THE ISSUE
Some dog breed standards and traditions specify or allow the amputation of part of a dog's tail. Cosmetic surgery is generally not allowed to be performed on show dogs, but tail docking is an exception for breeds for which this is customary. In the United States the tails of dogs belonging to these breeds are often docked, in both working and pet situations.

DOCKING
Puppies' tails are docked during the first five days of life, either surgically or with a constricting band.

WELFARE CONCERNS—RISKS
The welfare issues surrounding tail docking have been extensively reviewed,^1,2,3,4 but the practice has been the subject of very few controlled studies comparing otherwise equivalent dogs whose tails are docked or undocked.

Pain—Surgical amputation of the dog's tail produces behaviors indicative of short-term pain.⁵

Complications—As with any surgical procedure, there is potential for complications such as excessive bleeding, infection, and necrosis. Neuromas, which have been associated with chronic pain, may develop, but their incidence and persistence is not known.

Chronic Health Issues—It has been suggested that dogs whose tails are docked may have underdeveloped pelvic musculature; the evidence, however, is not conclusive. Dogs of breeds that are docked have a higher incidence of incontinence; however, this may be due to traits other than docked tails.⁶ Dogs with docked tails within some breeds may have less well developed levator ani and coccygeus muscles.⁷

REASONS GIVEN FOR THE PRACTICE
Human Benefits—The primary reason for tail docking appears to be maintenance of a distinctive appearance for a particular breed, and to take part in an ongoing tradition. The value some communities place on docking may indirectly affect animal welfare if it motivates less skilled persons to carry out a procedure when a veterinarian refuses to perform that procedure, or if a dog whose tail is not docked is less able to be placed in a suitable home.

Animal Benefits—It has been suggested that docking protects the animal from later tail damage, in cases where the breed is more vulnerable or more likely to experience tail injury during its activities (e.g., breeds that hunt in thick cover and have vigorous tail action). Tail injuries generally have a low rate of occurrence⁸ and many working breeds' tails go undocked. However, the German Shorthaired Pointer Breed Council collected breeder reports showing a high incidence of tail injury after the 1990 ban on docking in Sweden. It is possible that some breeds and uses are particularly vulnerable to tail trauma, but peer-reviewed data is lacking.

It has also been suggested that accidental tail trauma to the adult dog causes more suffering than amputation early in life. Although it is not currently accepted that puppies experience less pain than adult dogs, especially as analgesia is rarely provided for them, they can be docked quickly under controlled circumstances while fully restrained; this could minimize the chance for protracted suffering. However, it has not been demonstrated that breeds whose tails are traditionally docked have a significant risk of tail trauma that would justify the docking of their tails.

TAIL DOCKING IN OTHER SPECIES
Tail docking is has performed for other species when not doing so results in these animals having a demonstrably high risk of suffering (e.g., fly strike in sheep, tail-biting in pigs). However, even for these species the procedure is gradually being considered to be less and less acceptable. Research into alternative solutions for these species is ongoing and not all facilities dock preventively. Docking became less favored for dairy cows and horses when justifications for the practice were deemed to be insufficient.

LEGISLATION AND ACCEPTABILITY
Across a range of countries routine docking is considered unacceptable by most veterinarians (83 to 92%^9,10) and the general public (68 to 88%¹¹). In contrast, many breeders with a prior commitment to this practice^12, remain in favor of tail docking (84 to 87%^13,).

SUMMARY
Empirical studies of docking methods and the long-term consequences of docking that include a suitable population of control animals would be helpful in developing a consensus regarding the welfare implications of this procedure. However as veterinary and general public acceptance of the procedure appears to be low, and arguably declining, there is little impetus for further research. At this time routine tail docking has not been shown to produce demonstrable benefits for the typical dog. When it is performed routinely, rather than in response to a medical need (such as tail trauma), it is considered to be cosmetic surgery.

REFERENCES
1. Morton D. Docking of dogs: practical and ethical aspects. Vet Rec 1992;131:301-306.
2. Bennett P, Perini E. Tail docking in dogs: a review of the issues. Aust Vet J 2003;81:208-218.
3. Wansborough R. Cosmetic tail docking of dogs. Aust Vet J 1996;74:59-63.
4. Department for Environment Food and Rural Affairs (DEFRA) Web site A review of the scientific aspects and veterinary opinions relating to tail docking in dogs. Available at: http://www.defra.gov.uk/animalh/welfare/domestic/awbillconsulttaildocking.pdf. Accessed July 11, 2007.
5. Noonan G, Rand J, Blackshaw J, et al. Behavioural observations of puppies undergoing tail docking. Appl Anim Behav Sci 1996;4: 335-342.
6. Thrusfield P, Holt M. Association in bitches between breed, size, neutering and docking, and acquired urinary incontinence due to incompetence of the urethral sphincter mechanism. Vet Rec 1993;133:177-180.
7. Canfield R. Anatomical aspects of perineal hernia in the dog. 1986 PhD Doctoral thesis: University of Sydney.
8. Darke PGG, Thrusfield MV, Aitken CGG. Association between tail injuries and docking in dogs. Veterinary Record 1985;11:409
9. Noonan GJ, Rand JS, Blackshaw JK, et al. Tail docking in dogs: a sample of attitudes of veterinarians and dog breeders in Queensland. Aust Vet J 1996;73:86-88.
10. Council of Docked Breeds Web site. BSAVA Docking Questionnaire Results Available at: http://www.cdb.org/bsava.htm 2007 -- see also British Veterinary Association (BVA) Web site. Every Dog Should Have a Tail to Tell Available at: http://www.bva.co.uk/policy/issues/docking.asp. Accessed July 11, 2007.
11. Submission to Government Administration Committee presented by Royal New Zealand Society for the Prevention of Cruelty to Animals Incorporated in the matter of animal welfare (restriction on docking of dogs' tails) bill. Feb 25, 2005.
12. Bennett PC, Perini E. Tail docking in dogs: can attitude change be achieved? Aust Vet J 2003;81:277-82.
13. Council of Docked Breeds Web site. UK Tail Docking Survey Available at: http://www.dockingsurvey.org/ Accessed July 11, 2007.

This information has been prepared as a service by the American Veterinary Medical Association's Animal Welfare Division. Redistribution is acceptable, but the document's original content and format must be maintained, and its source must be prominently identified.