Tail docking — surgical removal of part of the tail — is performed on dogs, pigs, sheep, and cattle for various reasons, most of which do not hold up to evidence-based scrutiny.
Tail docking causes acute pain at the time of the procedure. For dogs, it is performed purely for aesthetic reasons in show breeds — a cosmetic mutilation prohibited in most of Europe. In pigs, docking addresses a behavioral problem (tail-biting) caused by inadequate housing, not by tails themselves. Addressing root causes — enrichment, space, diet — can achieve equivalent results without the procedure.