The slaughter process is the final welfare event in a pig's life, and stunning method, handling in lairage, and restraint design all significantly affect the welfare of millions of pigs annually.
The welfare of pigs at slaughter has received increasing scientific attention. CO2 stunning causes aversion — pigs avoid CO2 and show distress signs during exposure before losing consciousness. This has led to research into inert gas alternatives. Electrical stunning is faster to consciousness loss but has higher risk of incomplete stunning. Pre-slaughter handling — the period in lairage awaiting slaughter — is a significant welfare event, with mixing of unfamiliar pigs causing aggression, and excessive waiting time causing stress. Welfare assessment at abattoir, including monitoring of stun effectiveness and pre-slaughter handling quality, provides the data needed to drive improvement. The HSA Approved Certificate qualification ensures slaughter operators have minimum competency in welfare-conscious slaughter practice.