Thursday, 12th January 2012
In General Japan News,
Japanese scientists find answer to dog paw mystery
Japanese researchers have uncovered the secret that stops dogs getting cold when standing on frozen ground.
Previous studies have found that dogs can stand on ground as cold as -35 degrees Celsius without the tissues in their feet freezing.
Using electron microscopes to analyse the internal structure of dog paws, scientists in Japan have discovered a specialised circulation system, the BBC reported.
A team led by Dr Hiroyoshi Ninomiya at the Yamazaki Gakuen University in Tokyo found that heat from an artery is passed to a network of veins in dogs' paws, preventing the cooled blood in the paw from returning to the rest of their body.
Dogs' arteries were found to be very close to the veins in their footpad, allowing the heat to be transferred between blood vessels.
This means that the blood cooled as the paw touches the ground is then warmed up by blood pumped from the heart, stopping the dog's body getting cold and keeping the paw at a steady temperature.
It is a system found in many other animals, including the fins of dolphins and the beaks of penguins.
Wolves and Arctic foxes are also known to demonstrate adaptations that have enabled them to maintain warmth in their bodies despite living in often freezing conditions.
Commenting on the findings, Dr Ninomiya told the news provider: "It is well known that penguins in the Antarctic have a counter current heat exchange system in their wings and legs to prevent heat dissipation and keep the body warm.
"When we found that dogs also have such an excellent system in their paws, we were excited."
The results of the study have now been published in the journal Veterinary Dermatology.
The system may come in useful for dogs living in Japan as the winter season is well and truly under way. In the popular ski area of Niseko some ten metres of snow has fallen already.
Written by Kimberley Homer