People fight the cold with heavy coats, long underwear and wooly mittens. And if it's too cold for people, a fur coat won't protect pets from weather extremes, either. Just like people frostbite and human hypothermia, pets also can suffer from cold weather dangers, including frostbite and hypothermia.
Dogs and cats protect themselves by curling up in small shelters that can be warmed by their own body heat. Fluffed fur insulates the body the same way clothing protects people -- by trapping warm air next to the skin.
But wind strips away the protective layer of warm air trapped by fur. Getting wet makes the cold worse, when fur can't fluff to hold warm air. Even moderately cool temperatures can be dangerous. A 20 mph wind makes 40 degree weather feel like 18 degrees.
How Pets Stay Warm
Adult dog and cat body temperature ranges from about 100 to 102.5 degrees Fahrenheit. Puppies and kittens, though, have trouble maintaining body temperature. Huddling together shares warmth and reduces wind loss of heat, and shivering generates heat.
Short-haired pets have less protection but even wooly cats and dogs are at risk. Thinly-furred areas or body parts exposed to the wind or that come in contact with the icy ground have little protection from the cold.
Pets conserves heat by diverting blood circulation from the ear tips, toes and tail to protect the vital organs in the central part of the body. But reduced circulation to these extremities increases the chance for frostbite.
What Is Frostbite?
Tissue is 90 percent water. When frozen, cells rupture when the water expands just like ice cubes overflowing the tray. The resulting damage -- termed frostbite -- can be painful and severe.
Frostbite turns the skin pale white, gray or blue. Fur may hide the damage, but you'll notice pets limp from frozen toes, frozen ear tips or tails droop, and the skin will be very cold, hard and nonpliable.
Redness, blisters and serious infection develop days later. If it's really severe, the affected tissue turns leathery and insensitive to sensation. If not removed surgically, those areas fall off. All cases of frostbite need veterinary attention after first aid.
Frostbite First Aid
Pet first aid is similar to first aid for human frostbite. Thaw frozen toes or tails by dunking them in lukewarm water. Thaw frozen ear tips or scrotum with a warm wet towel held against the skin. Don't rub as that makes the damage worse and reduces any chance of recovery.
Tissue that's completely frozen may take up to 20 minutes to thaw. Less deeply-frozen areas turn bright red as they thaw. Apply an antibiotic ointment like Neosporin to the oozing area to help protect against infection, until your veterinarian can treat the pet.
Mild frostbite usually resolves within a week or so. Antibiotics, pain medication, bandages or even surgery to removed damaged or dead tissue may be necessary. It may take several weeks for the damage to completely heal.
What Is Hypothermia?
While frostbite causes discomfort and damage to the extremities, hypothermia happens when overall body temperature falls below normal. In people hypothermia is defined as body temperature lower than 95 degrees, and treatment is vital to survival. When body temperature falls too low in pets, they can die.
Hypothermia First Aid
Mild hypothermia happens if body temperature drops to between 95 to 99 degrees Fahrenheit. Pets act a bit sluggish and lethargic, and you'll see muscle tremors and shivering that serves to rewarm the body. Just bringing the dog or cat inside where it's warm usually allows him to recover.
Moderate hypothermia is more serious when the temperature falls to 91 to 95 degrees. Offer warm chicken broth to heat up the pet from the inside out. Wrap him in a towel or blanket heated in the clothes drier. It takes pets longer to recover from moderate hypothermia, but if he's able to shiver, he should recover.
Severe hypothermia is body temperature 90 degrees or less, and is an emergency -- take your pet to the veterinarian as soon as possible! Pets lose the ability to shiver if their body temperature falls to 90 degrees or below, so that's a warning sign. They may fall unconscious, and rescue breathing may be necessary. Veterinary treatment may include warm intravenous fluids, warm water enemas or airway rewarming using oxygen.
The best protection against people frostbite and hypothermia is to provide shelter from the wet and cold. The same holds true for pets. Bring cats and dogs inside during severe cold. Why not snuggle together, share body heat and protect each other safe from Old Man Winter's dangers?
Amy D. Shojai, CABC, is a certified animal behavior consultant and the award-winning author of 23 pet care books. She also writes for puppies.about.com and cats.about.com and appears on Animal Planet's CATS-101 and DOGS-101. Check out Amy's latest book, "Pet Care in the New Century: Cutting-Edge Medicine for Dogs & Cats" and on Red Room, where you can read her blog and buy her books.