The hours before slaughter in lairage pens are a critical welfare period, with mixing, fasting, noise, and unfamiliar environments causing significant stress.
Lairage represents a concentration of multiple simultaneous welfare stressors: social disruption, unfamiliar environment, novel smells, noise, food deprivation, and loss of predictability. Cortisol levels are measurably elevated from the point of loading and remain high throughout transport and lairage. Fighting in mixed groups causes visible injuries. Pigs are particularly sensitive to lairage conditions due to their social complexity. Low-stress handling techniques and effective design reduce but cannot eliminate lairage welfare harms.