Dogs Pant Because They Can’t Sweat
Dogs don’t really have sweat glands to help keep them cool, so they have to release excess heat through their breathing. When your dog is panting, he’s trying to regulate his body temperature. If you see your dog panting very heavily, give him a drink of cold water and let him take a rest in the shade.
If it isn’t hot outside and your dog is still panting, he may be trying to relieve pain or stress.