Abstract
The housing and management of laying hens and their productivity has gone through enormous developments in the last century. Housing has changed from free-range systems, via battery cages to a variety of loose housing and different types of battery cages, and back to outdoor access systems. Although battery cages are still the main system used worldwide, the number of hens housed in aviaries and free-range systems has increased in Europe, Australasia and some parts of the USA, but aviaries and free-range systems are still considered a niche sector compared to caged housing. The following paper reviews how breeding and selection have responded to changes in housing and management and whether different types of housing require different breeding programmes and, more specifically, whether a dedicated breeding programme should be developed for aviary and free-range systems.
From the available literature it was concluded that broadening the selection goal in existing lines is the best option for breeding programmes to provide genotypes that are suitable for a range of housing systems.
Acknowledgements
The authors gratefully acknowledge co-funding from the European Commission, under the Seventh Framework Programme for Research and Technological Development, for the Collaborative Project LowInputBreeds (Grant agreement No 222623).
The work of Wageningen LR was partly funded by the Dutch Ministry of Economic Affairs.