Walking in a winter wonderland takes on a new meaning when that walk includes a dog. Something about snow transforms them into puppies, and even old dogs seem to get a spark of excitement from the frost on their breath. But without preparation, walking in winter can be like, well, walking on thin ice. Thin Ice: Frozen lakes can claim your dog's life. Dogs don't understand the concept of thin ice, just the excitement of being able to walk somewhere that's usually too wet. If the ice is thin enough to break under a dog's weight, chances are it's going to break even sooner under yours. Keep your dog on a short leash when walking around frozen water. Brrrrrr and Grrrrr! Dogs are not immune to the cold. They can get frostbite or become hypothermic, and even die, if left out in frigid temperatures. Several factors affect how well a dog can deal with cold temperatures. Hair: It's not just the length of coat, but its thickness, particularly the amount of undercoat--that's the short, downy hair that lies close to the skin and provides insulation. The long outer coat may repel water, but doesn't add that much resistance to cold. Size: Dogs amass body heat according to volume, and lose it according to surface area. This means that a large, round dog stores heat better than does a small, leggy dog. That's why small, thin dogs are more likely to get cold. Health: Dogs with poor health or nutrition lack the resistance that healthy dogs have. They may also lack body fat, which is a valuable source of insulation. Age: Very young or very old dogs are very likely to lack appropriate fat for insulation, and tend to be more prone to hypothermia. Habituation: Just as with people, when a dog isn't used to cold weather, his body cannot deal with it appropriately. It has not been able to grow the undercoat it needs, and has not been able to mount other vital mechanisms for cold weather. Shelter: Even the hardiest dog needs shelter if he's to spend time outside. That means an enclosed space out of the wind, where his body heat can build up. And even the most macho dog won't mind wearing a sweater or coat on cold days if he's otherwise not equipped to handle the cold. Cold Feet? Even standing around can be hazardous. You may think your dog will enjoy standing in the snow and watching the lighting of the town Christmas tree, but when you force him to stay in one place, he either has to stand, sit or lie down on a cold surface. Bring an insulated pad for him to stand or rest on. Snow and ice can form into little balls inside a dog's paws, so you need to check them regularly. Salt and de-icing chemicals can irritate paws, and could even be toxic if your dog licks them off his paws. You can prevent all these problems by having him wear booties, but most dogs don't care for that fashion statement. Nonetheless, you may need to force those embarrassing booties on him. Either that, or rinse his feet when he comes inside. You wouldn't go out in the cold without taking a few precautions to make sure you're comfortable, safe and warm. Do the same for your dog, and you'll both find yourselves looking forward to snow days and woofing and walking in winter.