Beak Trimming

Within the poultry industry bird aggression and cannibalism result in decreased animal welfare, as well as cost producers a significant amount of profit loss. In an attempt to reduce these behaviors a management practice referred to as beak trimming, or “debeaking”, was developed. In this method up to one half of the upper, or both, mandible(s) are removed mechanically- usually by use of a hot blade (United) or through electric or infrared removal, leaving the beak blunt. Although pain does result from the removal of innervated tissues causing some behavior changes for a period of time (Gentle), the pain suffered from continual attack combined with the continued losses to the producer, by far make beak trimming an advantageous solution for large scale commercial production. Until alternate solutions can feasibly reduce the amount of bird  damage and loss in large flocks with long term maintenance, then beak trimming is a viable and necessary production method. Furthermore if the trimming is performed at a very young age and in a manner that results in no more than one-third of the beak removed-with both mandibles trimmed, than the birds have an easier time feeding and their behavior does not remain as significantly altered for an extended period of time (Gentle).

 Small flock owners, and animal rights and welfare groups provide the most prominent voice against beak trimming, finding the practice distasteful due to the pain and behavioral changes that occur in the post-operative birds (Gentle). These groups often argue emotionally for the end of beak trimming, a method often critiqued hand-in hand with caging and the overcrowding of birds, associated with dense populations used in modern commercial practices. Rather than “mutilating” (United) birds, these groups support ensuring that the birds have ample room, dimmed lights, a balanced high fiber diet and the prompt removal of any birds that are alternately colored, injured, or slow-feathering from the flock (Clauer). These recommendations, while viable methods for diffusing flock aggression, are not practical for large scale flocks which cannot be continuously monitored, or for conditions in which damage to birds may naturally occur such as during mating in breeding flocks.

It cannot be denied that beak trimming results in pain associated with amputation. Numerous studies have shown increased neural damage (Gentle), and observed pain through behavioral changes (Cunningham); However, the intensity of behavioral changes varied with the proportion of the beak removed. It should also be noted that depending on the behavior, observational changes subsided after a five week period. Behaviors such as feeding and drinking showed an initial decrease in studies, but returned to post-operative levels approximately three weeks following the removal of the tip of the beaks (Duncan). This reduction in pecking, and thus weight, is usually attributed to the occurrence of pain in the amputated area, however Gentle et al suggested that this decrease is part of an adjustment period for the bird which must now learn to use its altered morphology and compensate with a shortened beak. It was also shown that the birds which only had one-third of their beaks trimmed were much less affected and showed a quicker return to normal behavior.

Some behaviors, such as increased standing and sleeping and decreased preening also occurred. These behaviors, however remained altered at the end of a five week period of observation (Duncan). Although these behaviors are considered a variant from non-trimmed birds and are thought of as a decrease in the welfare of individual birds, decreased activity may be considered an increase in welfare of the entire flock. If individual birds are content spending more time asleep rather than actively seeking out interactions among their flock mates, then the rate of cannibalism and  aggression amongst birds will decrease. As Cunningham noted, it is important in commercial production operations for the producer to balance the reductions and gains in welfare for the entire flock to maximize the welfare of the entire group.

In the same sense, it is important in commercial production practices to evaluate the practicality of alternative management techniques. While providing ample space with access to the outdoors and a close daily inspection of all birds may be feasible in a small flock, at a commercial level it simply isn’t practical. Some techniques detailed in Clauer’s guide to the prevention of cannibalism, such as maintaining low-intensity lighting and providing adequate diets can be met by producers. However, if these changes cannot ensure a reduction of flock mortalities than beak trimming will continue to be the most accepted practice by commercial producers (Cunningham). By combining various techniques, such as reducing the lights and the amount of beak trimmed, a more acceptable level of individual welfare may be provided while remaining practical for producers.

Flock welfare is a real concern for producers and activist alike. At this time the most practical method of controlling cannibalism and aggression among a flock is the removal of a portion of the beak. In removing only one-third of the beak individual welfare can be improved and when combined with alternative methods of behavior modification- such as dimming the lighting available to the birds, aggressive behavior may be limited without significantly modifying other aspects of behavior or welfare. Although it has been proven that beak trimming does cause pain it is the only method that can ensure a decrease in mortality in commercial flocks at this time. New research is continuously being developed to find alternative methods for aggression control. One such example is a method of gait analysis via computer markers that may be able to determine aggressive tendencies among a flock and identify individuals more likely to cause cannibalism related problems (Laursen). Although this technology remains far from being available, it may one day provide more options for commercial producers or be able to further research to understand flock behavior.

References

Clauer, P. J. 2009 Cannibalism: Prevention and Treatment. Virginia Cooperative Extension http://pubs.ext.vt.edu/2902/2902-1095/2902-1095.html

Cunningham, D. L. 1992 Beak Trimming Effects on Performance, Behavior and Welfare of Chickens: A Review J APPL POULT RES 1992 1: 129-134

Duncan, I. J. H. , Slee, Gillian S. , Seawright, Elaine and Breward, J.1989 'Behavioural consequences of partial beak amputation (beak trimming) in poultry', British Poultry Science, 30: 3, 479 — 488

Gentle, M.J. Hughes, B.O., Hubrecht, R.C., 1982. The effect of beak trimming on food-intake, feeding-behaviour and body-weight in adult hens. Appl. Anim. Ethol. 8, 147–159.

Laursen, L. 2010 Computer System Counters Hen Horrors. IEEE Spectrum News. http://spectrum.ieee.org/biomedical/diagnostics/computer-system-counters-hen-horrors

United Poultry Concerns, Inc. Deabeaking. http://www.upc-online.org/merchandise/debeak_factsheet.html