Farm Animals

Welfare of Livestock During Slaughter: Stunning Methods

Pre-slaughter stunning is the primary welfare intervention at slaughter, but methods vary in reliability and effectiveness across species and operations.

Key Facts

Captive bolt stunning is the most common method for cattle and sheep
Electrical stunning is standard for pigs and poultry in most regulated systems
Water bath electrical stunning of poultry raises significant welfare concerns during shackling
CO2 stunning of pigs causes distress during the aversion phase before unconsciousness
Head-only electrical stunning is reversible — animals can regain consciousness if slaughter is delayed

Welfare Considerations

Stunning effectiveness is highly variable in practice even when the correct method is specified. Equipment calibration, maintenance, operator training, and line speed all affect whether animals are rendered genuinely insensible before slaughter. Auditing of stunning effectiveness is typically limited to periodic inspection rather than continuous monitoring. CCTV with independent access has been shown to improve stunning compliance in facilities that have adopted it.

What You Can Do

Advocate for mandatory CCTV with independent access in all slaughter facilities
Support line speed reduction requirements that allow adequate time for stunning verification
Pressure meat retailers to require stunning compliance auditing in their supplier specifications
Follow updates on CO2 stunning welfare debates and support higher concentration requirements for pigs