Hot to trot: does your dog really need a jacket in the Australian winter?

As a vet who works on Melbourne’s northside, Dr Kate Golaszewski sees a lot of well-dressed – and overheated – dogs come into Lort Smith animal hospital.

“Most of the time the dogs that I see wearing coats don’t need them,” she says. “You’ll get a fluffy Maltese coming in with a coat – it probably doesn’t need it cause it’s covered in fur.

“You’ll rarely find a dog that enjoys wearing outfits and paraphernalia. [And] they don’t particularly like having their heads covered with a hoodie.”

Fashion can be a sensitive subject for some dog owners, who understandably find it hard to resist cute canine outfits (the global pet clothing industry was valued at US$5.56bn last year and is projected to reach $8.97bn by 2032).

Related: Pet hates: what’s it like to dislike dogs in a dog-loving country?

And as temperatures plummet this winter across southern Australia, it’s natural for dog owners to be concerned about their pet’s comfort.

But, says Golaszewski, owners should take into account a dog’s breed, size, age, hair density and activity level before slapping on a jacket.

“For small breed dogs with short fur – such as Italian greyhounds or short-haired chihuahuas or Chinese crested dogs – it’s certainly not unreasonable to have them wear coats on really cold days,” she says.

“They have a larger body surface area [to mass ratio] and so they’re more prone to losing heat than a large breed dog.

“But for most dogs – say your average labrador – [they] shouldn’t need to wear coats unless they’re really old and not terribly mobile, and if they’re really skinny [they] can be more prone to heat loss if all they’re doing is sitting around in the back yard.”

Should my pet wear a coat to the dog park?

When running around in the park in Australia, dogs don’t need jackets, says Golaszewski – and this includes greyhounds.

The exceptions, she says, are elderly dogs with reduced mobility. Her own pet Italian greyhound would venture out jacketless when it was young. “Nowadays, she’s 15 and her walks are very slow and all she’s doing is sniffing and snuffling around, so she will wear a coat on some of her walks,” Golaszewski says.

“But the thing with coats is, you’ve got to make sure they’re not overheating or getting humid and sweaty.”

How can I tell if my dog needs a jacket?

Di Evans, senior scientific officer at RSPCA Australia, says you can discern whether a dog is cold by observing its behaviour.

Uncontrollable shivering and cold ears are obvious signs, as is “curling up in a really tight ball”.

“When they’re burrowing their nose under their hind legs, they are minimising their surface area being exposed to a cold temperature,” she explains.

Larissa Hubbard, the adoption manager of Greyhound Adoption Program Victoria, has specific advice about greyhounds because they are thin-skinned with fine coats and low body fat. “We usually tell our adoptees, ‘If you’re cold, your dog is probably cold’ … We recommend they wear a coat when they’re outside in winter.

“If they’re struggling to hold their weight … or if they suddenly start urinating inside at night when they’ve previously been clean, it can also be a sign they’re cold.”

On nights when it dips below 10C, Toni Donnelly, the chairperson of Greyhound Adoptions Western Australia, recommends greyhounds wear pyjamas or coats indoors to help regulate their body temperature.

“Some of [these outfits] have legs, some of them are onesies, and some of them are simply coats with ties at the back. They can be very elegant looking.”

Evans says small dogs with long hair, such as west highlands terriers and Maltese, generally don’t need rugging up, however owners should let their hair run wild in the winter. “The danger time for them would be if they get their coat clipped,” she says.

I don’t think I’ve seen a single dog present [at the animal hospital] with hypothermia because it wasn’t wearing a coat

Dr Kate Golaszewski

For most breeds, Golaszewski says, “If they’re indoors and they’ve got a basket with a blanket, there shouldn’t be a need for them to wear coats.”

Is my dog too cold in the back yard?

A cold dog will display “shelter-seeking behaviour”, says Evans.

“They’ll seek shelter somewhere out of the wind – in a bit of shrubbery or under the house if there’s space there. If there’s two [dogs] they might cuddle up together, and sometimes they might even dig into the ground … They’re almost making a bed in the earth to keep warm.”

Golaszewski advises owners provide their pet with a kennel and blankets if it spends extended periods in the yard in winter.

How can I tell if my dog is comfortable in its jacket?

The first time you put a jacket on a dog it’s important to ensure it’s a “positive experience”, says Evans. “Give them rewards and reassurance, and make sure it’s not too tight or loose.”

Fabric should also be a consideration: soft on the inside and waterproof on the outside.

Golaszewski is more wary: “I don’t think I’ve seen a single dog present [at the animal hospital] with hypothermia because it wasn’t wearing a coat.”

Related: Is my dog too cold? How cold is too cold for a walk? Here’s how to tell

An overheated dog will display clear signs of stress, she says. “Most dogs will just try and immediately rub [the jacket] off or scratch themselves or pull it off with their mouths.”

Others will “pant, not be as active as they normally would, lip-lick and yawn”.

Evans notes an overheated dog may lie down and stretch out “to try and maximise body surface area to have the heat dissipate as quickly as possible”.

My dog is a sook about getting wet. Does it need a rain jacket?

Not all canines love to walk in the rain – and most owners aren’t enamoured with wet-dog smell either.

But are rain jackets the obvious solution? “Rain jackets are fine,” Golaszewski says , but cautions: “Again, most dogs will find them too warm once they get moving.”