Illuminance and egg production in broiler breeders

Area of Science:

• Poultry Science
• Animal Husbandry
• Avian Biology

Background:

• Lighting programs significantly influence poultry productivity and welfare.
• Understanding optimal illuminance levels is crucial for maximizing egg production in broiler breeders.
• Current industry standards for lighting may not reflect the biological optima for all production systems.

Purpose of the Study:

• To investigate the effects of different illuminance levels during rearing and laying periods on Ross broiler breeder performance.
• To determine the biological optimum light intensity for broiler breeder egg production.
• To compare industry recommendations with empirically derived optimal lighting conditions.

Main Methods:

• Broiler breeders were reared under 15, 20, or 45 lux and transferred to 25, 55, or 70 lux at 20 weeks.
• Performance metrics including egg numbers, rate of lay, egg mass, and liveability were recorded.
• Meta-analyses were conducted on current and historical data to identify biological optima.

Main Results:

• No significant interactions were found between rearing and laying illuminance levels.
• Meta-analyses indicated biological optima of 15 lux for rearing and 7 lux for laying.
• Higher rearing illuminance (45 lux) resulted in lower egg weight and earlier sexual maturity.
• Lower laying illuminance (25 lux) increased floor eggs compared to 55 or 70 lux.

Conclusions:

• The biological optimum for laying hens is 7 lux, which differs from typical industry recommendations.
• While 10-20 lux (rearing) and 30-60 lux (laying) are suitable for floor-housed birds, 7 lux may be appropriate for caged systems.
• Adjusting illuminance based on biological optima, rather than solely on industry standards, can enhance broiler breeder productivity and welfare.