In semi-dark houses, the artificial light intensity should be at least 10 times higher than the light
intensity coming from outside to cancel out its effect.
Midnight lighting
Midnight lighting (1hr 30 min in the middle of the dark period and running the feeders during this time)
is often used to encourage feed intake and growth at the beginning of production. If necessary, it can
be installed since transfer and then be gradually withdrawn when breeders reach their adult body
weight.
Midnight lighting is also useful during hot season to reduce the negative impact of high temperatures
by allowing the birds to eat during the cooler hours of the night.
In addition to this, midnight lighting helps to maintain a better egg shell quality by allowing the birds to
ingest calcium at the end of shell formation. This has a beneficial impact on shell quality and hence
on hatchability.
The regular lighting program (time of “lights on” and “lights off”) should not be changed when the
midnight light is added. Midnight lighting may be used throughout the flock’s life if necessary.
Production period general management
Transfer
Transfer is a major source of stress, accompanied by changes in environment (temperature, humidity,
etc.) and in equipment. It should be carried out as speedily as possible. The following points should
reduce the severity of this stress.
Age at transfer
Because of the stress to which pullets are subjected during transfer and immediately afterwards, it is
extremely important that transfer be completed before the appearance of the first eggs. Most
development of the reproductive organs (ovaries and oviduct) occurs during the 10 days prior to the
first egg being laid.
We recommend to schedule the transfer at 16 weeks of age and to make sure all hens are housed in
the production facilities by 119 days of age. Vaccinations should be given at least a week before
transfer so as to obtain a good vaccine reaction. A late transfer or a too long transfer often leads to
delayed start of lay and higher mortality and increases the risk of floor eggs.
Lighting
The duration of lighting during lay should take account of the programme used during rearing.
Giving 22 hours of light the first day and increasing light intensity for the first 4 days can help the birds
to be adapted to the new environment when drinking and feeding equipment used in rearing and
production period is different or when birds are transferred into cages. However, in case of floor
production and in dark houses, this might not be necessary.
Encouraging water consumption
Birds can become dehydrated during transfer. The water loss is between 0.3% and 0.5% per hour
according to atmospheric conditions (4 g/hr at 20°C, more than 8 g above 30°C)