PEOPLE should not leave their dogs in cars or any enclosed spaces this summer, warned Swan Hill veterinarian Mary Slater.
"In the hot weather, it's not just vehicles that can cause heat stress but any form of enclosed space including verandas or dog boxes on trucks," Dr Slater said.
If a dog is left in an enclosed environment with no ventilation and lack of water it can overheat and collapse, Dr Slater said.
It comes after a number of dogs were observed left in vehicles parked on Campbell Street on Wednesday.
"Heat stress can lead to brain, liver and kidney damage and your dog may never be the same again," Dr Slater said.
The warning signs of a dog overheating are excessive panting, drooling and becoming restless.
According to the RSPCA, it takes just six minutes for an animal to die in a hot car, however Dr Slater said there are many factors that can exacerbate the situation.
"It depends on a number of factors including age and breed of the dog," she said.
"A big shaggy breed of dog won't cope as well as a little, short haired foxy terrier."
Ms Slater said in order to avoid heat stress in pets, never leave animals alone in an enclosed space and always ensure they have plenty of cool water.
"If you must leave, make sure you get someone to check on your dog," she said.
"You can put ice blocks in the water and situate them in a shady area with a cool breeze."
Dr Slater said a good rule of thumb for testing the outdoor temperature is the five minute test.
"The five minute test is if you can't put the back of your hand on an outdoor flat surface for more than five minutes then it is too hot to walk your dog," she said.