Docking is a term for the intentional removal of part of an animal's tail

Tail

The tail is the section at the rear end of an animal's body; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, reptiles, and birds...

 or ear

Ear

The ear is the organ that detects sound. It not only receives sound, but also aids in balance and body position. The ear is part of the auditory system....

s. The term cropping is also used, though more commonly in reference to the cropping

Cropping (animal)

Cropping is the removal of part or all of the pinnae or auricles, the external visible flap of the ear, of an animal. Most commonly performed on dogs, it is an ancient practice that was once done for perceived health, practical or cosmetic reasons...

 of ears, while docking more commonly—but not exclusively—refers to the tail. The term tailing is also commonly used. The term arises because the living flesh of the tail, from which the animal's tail hairs grow, commonly is known as the dock.

History

Originally, most docking was done for practical purposes. For example, a large horse

Horse

The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...

 used for hauling large loads might have its tail docked to prevent it from becoming entangled in tow ropes or harness; without docking, it could be dangerous to the horse, painful if the tail were tangled, and inconvenient to the owner to tie up the horse's tail for every use.

Agricultural practice

Tail docking may be performed on livestock

Livestock

Livestock refers to one or more domesticated animals raised in an agricultural setting to produce commodities such as food, fiber and labor. The term "livestock" as used in this article does not include poultry or farmed fish; however the inclusion of these, especially poultry, within the meaning...

 for a variety of reasons:

• In the case of domestic pig
  Domestic pig
  The domestic pig is a domesticated animal that traces its ancestry to the wild boar, and is considered a subspecies of the wild boar or a distinct species in its own right. It is likely the wild boar was domesticated as early as 13,000 BC in the Tigris River basin...
  
  s, where commercially raised animals are kept in close quarters
  Intensive pig farming
  Intensive piggeries are a type of factory farm ' specialized in the raising of domestic pigs up to slaughter weight...
  
  , tail docking is performed to prevent injury or to prevent animals from chewing or biting each others' tails.

• Many breeds of sheep have their tails docked to reduce fly strike
  Myiasis
  Myiasis is a general term for infection by parasitic fly larvae feeding on the host's necrotic or living tissue. Colloquialisms for myiasis include flystrike, blowfly strike, and fly-blown. In Greek, "myia" means fly....
  
  . Also used for this purpose is mulesing
  Mulesing
  Mulesing is a skilled surgical task that involves the removal of strips of wool-bearing skin from around the breech of a sheep to prevent flystrike in regions where it is common....
  
  .

While tail docking is an effective preventive method in some cases, if it is not carried out correctly it may result in other problems such as rectal prolapse

Rectal prolapse

Rectal prolapse normally describes a medical condition wherein the walls of the rectum protrude through the anus and hence become visible outside the body.-Types:There are three chief conditions which come under the title rectal prolapse:...

 or ill thrift

Failure to thrive

Failure to thrive is a medical term which is used in both pediatric and adult human medicine, as well as veterinary medicine ....

.

Depending on the animal and the culture, docking may be done by cutting (knife or other blade), searing (gas or electrically heated searing iron), or constriction methods, i.e. rubber ring elastration

Elastration

Elastration is a bloodless method of male castration and docking commonly used for livestock. Elastration is simply banding the body part until it drops off...

.

As with docking of dogs, it has been identified that this practice contributes to masking underlying shortcoming of a breed, which - if docking were not the general practice - would be countered through selective breeding of animals where the tail does not lead to medical problems.

Dogs

As with other domesticated animals there is a long history of docking the tails of dogs. It is understood to date at least to the Roman Empire. The most popular reason for docking dog breeds is to prevent injury to working dogs. For instance, it has been stated that a vermin's bite to the working dog's flop ears can lead to a systemic infection, a serious medical problem that wouldn't occur were there no flop ears to be bitten. In hunting dogs, the tail is docked to prevent it from getting cut up as the dog wags its tail in the brush. This is contested by a wide range of groups and is often considered a form of animal cruelty

Cruelty to animals

Cruelty to animals, also called animal abuse or animal neglect, is the infliction of suffering or harm upon non-human animals, for purposes other than self-defense. More narrowly, it can be harm for specific gain, such as killing animals for food or for their fur, although opinions differ with...

 and torture

Torture

Torture is the act of inflicting severe pain as a means of punishment, revenge, forcing information or a confession, or simply as an act of cruelty. Throughout history, torture has often been used as a method of political re-education, interrogation, punishment, and coercion...

. This has led to the practice being outlawed and made illegal throughout many countries, in some of which dogs are no longer bred for work, or used as working animal

Working animal

A working animal is an animal, usually domesticated, that is kept by humans and trained to perform tasks. They may be close members of the family, such as guide or service dogs, or they may be animals trained strictly to perform a job, such as logging elephants. They may also be used for milk, a...

s.

For example, in United Kingdom tail docking was originally undertaken largely by dog breeders. However, in 1991, the UK government amended the Veterinary Surgeons Act (1966), prohibiting the docking of dogs' tails by lay persons from 1 July 1993. Only veterinary surgeons were, by law, allowed to dock. However, following the passage of the law, the Council of the Royal College of Veterinary Surgeons in November 1992, ruled docking to be unethical, "unless for therapeutic or acceptable prophylactic reasons". The requirement in which the Royal College considers prophylactic docking to be acceptable are so strict as to make the routine docking of puppies by veterinary surgeons extremely difficult. Vets who continue to dock risk disciplinary action, and can be removed from the professional register. Those found guilty of unlawful docking would face a fine of up to £20,000, up to 51 weeks imprisonment or both. They can only dock the tail of "working" dogs (in some specific cases) - e.g. hunting dogs that work in areas thick in brambles and heavy vegetation where the dog's tail can get caught and cause injury to the dog. Docking was banned in England and Wales

England and Wales

England and Wales is a jurisdiction within the United Kingdom. It consists of England and Wales, two of the four countries of the United Kingdom...

 by the Animal Welfare Act 2006

Animal Welfare Act 2006

The Animal Welfare Act 2006 is an Act of the Parliament of the United Kingdom.It is the first overhaul of pet law since the Protection of Animals Act 1911, which it largely replaced. It also superseded and consolidated more than 20 other pieces of legislation, such as the Protection of Animals Act...

 and in Scotland by the Animal Health and Welfare (Scotland) Act 2006

Animal Health and Welfare (Scotland) Act 2006

The Animal Health and Welfare Act 2006 is an Act of the Scottish Parliament. It received Royal Assent on 11 July 2006.The act consolidated, repealed and replaced many other pieces of legislation, such as the Protection of Animals Act 1934 and the Abandonment of Animals Act 1960.The act bans tail...

.

In 1987 the European Convention for the Protection of Pet Animals

European Convention for the Protection of Pet Animals

The European Convention for the Protection of Pet Animals is a treaty of the Council of Europe to promote the welfare of pet animals and ensure minimum standards for their treatment and protection. The treaty was signed in 1987 and became effective on May 1, 1992, after at least four countries had...

, established by Council of Europe, prohibited docking for non-medical reasons, though signatory countries are free to opt out of this provision, and almost half of them have done so. Norway completely banned the practice in 1987. Other countries where docking is banned: Australia, Austria, Belgium, Brazil, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Israel, Italy, Latvia, Lithuania, Luxembourg, the Netherlands, Norway, Slovakia, Sweden, Switzerland, the Virgin Islands.

Horses

In modern use, the term usually does not refer to tail amputation

Amputation

Amputation is the removal of a body extremity by trauma, prolonged constriction, or surgery. As a surgical measure, it is used to control pain or a disease process in the affected limb, such as malignancy or gangrene. In some cases, it is carried out on individuals as a preventative surgery for...

 as it does with some dog

Dog

The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...

 breeds. However, historically, docking was performed on some horses, often as foal

Foal

A foal is an equine, particularly a horse, that is one year old or younger. More specific terms are colt for a male foal and filly for a female foal, but these terms are used until the horse is age three or four. When the foal is nursing from its dam , it may also be called a suckling...

s. The practice has been banned in some nations, but is still seen on some show and working draft horses in some places, and is practiced at some PMU

Premarin

Premarin is the commercial name for a compound cream of vaginally administered estrogens, consisting primarily of conjugated estrogens. Isolated from mares' urine , it is manufactured by Wyeth Pharmaceuticals and has been marketed since 1942...

 operations.

In modern times, the term "docked" or "docking" in reference to the tail of a horse generally refers to the practice of cutting the hair of the tail skirt very short, just past the end of the natural dock

Rump (animal)

The rump or croup, in the external morphology of an animal, is the portion of the posterior dorsum that is posterior to the loins and anterior to the tail. Anatomically, the rump corresponds to the sacrum....

 of the tail. In particular, the tail is often cut short to keep it from being tangled in a harness

Horse harness

A horse harness is a type of horse tack that allows a horse or other equine to pull various horse-drawn vehicles such as a carriage, wagon or sleigh. Harnesses may also be used to hitch animals to other loads such as a plow or canal boat....

.

Cattle

Cattle on large Australian cattle station

Cattle station

Cattle station is an Australian term for a large farm , whose main activity is the rearing of cattle. In Australia, the owner of a cattle station is called a grazier...

s often have the tail brush (not the dock) cut shorter (banged) before their release; this "bang-tail muster" indicates those having been counted, treated, their current pregnancy status determined, etc.