Darkbrooders in chicken rearing

Lead Institute OL Institute of Organic Farming

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Use of darkened heating plates ("dark brooders") in the rearing of chicken and effect on behavior and animal welfare during rearing and the subsequent fattening and laying period

The living conditions of animals in the early phase of life have a considerable influence on behavioral development. Chicks raised by a mother hen are less anxious and show a higher degree of behavioural synchronization than chicks raised artificially, which can reduce featherpecking.

Background and Objective

Hens provide the chicks with security, warmth and guidance regarding social, feeding and other behavior. The majority of chicks in both conventional and organic farming are artificially hatched in incubators and reared in age-homogeneous groups without hens.Some aspects of maternal care can be provided artificially with the aim of improving the behavioral development of the chicks. One example of this is the use of dark brooders (DB) in rearing. These are electronic heating plates that are darkened at the sides. Like the mother hen, dark brooders offer the chicks a dark and warm environment in which to rest. The use of dark brooders can reduce the incidence of feather pecking and cannibalism by synchronizing the animals' behaviour, resulting in lower mortality and better plumage and skin condition.

The aim of the planned project is to test the use of simple and cost-effective DB in the starter phase (up to the end of the 6th week of life) in organic chick rearing with regard to effects on animal behavior and animal welfare as well as practicability (working hours) and economic aspects (energy costs) under organic practice conditions.

Approach

The planned project comprises four work packages with a total project duration of 24 months. The project will start on January 1, 2025. In April 2025 and 2026, respectively, day-old chicks of a laying hen origin commonly used in organic farming will be housed on the experimental farm of the Thünen Institute of Organic Farming in Trenthorst-Wulmenau. After a six-week starter phase, the cockerels are transferred to a practical farm for further fattening, the pullets are reared in Trenthorst until they are 16 weeks old and then kept on a practical farm for one laying period. Regular behavioral observations and animal welfare assessments are carried out throughout the entire rearing period.

Our Research Questions

Does a behavioral synchronization take place in chicks that are offered DB ?
Do chicks that are offered DB show less aggressive feather pecking ?
Do laying hens and ready-to-slaughter broiler chickens offered DB show less aggressive behavior ?
Is the stress load of the animals, which can be detected via the coricosterone content in the feathers, is lower when rearing with DB than without it ?
Does the use of DB in rearing result in lower operating costs ?