It seems like the most natural thing in the world to take your dog to the beach for a quick dip on a hot summer day, but veterinarians are warning that it could be hazardous to Fido’s health.

“Some believe that dogs are very hardy, but dirty water can easily tear up stomachs,” Jens Filrups, a vet at Odense Animal Hospital told DR Nyheder. “ They vomit and have diarrhoea, and when it's hot already, they dehydrate and things can quickly go very wrong.”

Filrups said that owners should only let their dogs swim in clear water.

“It may be small lakes, marshes or even the bird bath at home, but algae in the water can wreak havoc on a dog's digestive system.”

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The rule of thumb is to only let the dog swim in or drink water that the owner themselves would use.:

“Keep your dog from water that looks green or stagnant,” he said. "It should be water that you would be willing to jump in.”