Joy A. Mench
Department of Animal Science
University of California
Davis, California 95616-8532
Paul B. Siegel
Department of Animal and Poultry Sciences
Virginia Polytechnic Institute and State University
Blacksburg, Virginia 24061-0306
Cannibalism sometimes occurs in poultry, and outbreaks can result in significant injury and mortality in flocks. A common procedure to reduce the incidence of cannibalism is beak trimming, which involves removal of approximately � of the beak. Beak trimming is a part of routine husbandry for laying hens, but its use in broiler production is much less common. The beaks of male turkeys may be trimmed to reduce injuries associated with aggressive behavior.Although there are numerous publications on beak trimming, controversy exists concerning if, when, and how trimming should be performed. Studies have shown that traditional hot-blade beak trimming after 5 weeks of age can result in both acute and chronic pain (7,8,9). Precision trimmers that cut a small hole in the beak causing the tip of the beak to fall off several days later are now available; this method of beak trimming has not been thoroughly evaluated from the point of view of pain. There are currently no husbandry procedures except reduced light intensities that represent viable alternatives to beak trimming, although recent evidence suggests that genetic selection could be used to decrease the incidence of cannibalism in flocks (9).
Beak trimming should not be used indiscriminately, and a judgment must be made as to whether the discomfort involved is necessary in order to prevent or reduce future behaviors that may be deleterious to the bird. When cannibalism occurs in a flock, beak trimming becomes therapeutic. When the decision is made to beak trim, it must be done properly to minimize long-term effects on behavior and production. Guidelines for beak trimming different strains of birds are available from the major breeders.
Toe-trimming is also sometimes used in commercial poultry production. The middle toe of laying hens may be removed to reduce eggshell damage, and the toes of breeder chickens and turkeys may be trimmed to prevent injuries to other birds. Trimming one toe of breeder chickens does not appear to cause chronic pain when performed properly (10).