Say It Ain't So Already

How Fido Keeps His Feet From Freezing

January 13, 2012 at 5:49 PM Leave a comment

It’s break time (mostly for dog lovers — sorry kitty people).

As you can tell from the picture above, I’m a dog lover.  (That would be Mr. Albert or “Al,” our now four-year-old English Setter when he was a pup, immediately after he swallowed a mouthful of mud.)  And, being a dog lover, this explains something I’ve wondered about over the years:

Domestic dogs' paws are well suited to the cold

Dogs can keep warm on frozen ground, thanks to a specialised circulation system in their paws, say scientists.

[...]

Arctic foxes and wolves are well known for their adaptations that help them to regulate a constant body temperature in cold conditions.

revious studies showed that the canines can keep the tissue in their feet from freezing even in temperatures of -35C.

Dr Hiroyoshi Ninomiya and his team at the Yamazaki Gakuen University in Tokyo, Japan, set out to discover if this ability was also common to domestic dogs.

Using electron microscopes, the researchers were able to examine the internal structure of dogs’ paws.

They found that the very close proximity of the arteries to the veins in the footpad meant that heat was conducted from one blood vessel to another.

So when blood in the paw’s veins cooled on contact with the air or ground, warm blood pumping from the heart – through the neighbouring artery – transferred its heat.

The blood was therefore “warmed up” before it returned to the body – preventing the dog’s body from cooling down, whilst also keeping the paws at a constant temperature.

[...]

“When we found that dogs also have such an excellent system in their paws, we were excited.”

Anatomist Dr Sarah Williams from the Royal Veterinary College says the evidence could be a revelation for dog experts.

“Up until now, it was not considered necessary for domestic species to posses such a specialisation.

“This discovery has interesting evolutionary implications, and may suggest that the ancestors of the domestic dog lived in cold climates [in order] to bring about such an adaptation.”

Cool interesting.

Entry filed under: Animals (Other Than Us), Break Time. Tags: domestic dogs.