Minimising welfare impairment during lairage, handling, and stunning at pig slaughter.
Pre-slaughter welfare represents one of the most significant and addressable welfare challenges in pig production. The lairage period — holding pigs before slaughter — causes acute welfare impairment when poorly managed. Mixing unfamiliar pigs causes fighting that results in injuries and sustained stress. Noise, unfamiliar smells, and the complete change from the familiar farm environment cause fear and distress throughout the process.
Stunning is the critical welfare intervention — effective stunning eliminates consciousness before slaughter, preventing the welfare catastrophe of conscious slaughter. Stunning failures are unacceptably common and represent serious welfare failures. Carbon dioxide stunning — the most widely used method — causes aversive experiences in pigs: gasping, breath-holding, and distress responses before loss of consciousness. High-concentration inert gas stunning (argon, nitrogen) causes rapid unconsciousness without the aversive CO2 effects and represents a significant welfare improvement.
Post-stunning checks are essential — not all pigs are effectively stunned on the first attempt, and recovery of consciousness before slaughter must be detected and prevented through re-stunning.