Mulesing - removal of skin around the breech of Merino sheep to prevent flystrike - is one of the most controversial farm animal welfare procedures. Alternatives are available but transition is complex.
Mulesing causes significant acute pain - the procedure involves removing substantial areas of skin from unanesthetized lambs using shears. Pain scores remain elevated for multiple days following the procedure. The welfare case against mulesing without pain relief is strong, yet implementation of mandatory pain relief has been slow and inconsistent across Australian states. The underlying cause of mulesing necessity - the highly wrinkled Merino genetics bred for extreme wool production - creates a self-perpetuating cycle where increased wrinkle increases flystrike risk requiring mulesing. Selection for reduced wrinkle and increased flystrike resistance can produce wool of comparable quality without the same vulnerability, but genetic change is slow. The New Zealand transition demonstrates that alternatives are commercially viable.