Inadequate ventilation in livestock transport vehicles causes heat stress, respiratory distress, and mortality particularly during warm weather.
Livestock transport during hot weather creates acute welfare risks that can escalate to emergency situations within hours. Pigs in particular are physiologically vulnerable to heat — their limited sweat glands, dense body mass, and pack behaviour in transport compartments create conditions for rapid core temperature elevation leading to heat stroke and death. Even non-lethal heat stress causes pain, respiratory distress, and prolonged recovery. Regulatory frameworks that specify maximum temperatures and ventilation requirements exist but enforcement during transport is difficult, and compliance is inconsistent. The welfare risk is predictable and preventable: scheduling journeys outside the hottest hours, ensuring ventilation systems are functional, providing water access, and training drivers to recognise heat stress signs are all achievable improvements that save animal lives and prevent suffering.