BEAK TRIMMING OF POULTRY - ITS IMPLICATIONS FOR WELFARE

摘要

Beak trimming remains a controversial subject. It has undoubted economic advantages for the producer, in particular by reducing the incidence of cannibalism and feather pecking, but the procedure is traumatic for the bird and deprives it of important sensory feedback from its beak. It can have harmful neuroanatomical consequences: although the tissue damage is repaired the sensory receptors are not replaced, neuromas may form and become a source of chronic pain. The danger of neuroma formation is reduced and may be absent if the procedure is performed only in young birds. Beak trimming results in both immediate and more persistent effects on behaviour, food intake and body weight. Trimmed birds are generally less active, show less behaviour involving pecking, eat less and grow more slowly than controls. These changes are primarily a consequence of the sensory deprivation. In caged medium hybrid layers and growing broilers beak trimming is difficult to justify, whereas the incidence of pecking damage is so high in light hybrids in multi-bird cages at high stocking densities that beak trimming is universal. A case can also be made for its continuation, on welfare as well as on production grounds, in floor-housed flocks of laying fowl and breeding turkeys. In these contexts it reduces mortality by inhibiting feather pecking, cannibalism and, possibly, aggressive pecking. In the long term beak trimming should be phased out and undesirable behaviour controlled by environmental means and by increased effort being devoted to the genetic selection of commercial stocks which do not engage in damaging pecking, either in cages or when floor-housed in large flocks.