Tail docking in dairy cattle was practised to improve udder hygiene and milker comfort, but evidence shows it causes pain and provides no hygiene benefit. It is now banned across most of Europe and increasingly restricted globally.
Tail docking in cattle was one of the clearest examples of a routine painful procedure with no welfare benefit performed primarily for human convenience. The procedure causes acute pain at the time of amputation and potential chronic neuropathic pain from the severed nerve ending. Critically, the evidence base that justified it - improved hygiene and reduced mastitis - was never robust, and controlled studies consistently failed to find hygiene benefits. The flies deterrence function of the tail is substantial: cattle without tails cannot clear flies from their backs, and in summer this results in persistent fly harassment that is itself a welfare harm. The policy outcome - banning across Europe - represents science-based welfare regulation working correctly. The precedent is important for other practices: evidence that a procedure causes pain without demonstrating a compensating welfare benefit justifies prohibition.