Mulesing is a surgical procedure removing skin from around the breech of Merino sheep to prevent flystrike, causing significant pain and distress.
Mulesing causes significant acute pain — sheep show pain behaviours including vocalisations, abnormal postures, and reduced activity for days after the procedure. The wound takes weeks to heal, during which it may itself attract flies. While mulesing addresses a genuine welfare problem (flystrike causes severe suffering), the procedure itself imposes substantial pain that is widely considered disproportionate when alternatives exist. Many major wool purchasers now require non-mulesed certification from their suppliers.