The new cages provide more living space per hen, 750 cm2 cage area per hen compared to 550 cm2 in conventional battery cages.
Production percentage (daily eggs per hen) climbs rapidly to a peak of 80-85% at 29-32 weeks, and then gradually declines with age.
The union's rules say that the chicken cages must allow at least 750 square centimeters per hen and contain a nest, litter, perch and "clawing board."
In 1900, average egg production was 83 eggs per hen per year.
There is a minimum of 4 m2 of outdoor space per hen.
Floor space ranges upwards from 300 cm per hen.
EU standards in 2003 called for at least 550 cm per hen.
It is known for its high egg production of approximately 300 eggs per hen in the first year of laying.
That said, it is important to stress that adapting to the directive is quite burdensome for the sector's companies: 30% per hen in Portugal.
In systems other than cages, however, the space per hen can be reduced.