Heat is dangerous for more than people

Everyone knows about the dog in a hot car. But the large VetCompass study (Royal Veterinary College, UK) found something unexpected: 74% of canine heatstroke cases come from exertion - walks and play in the heat - and only 5% from vehicles. The most dangerous thing is an ordinary midday walk.

Why the stage decides everything

The same researchers (Emily Hall, Anne Carter, Dan O’Neill) graded heatstroke into stages - and the difference is dramatic: 97% of dogs survive the mild stage, 43% the severe one. Early signs: heavy noisy panting, lethargy, seeking shade and water, drooling, bright-red gums. Late: wobbling, vomiting, confusion, seizures, collapse. The whole job is to act at stage one.

The current protocol: COOL FIRST - TRANSPORT SECOND. A young, healthy dog can and should be cooled with cold water, full immersion included. “Use whatever water you have, provided it is cooler than the dog” - Emily Hall, RVC. What not to do: no wet towels draped over the body (they trap heat - RSPCA), don’t pour over the head, no ice-cold water. Cool it - then to the vet, even if it seems better.

If you have read “tepid water only, or you’ll cause shock” - it is officially outdated: the VetCompass team writes plainly that the advice never had evidence behind it, while delay kills. In 2016–2018 only one British dog in five was cooled before the drive to the clinic - and arrived two degrees hotter.

The asphalt underfoot

At 25 °C air, asphalt reaches 52 °C; at 31 °C - 62 °C (FOUR PAWS). Instrumented measurements in Burns & Trauma add the key fact: at six in the evening after a hot day the asphalt still holds 52 °C - and at 50 °C skin burns in 15 minutes. An evening walk is not automatically safe. The test is simple: press the back of your hand to the surface for a few seconds - too hot for you means too hot for paws. And a surprise from Vets Now: artificial grass gets hotter than asphalt.

Cars, briefly

The classic study in Pediatrics (McLaren, Null, Quinn, 2005): a car interior heats by about 2 °C every 5 minutes, 80% of the rise comes in the first half hour, and even at 22 °C outside it reaches 47 °C inside. Cracked windows change nothing.

Who is most at risk

Per VetCompass, a Chow Chow’s heatstroke odds are 17 times a Labrador’s; a Bulldog’s 14, a French Bulldog’s 6.5, a Pug’s 3. Flat-faced breeds overheat just sitting in the sun. Dogs over 12 are nine times more likely to die of it. Large, overweight and thick-coated dogs are on the list too.

Cats are a different story

Cats handle heat better than dogs - when they have options. A cat panting with an open mouth is not “warm”, it is a warning sign. The real summer trap for cats is not walks but enclosed spaces: sheds, greenhouses, garages and cars they enter looking for shade (International Cat Care). And the sun burns white cats’ ears - real sunburn.

What actually helps street animals

• Bowls deep and narrow - less evaporation; always in shade, refreshed twice a day (Alley Cat Allies).
• A frozen water bottle under the shelter bedding - a simple air conditioner.
• Shelters on earth or grass, never on concrete (it stores heat); two openings for airflow.
• Bared teeth, flattened ears, tucked tail - don’t approach: set water down at a distance and withdraw.
• An animal in bad shape - cool it with water where it lies and call for help.

And one rule for every summer: when the weather service issues a heat warning for people, treat it as issued for animals too. On such days clinics see five times more canine heatstroke (Beard et al., Veterinary Record, 2024).