Cooling off summer heatIn the first four days of last week the RSPCA fielded 729 calls related to animals being left in stifling conditions.

Local and national newspapers are reporting deaths of previously fit and healthy dogs from heatstroke not from being left in cars, but as the result of walks.

But if you google information on maintaining healthy temperatures for your canine friend, UK sites offer information on avoiding the cold. So we thought we share some of the summer science from around the world.

Why you should never leave a dog in a summer car

In the summer a car is like a greenhouse. The sun warms up the temperature inside by heating the dark areas which themselves then release that heat into the air. This has nowhere to go so keeps getting hotter. At 24°C outside, the car inside can be 38°C and within half an hour 50°C.

There is no exact science on how cars heat up as internal colour, material and external shading and humidity will affect it, but a typical range is below, where the outside temperature is 21°C or 70°F
Minutes                  10   20   30   40   60
Temperature °C    32   37   40   42   44

Now consider that:

  • a dog’s body temperature is typically 38.3-39.2°C, so already hotter than humans’ 37°C
  • dogs have sweat glands only in their feet and nose, so find it difficult to shed heat.
  • when a dog’s internal temperature passes 41.5°C, things become critical.
  • the big temperature spike is in the first 20 minutes from 21°C to 32°C
  • the difference in temperature rise with having a partly opened window is only 0.15°C every 5 minutes so useless in keeping the temperature down.

It becomes clear why dogs must never be left in summer cars.

Walks Can Be Good?

Dogs need exercise and walks are good with a little care. Walking in the cool parts of the day are good for both of you particularly if you think of the surface you’re walking on. We have all probably walked barefoot on hot sand and finished cooling off in the sea. But it’s not always that easy.

A simple test is to put your hand on the surface and try to hold it for 7 secs. If you can’t do it easily don’t walk on it. There are no prizes for gripping on to get your hand burnt. Typically 1 minute at 52°C will destroy skin and burn footpads. Sadly at 25°C with no wind and low humidity, tarmac can often be 52°C. This is unfelt through the soles of our shoes, but not by our loyal friend. Artificial grass is often higher still at 59°C but natural grass is 36°C and concrete usually 41°C. So opt for grassy walks in shaded areas.

Note that tarmac retains its heat after the sun goes down when it sheds the heat into the air. So where possible consider a morning rather than evening walk as the air temperature may be similar, but the ground temperature very different.

Heatstroke in Dogs

If your dog is panting or drooling excessively, is lethargic, drowsy or unco-ordinated or worse is vomiting or collapsed then they may be a victim of heatstroke. If so:

  • Take your friend to a cooler area and if necessary damp the area down to reduce the air temperature
  • Spray him with cool, but not ice cold water and then fan him
  • Give him small amounts of water to drink
  • When his breathing has normalised and well before he is shivering with cold take him to the vets for a check-up.

For more advice on heatstroke check out the RSPCA. And better still be sensible in the hot weather with cool walks and never leaving your friend in the car.