Poultry Welfare During Depopulation Events

Mass depopulation of poultry during disease outbreaks, particularly avian influenza, raises acute welfare concerns about killing methods and the suffering of billions of birds during emergency culls.

Key Facts

Avian influenza outbreaks have resulted in culling of over 150 million birds globally in each of the 2021-22 and 2022-23 seasons
UK culling methods include whole house gassing with CO2, ventilation shutdown plus heat (VSD+), and injectable barbiturate
VSD+ is considered inhumane by many welfare organisations - it involves gradually heating buildings to cause fatal hyperthermia
CO2 gassing at high concentrations causes respiratory distress before loss of consciousness
More humane culling methods including firefighting foam and nitrogen hypoxia are available but less widely deployed
Disease culling is legally required to prevent spread but the method choice has significant welfare implications
Pre-cull stunning followed by cervical dislocation is more welfare-friendly for smaller flocks but impractical at large scale
International standards (OIE) provide guidance on acceptable and unacceptable culling methods

Welfare Considerations

Emergency depopulation during disease outbreaks creates one of the most acute welfare crises in farm animal production. The sheer scale - millions or tens of millions of birds in a single outbreak region - and the urgency of disease control create pressure to use the most logistically convenient rather than the most welfare-friendly methods. VSD+ is widely condemned by welfare organisations because birds experience progressive heat stress, respiratory distress, and neurological signs over an extended period before death. CO2 at high concentrations also causes distress. More humane methods exist and should be the default - the welfare obligation does not diminish because killing is legally required. Better emergency planning and pre-positioned welfare-friendly equipment would reduce the use of inhumane emergency methods.

What You Can Do

Advocate for welfare-friendly culling methods (nitrogen hypoxia, firefighting foam, low-concentration CO2 with gradual increase) to become the regulatory default
Support organisations including the Humane Slaughter Association in their work on emergency killing methods
Engage with Defra consultation processes on avian influenza preparedness to include welfare method standards
Support research into more humane emergency killing methods for large-scale poultry depopulation
Advocate against the use of VSD+ as an emergency culling method in UK policy
Engage with poultry industry and government to pre-position humane killing equipment at high-risk facilities