Highly pathogenic avian influenza (HPAI) outbreaks require mass culling of poultry flocks, causing extreme welfare harm and raising questions about prevention through housing and biosecurity.
Mass depopulation of HPAI-infected flocks involves killing large numbers of birds rapidly, often using methods that cause suffering at scale. Carbon dioxide produces distress before unconsciousness in densely packed birds. Heat treatment and water-based foam are alternatives with varying welfare profiles. Culled birds had not yet developed disease but are killed as a precautionary measure. Prevention through vaccination, biosecurity, and housing management can reduce the need for culling but is expensive and logistically challenging.