Dehydration in dogs occurs when the body loses more fluid than it takes in, and it can be detrimental to their health.
Severe shortage of fluids can lead to heatstroke, kidney and other organ failure, and even death.
Dr Anna Foreman, Everypaw's in-house vet, is urging owners to keep their dogs hydrated in the heat this summer.
She shares her top tell-tale sign your pet needs water - and it only takes seconds to check.
Dr Foreman told The Mirror : "If an animal is well-hydrated, their gums will be pale pink and moist, however, if dehydrated, their gums will be pale and dry."
Sign up to our TeamDogs newsletter for your weekly dose of dog news, pictures and stories.
If you suspect your dog is dehydrated, take a look in their mouth at the colour of their gums.
Dr Foreman continued: "They may also have a skin tent (a prolonged flattening of the skin when it is 'tented' up over their scruff) and sunken eyes."
Another classic test for dehydration is to gently pinch the loose skin at the back of your dog's neck.
A happy and hydrated dog's skin will instantly spring back to its original position.
In a dehydrated dog, the skin is less elastic and will take longer than two seconds to fall back into place.
Heatstroke prevention is key, however, noticing early signs can also save lives.
Dr Foreman explains: "If a dog shows any signs of dehydration, is excessively panting, passes any vomit or diarrhoea, or is weak or lethargic, they should be taken straight to the vets to have their temperature checked.
"In the meantime, active cooling measures (such as wrapping the animal in a cool water-soaked towel) can be put in place - an animal should not have cold water thrown over them as this can lead to shock."
How much water should my dog drink a day?
Dogs should drink between 15-45ml/kg/day on average.
Dr Foreman said: "In the hot weather, a dog will drink more water much like humans, however, rather than sweating they lose water to cool off through panting and so will drink more to replenish themselves.
"Normally this will not exceed the 45ml/kg/day. If a dog is consistently drinking more than this, regardless of the weather, then they should visit the vet as it may be a sign of an underlying issue."
If a dog is seen to be consistently drinking more than their norm - even if it is within this bracket - you should speak to a vet.
Dr Foreman said: "Drinking more water than normal, or urinating more than normal, can be signs of kidney disease and diabetes among a myriad of other conditions."
What breeds of dog are most susceptible to heat?
Every breed needs water equally, however some dogs will get warmer more easily than others and so be more prone to dehydration.
Dr Foreman said: "If a dog is hot they will pant and seek shade and cool surfaces to lie on. Dogs with thick or double coats often pant more to cool off than other dogs.
"If a dog gets too hot it can develop heatstroke - this is when the body’s internal temperature rises above 39.2C due to being in external heat for too long.
"Not only can dogs get heatstroke from being outdoors in the sun, but they are also very prone to developing heat stroke if left in enclosed spaces without ventilation, such as cars and the back of vans, or by being exercised in warm weather."
Brachycephalic breeds, such as pugs and French bulldogs, are particularly prone to heatstroke and so extra care should be taken with these dogs in hot weather, Dr Foreman says.
Additionally, older dogs, as well as those with underlying health conditions, do not tolerate the heat as well as younger healthy ones.
Do you have a dog story to sell? Email nia.dalton@reachplc.com.
