Save the pig tail - because they´re worth it

A recent scientific review describes how tail docking causes some pain to 100% of the pigs, and reduces the risk of tail biting (approximately 2-fold, based on available abattoir data). Even though the risk for tail biting might be higher if tails are not docked, and the pain caused by biting more intense than the pain caused by docking, the non-bitten pigs are fully spared the pain due to tail docking in a 0% docking scenario. Pigs that are both docked and bitten suffer the most pain. In addition to this, undocked pigs will likely be kept on better management level.

Tail biting is a common problem in modern pig production and has a negative impact on both animal welfare and economic result of the farm. Tail biting risk is increased by management and housing practices that fail to meet the basic needs of pigs. Tail docking is commonly used to reduce the risk of tail biting, but tail docking in itself is a welfare problem, as it causes pain to the pigs, and facilitates suboptimal production methods from a welfare point-of-view. When evaluating the cost and benefit of tail docking, it is important to consider negative impacts of both tail docking and tail biting.  Data suggests that tail biting can be managed to an acceptable level even without tail docking, by correcting the production system to better meet the basic needs of the pigs. 

Valros and Heinonen Porcine Health Management 2015, 1:2