Friday, March 4, 2016
Researchers demystify the secret on how a dog's paws tolerate cold and snow
It's been a mild winter across much of the Midwest in comparison to those in recent past. That despite the snowy weather we've experienced here in Michigan so late in the season. So clement in fact that it has resulted in far fewer days where I've needed to be extra-creative with indoor play for my charges because of the bitterly-cold temperatures.
It's no doubt that the winter weather can wreak havoc on our outdoor fun, and that of our canine friends. Their paws are a special consideration because they have direct contact with the ground.
I'm seeing the use of dog booties more often. And, since I work professionally with animals, I'm asked about my opinion on them. It seems that though a lot of dog owner's gut instinct is telling them that using booties doesn't seem necessary, they feel like they might not be doing the right thing by forgoing them. They admit part of it is due to peer pressure, which is unfortunate.
I have to say that for the most part, I find dog booties unnecessary. But before you scoff at my stance, allow me to explain.
In my experience, the biggest problem with the booties is that they don't fit well. Unless you have nice clunky ankles like a Great Dane, no matter how the booties fasten they don't stay on. And if they don't stay on, the protection that they're intended to offer isn't there, right?
Speaking of which, the theory on what booties are designed to do is two-fold: they are supposed to protect a dog's paws from salt and ice melter as well as the elements (namely the cold).
The former is a valid concern, no doubt. I find that in some areas – especially in neighborhoods and on city sidewalks – there's an abundance of product scattered about that can be irritating to a dog's paws. Whether it's the texture or the chemical itself that causes discomfort, dog booties (Pawz brand is tops in my book) can be a boon in keeping pets marching on. Musher's Secret is a nice choice, too.
In my years chaperoning pets on outdoor adventures and gauging their behavior during and after, there's no indication – barring the below-zero temps that we occasionally see here in Michigan – that their paws experience discomfort from the cold. Why that's the case is supported by findings by researchers out of Japan.
To begin with, dogs' pads contain lots of fatty tissue. This area doesn't freeze as easily as other tissues, and the blood vessels in dogs' feet are arranged in a way that's unique: they let them serve as living heat exchangers — arteries in the paws are very close to networks of tiny veins, and these allow the transfer of heat from venous to arterial blood.
The research was conducted by Dr. Hiroysho Ninomiya and other scientists at Tokyo's Yamazaki Gakuen University. An electron microscope and four subjects were used to help do the study, which was published in the journal Veterinary Dermatology.
A "counter-current" heat exchange occurs like this: a paw is cooled by contact with frozen ground, and warmth from the arteries in the paw gets transferred to the tiny veins, called "venules." This helps keep the paw at a manageable temperature. It also warms the blood before it flows back to the body, which helps keep the dog's body temperature from falling too low.
This isn't an ability that nature has given only to canines. Penguins and foxes, have it, too.
The information in the study suggests that dogs may have evolved in cold environments, but this doesn't mean that they should be left out in the elements.
Some pets can be more sensitive than others when it comes to the cold and their paws. If yours is one of them, it's always wise to use your best judgement to help them stay comfortable.
Lorrie Shaw is a freelance writer and owner of Professional Pet Sitting. Shoot her an email, contact her at 734-904-7279 or follow her adventures on Twitter.