As a dog owner, you may wonder how your sweet pooch handles walking on cold, wet or sometimes even snow-covered ground without hesitation. Until now, no one really understood why dogs are able to tolerate the cold on seemingly poorly insulated paws. Recent research released in the journal of Veterinary Dermatology reveals that although your dog’s paws may lack the fur that protects the rest of his body from cold, the paws actually act as “built-in snow boots” to keep warmth in the body.
Your dog’s legs and paws contain a network of veins that rapidly circulates blood from his foot pads through his lower legs to warm those areas before sending it through the rest of his body. Arteries run right alongside veins inside your dog’s legs, which speeds warming even more. This “counter-current heat exchanger” system also limits the quantity of blood near your dog’s cold skin and pulls warm blood into his paws. This complex circulatory system keeps your dog’s overall body temperature stable and helps protect his paws from damage caused by cold temperatures.
This circulatory network is very similar to the type found in arctic foxes, penguins, and dolphins, although experts are not sure why domestic dogs have this specialized trait. One possible explanation is that domestic dogs evolved from ancestors native to cold climates, according to Dr. Sarah Williams, an anatomist from the Royal Veterinary College.
Research published in the December 2011 issue of Veterinary Dermatology explains that rapid circulation is only partially responsible for your dog’s warm paws. Your dog’s paws also contain abundant fat and freeze-resistant connective tissues that act as insulators, protecting his paws even more from the cold ground. In fact, previous studies have shown that the paws of dogs can tolerate temperatures as low as -35 degrees C.
Of course, this news does not mean you should keep your dog outside all winter long. Dogs are at risk for frostbite and other problems when spending time outdoors in very cold weather. Older animals and sick dogs are at even greater risk due to a higher sensitivity to cold and a lower percentage of body fat. Do not leave your dog outside for prolonged periods during winter months, and follow all safety precautions when allowing your dog outside in wet or snowy weather.