Welfare of laying hens in cages and alternative systems: environmental, physical and behavioural aspects

Abstract

There are many different characteristics of housing systems which affect the welfare of laying hens, particularly because welfare itself has many diverse aspects. When cause and effect relationships between systems and welfare are assessed, it is evident that no system currently under consideration is ideal. Of those priorities listed by UK authorities such as the Ministry for Agriculture, Fisheries and Food and the Farm Animal Welfare Council, all systems are likely to provide ‘freedom from hunger and thirst, adequate lighting and the company of conspecifics'. However, conventional cages are less likely than other systems to provide ‘freedom of movement, freedom from fear, comfort and shelter, suitable flooring and freedom to display most normal patterns of behaviour'. Alternative systems, though, often expose birds to the danger of disease, to aggression from dominant birds and to the risk of cannibalism or beak trimming to avoid it. Overall, welfare is compromised more in conventional cages than in well-run alternative systems, though welfare is more sensitive to poor management and to market forces in the latter. Problems in cages are also less likely to be alleviated by genetic selection than those in alternative systems. The ideal system for present-day stocks should combine the small group sizes found in cages with the freedom of movement and complex environment characteristic of alternative systems.

Keywords::

• Behaviour
• cages
• environment
• laying fowl
• systems
• welfare