Extreme temperatures during livestock transport cause severe welfare harm and mortality that appropriate management can substantially reduce.
Animals in transport vehicles during extreme heat experience rapidly escalating physiological stress from inability to thermoregulate in crowded conditions. Pigs are particularly vulnerable as they cannot sweat efficiently and at high temperatures produce metabolic heat that further elevates vehicle temperature. Death from heat stress occurs through hyperthermia, cardiovascular collapse, and organ failure preceded by prolonged severe suffering. Winter transport of young, thin, or recently shorn animals causes hypothermia and cold stress that compromises immune function and causes distress. Temperature monitoring and active cooling or heating systems in transport vehicles represent proven welfare investments that also reduce mortality-related economic losses.