Surgical castration of male piglets without anaesthetic is common in many countries to prevent boar taint in pork, but causes acute pain and remains a significant welfare controversy.
Piglets castrated without anaesthetic show clear behavioural signs of acute pain: vocalisation, escape attempts and stress postures. Post-operative pain may last several days. Alternatives including immunocastration (Improvac vaccine), entire male production with taint detection and genetic selection avoid the procedure entirely. The welfare case against surgical castration without pain relief is overwhelming.