Dogs do not sweat like humans, from the surface of their skin, to regulate their body temperature. Instead, dogs open their mouths and pant to reduce their body temperature. Contrary to popular belief, it is not the act of releasing saliva that cools down a dog. Panting allows oxygen into the body and helps evaporate moisture on the tongue, which reduces the dog's body temperature. When feeling overheated, dogs might also release excessive moisture through the pads of their feet to cool down. Dogs also can reduce their body temperature by having the blood vessels on their faces and ears dilate, which results in blood drawing closer to the surface and becoming cooler.
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