This article tries to make sense of tail biting in pigs and the effects of tail docking. By giving a number value to the condition of a pigs tail at the time of slaughter, researchers were able to compare data sets and make inferences about tail biting. At slaughter it was found that over 50% of pigs suffered some tail biting despite have their tails docked at birth. The damage done to the tails of pigs who had not been docked, was worse then those who had been. In the EU tail docking is prohibited so a lot of research must be done to find the cause and prevention of tail biting in order to increase the welfare of the pigs.