Nearly 6,600 Farmed Animals, mostly chickens, died from heat stress while being transported to slaughterhouses in England and Wales between June and August 2025, according to a new analysis by Carbon Brief. The figure is more than double the 3,100 recorded over the same period in 2024 and follows a summer with no official heat-related cases at all in 2023. It remains below the 18,500 deaths recorded in summer 2022, when UK temperatures reached 40C for the first time.
The data, obtained from the Food Standards Agency under the Freedom of Information Act, covers “dead on arrival” incidents where vets recorded suspected heat or cold stress as the cause of death. During a heatwave on 11th July 2025, almost 1,000 chickens died in separate incidents, with some showing panting and immobility before death. On 12th August, 2,154 chickens died in heat-stress incidents, with some recorded body temperatures reaching 46C, above the 45C threshold at which a chicken will die, according to a 2005 DEFRA document.
Cold weather has also killed large numbers of animals. More than 13,057 Farmed Animals died from cold stress between December 2024 and February 2025, more than double the 6,981 recorded the previous winter. On 6th February 2025 alone, 4,056 chicken deaths were attributed to cold conditions. The FSA said “dead on arrival” incidents linked to heat or cold stress rose by more than 50% between April 2024 and March 2025 compared with the previous year.
Alex Harman, campaigns manager at Animal Aid, said, “These 6,600 individuals [in summer 2025] did not just die, they suffered prolonged, agonising heat exhaustion inside metal containers — anyone experiencing the UK’s heatwave this week will be able to empathise… Climate change is simply amplifying the violence already built into animal farming… the only compassionate, logical solution is to stop viewing animals as products and urgently transition to a plant-based food system.”
Abigail Penny, executive director of Animal Equality UK, said, “These same scenes of extreme animal suffering play out every summer and, if nothing is done, it’s only going to get worse.”
