Biosecurity measures that prevent disease introduction onto farms protect livestock from infectious disease and the welfare harm that disease causes, representing a welfare investment as well as an economic one.
Biosecurity and animal welfare are directly aligned: disease that enters a farm causes suffering in the animals infected and often triggers mass culling that causes suffering in uninfected animals too. A single African swine fever introduction can result in all pigs on a farm being killed under emergency disease control powers — welfare harm of catastrophic scale triggered by preventable biosecurity failure. The welfare case for farm biosecurity investment is therefore clear and direct. Biosecurity measures themselves can have welfare implications when implemented poorly — entry protocols that stress animals, vehicle disinfection procedures that cause contamination — but well-designed biosecurity is welfare-positive at every level. Extension support for smaller farms to implement evidence-based biosecurity is a welfare intervention with strong multiplier effects.