Basically all egg producers who wish to give their hens access to the outdoors year-round or who are obliged to do so under the RAUS programme (established by the Swiss Ordinance on regular outdoor management of livestock) experience difficulties during prolonged rainy periods, especially outside of the growing season.
Grass does not grow back outside of the growing season which means that the birds cause lasting pasture damage in the vicinity of their housing. Many egg producers have therefore for some time experimented with open yards as an alternative to pasture runs during winter and periods of inclement weather. Open yards are well suited to providing hens regular outdoor access outside of the growing season while protecting pasture surfaces from damage. Moreover, faeces accumulating close to the birds’ housing can easily be removed from open yards by removing the top litter layer. This also reduces nutrient and parasite burdens in the vicinity of the birds’ housing and thus mitigates two significant problems arising in free-range poultry systems.
The RAUS programme does not as yet contain clear specifications for the sizes of open yards, suitable litter, litter depth and litter management. While there are many poultry keepers who have practical experience in this respect, their knowledge – in some instances based on many years of experience – has never been utilized. There are a range of studies on the suitability of different types of litter (Aviforum 2005-06), on the impact of a woodchip-covered forecourt on nutrient burden, grass cover and parasite burden (FiBL 2013), and on the effects of litter and range management on worm burden in laying hens (FiBL 2005-08). However, the results of these studies have never been brought together with a view to drawing up optimum design specifications for open poultry yards. Moreover, the issues of cost and labour requirements as well the question of how to reduce disease pressure and nutrient leaching have not yet been fully addressed.
The project aims at drawing up tangible recommendations for the design and management of open poultry yards in order to support both egg producers and implementing authorities in the credible implementation of RAUS programme specifications. To this end we will record and evaluate (1) laws and regulations governing the prevention of water pollution as well planning and construction, and (2) experiences made by commercial farmers. The results will be published in scientific journals and also in accessible form in an information leaflet for practitioners. The recommendations will also address as yet unanswered questions as to the legal situation as well as on cost and labour requirements. Such open questions will be (3) investigated in realistic field trials.
