Welfare of Pigs During Gas Stunning for Slaughter

High CO2 stunning used in many pig slaughter facilities causes distress before unconsciousness, and welfare improvements remain a priority.

Key Facts

High CO2 gas stunning is used in most large pig slaughter facilities in Europe
Pigs take 15-30 seconds to lose consciousness during CO2 stunning
During this period pigs show clear signs of distress including attempts to escape
Low oxygen mixtures cause loss of consciousness more rapidly with less distress
Electrical stunning to the head can render pigs unconscious more quickly

Welfare Considerations

Pigs in CO2 gas chambers experience acute distress during the period of consciousness before the gas takes effect. The aversive respiratory sensation of CO2 causes hyperventilation, vocalizations, and frantic escape attempts. This period of suffering, though brief, occurs in every pig stunned by this method and represents hundreds of millions of individual welfare incidents annually. Alternative stunning methods including low-O2 mixtures and head-only electrical stunning can reduce or eliminate this pre-stun distress.

What You Can Do

Advocate for adoption of less aversive stunning methods in pig slaughter
Support certification programs that require welfare-positive stunning methods
Choose pork from farms that slaughter using head-only electrical or low-O2 systems
Donate to organizations researching and promoting humane slaughter methods