0–4.2% to support daily eggshell calcification. Digestible lysine at 800–900 mg/hen/day.
• Late Layer (Weeks 46–72): Slightly reduced protein needs. Calcium raised to 4.3–4.5% as shell gland efficiency declines. Feed coarse limestone particles (2–4 mm) for overnight shell deposition.

Formulate precise layer feed rations using our Least-Cost Feed Formulation Mixer.

The major commercial laying hen housing systems differ in welfare, cost, and production efficiency:

• Conventional (Battery) Cages: 450–550 cm² per bird. High egg collection efficiency and low disease risk, but banned in the EU since 2012.
• Enriched (Furnished) Cages: Minimum 750 cm² per bird with perches, nesting space, and scratching mat. EU-compliant standard.
• Aviary (Cage-Free) Systems: Multi-tier litter-floor systems providing perching, scratching, and nesting freedom. Higher welfare but requires more management skill.
• Free-Range: Access to outdoor pastures. Commands premium egg prices. Stocking density limited to 9 hens/m² indoors.