Answer: Like humans, dogs need to keep themselves cool to protect their bodies. They do sweat, but not in the same way. They only have sweat glands only on the paw pads and nose leather. Since they are covered with fur, it is more challenging to keep their bodies cool.
After your dog runs around, you will notice that he begins to pant heavily. Dogs rely on panting to keep their bodies cool. Panting causes the evaporation of water from the nasal cavity, tongue, throat and lungs, which helps lower their body temperature.
They also experience the same dilation in blood vessels as humans, which brings blood to the surface of the skin, allowing the air in the environment to cool them.
Any dog is at risk for heat-related problems, especially in warm, humid weather. Our brachycephalic friends are at a much greater risk than their long-nosed counterparts. Large breeds with thick coats, such as Bernese Mountain dogs or Pyrenees are also more prone. Dogs with pre-existing heart conditions or respiratory issues are also more likely to be overcome by the heat.
When these dogs pant to try and cool themselves, they have to work harder to do so. This only raises their body temperature even higher, making it worse instead of better.