How much water should your dog be drinking in hot weather?

As temperatures start to rise across the UK and as we head into summer, Dr Anna Foreman, vet at Everypaw Pet Insurance, advises how much a dog should be drinking in hot weather - and how to tell something may not be right.

Dogs should drink between 15-45ml/kg/day on average. 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.

Equally, if a dog is seen to be consistently drinking more than their norm, even if it is within this bracket, a vet visit is also recommended. Drinking more water than normal, or urinating more than normal, can be signs of kidney disease and diabetes among a myriad of other conditions.

If a dog is thirsty it will tend to seek out water. If this is not readily available to them then they will drink from any source - puddles, streams etc. We do not know the quality of this water, for example, how dirty it is and whether there are any chemicals in it, so drinking water should always be made readily accessible to animals both at home and on the go.

There are plenty of portable water devices for animals now on the market. There is also the risk of ‘wild’ water being contaminated with rat urine, which can harbour leptospirosis. This can be a deadly condition if contracted by a dog. Fortunately, it can be vaccinated against – it is recommended to keep your pet's vaccinations up to date regardless, however, especially if they are frequenting woods or fields.

We can tell if our dogs are dehydrated by looking at their gum colour and hydration – if an animal is well hydrated their gums will be pale pink and moist, however, if dehydrated their gums will be pale and dry. They may also have a skin tent (a prolonged flattening of the skin when it is ‘tented’ up over their scruff) and sunken eyes. Every breed needs water equally, however, some dogs will get warmer more easily than others and so be more prone to dehydration.

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 39.2oC 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.

Some breeds of dogs cannot tolerate the heat, and particularly exercising in the heat, more than others. 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. Additionally, older dogs, as well as those with underlying health conditions, do not tolerate the heat as well as younger healthy ones.

Dogs, in general, should not be exercised in the middle of the day in warm weather – instead, the cooler early mornings or evenings are far safer. A dog won’t die from missing one walk, however, they can if they go for one in hot weather!

Heatstroke prevention is key, however, noticing early signs can also save lives. 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.

This is a guest post by Dr Anna Foreman.