People sweat, dogs pant
Original Publication Date: September 28, 2015
By C. Sue Furman, Ph.D.
Humans and dogs must maintain a constant body temperature to stay healthy. When we get hot, we sweat and are cooled by perspiration evaporating from our skin.
Dogs and cats sweat least of all domestic species.
Instead, dogs pant to cool themselves when they get hot. Dogs, like humans, have two types of sweat glands, but sweating in dogs does not have the same function as in humans.
Humans have apocrine sweat glands primarily located in their arm pits. You know they can perspire profusely when you get hot.
Dogs have similar apocrine sweat glands associated with the hair follicles over most of the body. These secrete a protein-containing sweat when a dog gets hot, but there is too little fluid to get a dog moist.
Canine apocrine sweat glands are not important in temperature regulation.
In humans, eccrine sweat glands cover most of the body but are in highest concentration on the palms of the hands and soles of the feet where the density is estimated to be 3,000 glands per square inch. You have no doubt felt these glands at work on a hot day.
Dogs also have numerous eccrine sweat glands that are present in their foot pads. Like those of people, they secrete a more watery sweat. You have probably seen a dog leave damp paw prints on the sidewalk on a hot day. These glands do not cool the body as a whole but serve to counter rapid rises of temperature on the paw that could lead to burns.
Because a dog doesn't sweat the way a human does, panting with his mouth open is his means of cooling down when he gets hot. This allows moisture on the tongue to evaporate much like sweat evaporates and cools a human. Heavy breathing also carries air over the moist lining of the lungs which serves as a large surface for evaporation and provides significant cooling of the body temperature.
Body cooling is further enhanced in humans and dogs by blood vessels near the skin dilating or expanding. The increased volume of blood that flows through them allows heat to dissipate through the skin. This maintains body temperature as the cooled blood travels throughout the body.
Panting can indicate conditions other than overheating. Dogs also pant when they are excited, suffering from heatstroke, exhibiting signs of some chronic diseases, or are in pain. Consult your veterinarian if your dog exhibits excessive prolonged heavy panting especially if the ambient temperature is at a comfortable level.
Like humans, dogs must maintain a constant body temperature so organs can work efficiently. Sweating is the mechanism we use to cool ourselves when we get overheated. The physiology of the dog is very different. Dogs do sweat but not like us. Instead, dogs pant as the primary way to cool their bodies.
Sue Furman, Ph.D, has published two books and a DVD on canine massage and teaches classes in pet massage, acupressure, first aid and CPR. See her schedule and submit questions at HolisticTouchTherapy.com.