No, Your Double-Coated Dogs Aren’t Cooled in the Summer

Have you ever seen a long-haired dog and a short-haired dog in the same vicinity during a scorching summer? The poor long-haired dogs, whether double-coated or single-coated, are panting, trying to take dips in whatever body of water they find, and not running and playing. Meanwhile, the short-haired dogs are running around (unless it’s too hot even for them) and playing.

What does this simple observation tell us? Those dogs with long coats are miserable in the heat and short-haired dogs, while more prone to sunburn, are far more tolerant of it. Still, many groomers, who aren’t veterinarians, by the way, insist that you never, ever shave your dog, especially a double-coated dog.

Why? What’s their reasoning? They claim that the double-coated dogs are actually kept cool in the summer because that incredible top coat traps in the cool air.

Clearly, they failed science class, specifically the parts about thermodynamics.

Let’s take a look at the science and the myths and reality of why people insist you never, ever shave your dog, even though shaving dogs have always, in my experience, produced happier summertime dogs.

The Science

Besides basic observation that says a shaved dog is a cooler dog, we need to look into thermodynamics and basic biology.

People often point to dogs panting as a way of claiming that this is their primary method of thermo-regulating, much like sweating in humans. This isn’t 100% correct, although panting (and sweating in humans) does play a role in keeping cool.

Both panting and sweating rely on evaporation to work. When you sweat, the evaporating water cools the surface of the skin. This can have the nasty side-effect of dehydration, but the cooling mechanism is there.

Panting does the same thing, the gums, mucosa, and tongues are highly vascularized and wet, even if you don’t have a breed that drools incessantly. When a dog pants, the rapid passage of air across these things cools the blood flowing by enhancing evaporation.

Before I get to a caveat of this process, I’d like to point out that in thermoneutral conditions (think room temperature), mammals lose about 70% of their body heat through their skin. This is partially why having even light clothing on will keep you warmer, as you are unable to dispel the amount of heat you’d be able to in your birthday suit.

Even when the dog is panting, such as what happens during intense exercise, 40% of the body’s heat is still lost through the skin. That’s a lot of heat to keep trapped beneath a coat, because, as I’ll explain, it’s not just trapping the cool breeze running through it, it’s trapping the metabolic heat the body is trying to lose.

Moving onto the caveat, panting relies on evaporation to work, meaning in humid conditions, it fails to do its job. When conditions become too humid, it neutralizes this evaporation process and the only way for the dog to effectively lose heat is through the skin. This is why long-haired dogs are more prone to overheating, even after shedding that pesky undercoat. Even the AKC can tell you that heatstroke is more common in long-haired breeds than short-haired ones! So much for that coat trapping in the cold!

That’s not to say that a coat doesn’t trap some cold in, of course. While long coats are designed for blocking out the elements, which includes that cool summer breeze, some will invariably pass through. However, the cooling effect of this is minimal, as the metabolic heat will mix with the hair passing through and rapidly heat it up.

In fact, I read one case of an aging Golden Retriever who’d been diagnosed with heart failure. The poor dog was panting constantly and had no energy, and the owner was preparing to put it down. He decided to bring it to the groomers to see if shaving would have any effect at all, frightened because everyone had warned him never to shave a Golden Retriever because they’d be too hot and the fur wouldn’t come back good. The groomers assured him that it would be fine and that dog left the shop trotting like a puppy. It had more energy and the panting decreased.

These observations don’t just line up with the science I already explained, they line up with evolution as well. Domestic dogs were increasingly bred for looks, even if those looks made the dogs very uncomfortable, such as short hair in cold climates or long hair in hot ones, or those smooshed in faces that keep dogs from breathing well. However, if we look at older breeds, we can still see a pattern of long-haired dogs originating from cooler climates and short-haired ones from warmer climates.

The Chinese crested, for example, was actually bred in Africa. Wild dogs in Africa have short coats, sometimes even losing their fur altogether or in large patches as they age. They simply don’t need it. Were a long coat such a great cooling mechanism in warm climates, canines in such places would all have long coats, but they don’t. They have very little fur.

The Chihuahua and Mexican Hairless dogs, likewise, are warm climate animals.

On the other hand, the Siberian Husky was bred for pulling sleds across the frozen landscape of Siberia. Alaskan Malamutes were also bred for such things, sharing coat traits with northern breeds of wolves. Yes, wolves can withstand summer heat, but everyone who studies wolves admits it’s a challenge. They tend to become inactive and pant constantly, seeking shade and hunkering down.

Even Golden Retrievers were bred to rush into the cold winters of Scotland, not into warm waters off of Florida. Such adaptations are for withstanding cold, not warm.

To sum up, dogs are mammals, not reptiles. They produce their own body heat and that thick coat is trapping that body heat and causing it to heat whatever outside air is coming in and keeps it close to the skin. That would be great for my bearded dragon, not so great for my long-haired pups.

Why Do People Grumble About Those Who Shave Their Dogs?

Despite the science, many people, sometimes even groomers, act like you’ve committed an act of abuse by shaving your dog? Why do so many people spout this “trapping the cold” nonsense as though it’s a law of thermodynamics? Let’s take a look.

They Truly Believe Their Panting, Overheated Long-Haired Dogs Are Cooler with Their Coat

Some people just honestly can’t believe a long-haired dog is happier and more energetic when shaved or cut much shorter than a dog who simply has his undercoat combed out. They won’t look at the actual science because Google decided to forget how the laws of thermodynamics actually work when it comes to how mammals self-regulate their temperature.

They Think They’ll Damage Their Dog’s Coat

This stems from some vanity, but a lot of people are afraid that if they shave their dog, their fur will somehow be damaged. For most dogs, shaving their coats won’t damage the follicles, same as shaving your head won’t ruin your hair, and shaving your body hair won’t cause it to come back thicker.

In some very, very, very rare cases, a dog’s coat may not return to its fullness. This has a small chance of occurring if the dog has an underlying condition. For example, I haven’t shaved my mutt because he has a thyroid issue and it affects his fur. I don’t want to risk cutting it and then having him struggle through the long winters of northern Minnesota.

However, I shaved my Golden Retriever/Chow Chow mix every single summer and every winter her coat returned to its former glory, complete with that amazing black mane that graced her neck and shoulders.

What will happen is that the undercoat and topcoat, if you have a double-coated dog, will grow back uneven for a while because they grow at different speeds. This means your dog will look kind of funny for a while, but this isn’t permanent. Remember, vets shave dogs for surgeries, hot spots, and all manner of things without warning you that your dog could be permanently damaged by said procedure.

In Conclusion

Don’t worry about shaving your dog. You don’t want your dog to be miserable in the heat just as you wouldn’t deny a sweater or a pile of blankets to an Italian Greyhound in the winter. Loads of people do it and their dogs haven’t been damaged by such a thing.