An animal welfare campaign group is urging an end to the practice of routinely chopping off piglets' tails.

Compassion in World Farming (CIWF) wants the UK Government to ban the docking, which it calls "painful and unnecessary mutilation".

The docking involves slicing off part of the tail with pliers, or with a hot docking iron. Farmers say it causes temporary discomfort.

But CIWF says a report by its research wing, CIWF Trust, which is based on the scientific literature, shows that the docking is painful not only at the time but sometimes for life.

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The docking is done to prevent the animals biting one another's tails, which can then become infected. CIWF says it is the conditions in which the pigs are kept that causes the problem.

Peter Stevenson of CIWF said that 12 million UK piglets a year were docked "for no good reason. Tail-biting is a sure sign that something is wrong with the farming system".

"Most pigs today are factory-farmed - they are kept indoors throughout their lives in barren, overcrowded pens.

"Often they are given no straw, being kept instead on bare concrete or slatted or perforated floors. In these conditions they are unable to perform their natural behaviours of rooting, foraging and exploring.

"Bored and frustrated, they turn to the only other 'thing' in their pens: the tails of other pigs."

The report says better living conditions would solve the problem.

"Scientific research shows that most tail-biting can be prevented if pigs are given straw to enable them to root and chew, sufficient space to prevent overcrowding, and an adequate supply of good food and water."

An ineffective ban

Although routine tail-docking has been banned since 1994, farmers may dock animals where there is evidence that tail-biting has happened because of a failure to dock them.

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CIWF says the exception "is so broad that the ban is widely ignored, with 75% to 80% of piglets still being tail-docked".

In 1997 the European Union's scientific veterinary committee said: "The problems of injury following tail-biting should be solved by improved management, not by tail-docking."

The Labour Party promised before the last general election to ensure that docking was ended, except for veterinary purposes.

The National Farmers' Union said there was evidence that tail-biting could still occur when pigs had straw to lie on.

It said biting could cause serious problems, and could start for no apparent reason, and on balance docking, on a vet's advice, was the best treatment.