Welfare implications of horse tail modifications

Literature review

May 12, 2012

This peer-reviewed summary has been prepared by the American Veterinary Medical Association Animal Welfare Division. While principally a review of the scientific literature, it may also include information gleaned from proprietary data, legislative and regulatory review, market conditions, and scholarly ethical assessments. It is provided as information and its contents should not be construed as official AVMA policy. Mention of trade names, products, commercial practices or organizations does not imply endorsement by the American Veterinary Medical Association.


Docking—Amputation of the distal part of the boney part of the tail.3 A horse’s tail contains 15 to 21 vertebrae, docking typically leaves a tail approximately 15 cm (6 inches) long.1,2 In most cases, tails of foals are docked using a constricting band. In some cases ‘docking’ is used interchangeably with trimming to refer only to shortening of tail hair.
Nicking—Cutting tail tendons to cause an elevated carriage of the tail3 (pricking).
Blocking—Numbing the tail to cause it to hang limply, usually achieved by injecting alcohol into the tail close to major nerves3 (deadening, nerving).


Docking traditionally has been performed to prevent the tail of the horse from interfering with harness and carriage equipment. Specifically, if a rein passes under the horse’s tail the horse may clamp its tail down and cause the driver to lose control of the horse. Docking may also be used to improve cleanliness of the tail and to make harnessing easier. However these justifications are not universally accepted.2
Docked tails became cosmetically fashionable in some breeds where the procedure is performed, according to custom, for competitions or shows. Docking is rarely performed on non-draft breeds but surveys have found that approximately half1 of draft horses’ tails are docked,4 usually by use of a constricting band.
The Animal Welfare Council of Belgium conducted a review and concluded that tail docking was not necessary for draft horses; consequently it supported a national ban.5 Docking has also been described as cosmetic in the veterinary literature.6
Welfare concerns appear to relate less to the pain that might be caused by the procedure7,8, and more to the surgery being unnecessary and reducing the tail to the extent that it cannot be used to fend off flies and biting insects.9,10 The intact tail is also useful to the horse for displays of mental11 and physiological states (e.g., estrus).10


Nicking is sometimes performed on breeds (e.g., saddlebreds) for which show standards reward the tail being carried erect rather than lying flat. The practice may have developed for the same reason as docking, to keep the tail clear of harnesses. However it is now performed only for showing/cosmetic reasons.12 Nicking involves an incision and, in rare cases, serious or fatal complications have been reported due to infections resulting in peritonitis.13 As nicked tails will naturally settle back into a relaxed position, these horses often wear ‘tail sets’ to hold the tail erect. While wearing this equipment horses need to be stabled individually.
Veterinary objections to this procedure can be found in publications as early as 185514 (“It is a surgical operation, but no respectable veterinarian would recommend it”).


Blocking is performed to prevent agitated tail movements during performances, which leads to the deduction of points. It is performed on horses in Western riding disciplines and is uncommon outside the United States.3

Law and policy

In the United States ten states prohibit docking of horses’ tails entirely or unless rendered necessary (i.e., medically, to benefit the animal, or in case of emergency). New Hampshire permits the procedure only with permission from the state veterinarian.
Docking is banned in Austria, Belgium, Denmark, Finland, Germany, Ireland, Portugal, Norway, Sweden and the United Kingdom. It is permitted in Luxemburg and Spain (excluding Catalonia and Andalucía).
The American Association of Equine Practitioners policy states, in part, that: “The American Association of Equine Practitioners is opposed to the alteration of the tail of the horse for cosmetic or competitive purposes.”


It has been widely suggested that veterinarians should avoid performing surgical procedures that are cosmetic, not medically necessary, or not for the net benefit of the animal.15 There is a lack of reliable data indicating when (or whether) tail docking is beneficial to the horse other than when performed on an animal with a defect or injury

1 Nebergall SA. How to perform surgical tail docking in draft horses. Proceedings of the American Association of Equine Practitioners 1999, 45, 113–114.
2 Hayes MH. Veterinary notes for horse owners 1903 London: Hurst and Blackett.
3 Tozzini S. Hair today, gone tomorrow: equine cosmetic crimes and other tails of woe. Anim. Law 2003;9:159–181.
4 Christie JL, Hewson CJ, Riley CB, McNiven MA, Dohoo IR, Bate LA. Demographics, management, and welfare of nonracing horses in Prince Edward Island. Canadian Vet J 2004;45: 1004–1011.
5 Lefebvre D, Lips D, Odberg FO, Giffroy JM. Tail docking in horses: a review of the issues. Animal 2007;1:1167-1178.
6 Neumann S. Cosmetic surgery: customer service or professional misconduct. Canadian Vet J 2008;49: 501–504.
7 Stafford KJ, Mellor DJ. Painful husbandry procedures in livestock and poultry. In Grandin T [ed] Improving Animal Welfare: A Practical Approach 2010. :CABI: Oxfordshire.
8 Anonymous. Say docking doesn’t hurt. New York Times 1904; March 24 [no page number available].
9 Keiper RR, Berger J. Refuge-seeking and pest avoidance by feral horses in desert and island environments. Appl Anim Eth 1982:9;111–120.
10 Waring GH (1983) Horse Behavior. William Andrew: New York.
11 Hendriksen P, Elmgreen K, Ladewig J. Trailer-loading of horses: Is there a difference between positive and negative reinforcement concerning effectiveness and stress-related signs? J Vet Behav Clin Appl Res 2011; 6:261-266.
12 Wilcox, C. The American Saddlebred Horse 1996. Bloomington: Capstone Press.
13 Moll DH, Schumacher J. Septic peritonitis associated with caudal myotomy in a Tennessee walking horse. J. Am. Vet. Med. Assoc 1992;201:458-459 .
14 Stewart J. The stable book; being a treatise on the management of horses, in relation to stabling, grooming, feeding, watering and working. Construction of stables, ventilation, stable appendages, management of the feet. Management of diseased and defective horses. With notes and additions adapting it to American food and climate 1855, New York, Orange Judd.