Avian influenza and other poultry diseases require mass killing of entire flocks. The welfare of millions of birds during emergency depopulation depends critically on the methods used and the speed of response.
Emergency poultry depopulation is a welfare challenge of enormous scale. When avian influenza sweeps through a commercial flock, birds experience disease-related suffering before any culling begins — depopulation speed is therefore a welfare variable, not just an operational one. The methods used for mass killing also carry welfare implications. Whole-house gassing with CO2 or nitrogen is generally considered the most humane approach for large flocks, producing rapid loss of consciousness. Water-based foam suffocation is controversial, with evidence suggesting it may not achieve rapid death consistently. Cervical dislocation is effective for small numbers but impractical at scale. The pressure of outbreak response often compromises method adherence, with welfare cutting corners under time and resource pressure.