Climate change is increasing the frequency and intensity of heat waves that cause mass mortality events in farmed animals.
Livestock in poorly ventilated sheds during heat waves experience hyperthermia, respiratory distress, and death. Chickens lacking sweat glands are especially vulnerable, with rapid deaths in temperatures exceeding 35 degrees Celsius. Cattle heat stress causes reduced feed intake, compromised immune function, and increased disease susceptibility. The suffering during extreme heat events is acute and mass scale.