Heavy Panting in Dogs - Pets - WebMD http://pets.webmd.com/dogs/dog-panting-heavily WebMD: Why is My Dog Panting Heavily? Web MD: Why Is My Dog Panting Heavily? WebMD: Why Is My Dog Panting Heavily? WebMD: Why Is My Dog Panting Heavily? WebMD: Why is My Dog Panting Heavily?