The Executive Board, based on the recommendations of the Animal Welfare Committee, amended AVMA position statements on the practices of beak trimming of gallinaceous birds and the housing of layer chickens in cages.
In the modified statement, references to "beak tip amputation" and "debeaking" have been removed, and "beak trimming" inserted. The statement calls for the procedure to be performed "using precision automated equipment, when birds are 10 days of age or younger. Retrimming of beaks is not recommended after birds are 8 weeks old."
Science-based data indicate that poultry breeders can select for behavioral docility in birds and minimize the need to trim beaks. However, under certain management systems and when certain types of birds are used for production, beak trimming is necessary to reduce cannibalism, feather picking, stress, and mortality.
Behavior, physiologic measures of stress, changes in production, and knowledge regarding the neural anatomy and function of the beak have all been used as criteria to determine whether beak trimming compromises bird welfare. Most welfare disadvantages, according to committee, are applicable to individual birds whose beaks have been trimmed and may include difficulty in feeding following beak trimming, short-term pain, chronic pain, and acute stress. Veterinarians must balance the welfare disadvantages of beak trimming with the need to prevent injury and mortality under certain production conditions.
Regarding the housing of layer chickens in cages, the new AVMA policy is:
"Cages should be designed and maintained so as to avoid injury to birds. Construction of cages, feeders, and waterers should take into account scientifically documented advantages for bird comfort and health, and facilitate the safe removal of birds. Cage configuration should be such that manure from birds in upper level cages does not drop directly on birds in lower level cages. All hens should be able to stand comfortably upright in their cages. Feeder space should be sufficient to permit all birds to eat at the same time."
Housing for chicks, pullets, and hens should be constructed and maintained so that birds are protected from predators and environmental extremes. Birds should be managed so that transmission of disease, parasitic infection, and vermin infestation are minimized. Cage design must facilitate daily care and inspection of birds.
Although results of numerous studies indicate that insufficient cage space significantly reduces egg production and increases mortality, specific recommendations for cage size have not been included in the position statement because cage space will vary, depending on the type of cage and the birds housed.