Good biosecurity prevents disease outbreaks that cause severe welfare harm to farm animals, making it one of the most important welfare-positive management practices.
Disease biosecurity is welfare-positive at two scales: it prevents individual animals from experiencing disease-related suffering, and it prevents the mass culling events that kill millions of animals when notifiable diseases spread unchecked. Foot and mouth outbreaks that trigger mass culls cause acute welfare harm through the killing itself, and the stress of herd depopulation events for animals awaiting slaughter. Avian influenza outbreaks that force the gassing or culling of entire poultry flocks similarly cause welfare harm that biosecurity prevents. The welfare argument for good biosecurity is therefore both individual and systemic. Farms that maintain high biosecurity standards protect their animals from disease suffering and reduce the probability of contributing to outbreaks that would trigger widespread welfare emergencies.