A leading UK vet has issued a winter warning to owners of water-loving dogs over the dangers of potentially-fatal canine hypothermia, as Storm Deirdre threatens to bring a Nordic blast of cold to the UK.

As the weather gets colder so do our rivers and lakes, and while many breeds can cope with close-to-freezing temperatures it can be particularly harmful to others.

Even on a hot day, bodies of water can be cold enough to send a canine’s body into shock, which can cause them to gasp and start swallowing water.

Many pet owners are aware of the dangers of heatstroke, but top vet Iain Booth warns cold weather conditions such as hypothermia are not as well-known.

Ian Booth, the managing director and resident veterinary surgeon at VetUK said: “In summer, we warn about dogs dying in hot cars, in winter the message is very much about staying safe around water.

“A dog’s normal body temperature is around 38.3-39.2°C, and it only has to drop a few degrees to enter the danger zone.

“Mild hypothermia in dogs occurs between 32 and 35°C, moderate hypothermia between 28 and 32°C, and severe hypothermia is anything below 28°C.

“Because most dogs have fur coats, we tend to think of them as being quite hardy and resistant to the cold — even more so than their owners.

“But external factors, like being wet on a freezing day, can cause body temperature to fall quickly, which can be potentially fatal for our pets.

“Cold water in particular can be very dangerous and can send dogs into shock quite quickly. During the winter months it might be advisable to kit out more adventurous of animals with a life jacket, have a thermometer close to hand, and keep them on a lead when close to water.

“If you think your pet is in trouble, whatever you do, don’t dive in to help them. Seeing your beloved animal in distress is horrible to watch but call 999 instead of risking your own life as well.

“Many animals are able to get themselves out of cold water eventually — unlike a lot of humans.”

He added: “If you are worried about your dog after falling into cold water, there are a few warning signs you can look out for such as lethargy, stiff muscles, and pale or grey gums.

“Pet thermometers are available to check your dog’s temperature, so it is handy to have something like that to hand in winter.

“Anything below 35°C should be a cause for concern.”

As in most other animals, hypothermia occurs in dogs when the body is no longer able to maintain a normal temperature. This in turn causes a depression of the central nervous system.

The condition can also bring respiratory, immune and cardiovascular risks.

Founded in 2003, VetUK is a market leader in cost-effective own brand products that are cheaper than big brand high street names.

The company offers an alternative to owners being obliged to take their pets to vets for similar but more expensive treatment.

Growth has been rapid, and in July it recorded its three millionth internet order and grew turnover to £100m.

The business, which employs over 30 people and is a UK licensed supplier of pet medications, sells over 7,500 items.

Full information on VetUK is available by visiting www.vetuk.co.uk