Inadequate ventilation in livestock trailers causes heat stress, respiratory distress, and death during transport, particularly in warm weather and with dense loading.
Livestock transport ventilation is a critical welfare variable that interacts with loading density, journey duration, ambient temperature, and vehicle design. In warm weather, even brief journeys in poorly ventilated trailers with dense loading can cause heat stress that causes distress, immune suppression, and in extreme cases death. Modern livestock transport regulations include ventilation requirements, but enforcement is inconsistent and vehicle inspection is infrequent. Driver training in recognising heat stress signs and emergency responses is an important welfare safeguard. Technological solutions including on-board temperature and humidity monitoring with alerts are increasingly available.