It's a myth that you can tell your dog's temperature by checking out his nose; a wet nose doesn't mean all is fine, and a dry nose doesn't mean he's got a fever. The only way to know for certain is to take his temperature.

"We use the human digital thermometers at the vet school," says Dr. Sandi Sawchuk, clinical instructor at the University of Wisconsin School of Veterinary Medicine. "The ones with the flexible end are safer." Don't use a mercury thermometer, which may break inside your dog's body, causing serious harm, or a digital ear thermometer.

"Ear temperatures are unreliable in dogs due to the shape of their ear canals -- you need to be close to the eardrum for a reading," says Sawchuk. "Also, dirty ears or hairy ear canals will affect the accuracy."

First, enlist the help of one other person to hold your dog's head. Then, after putting petroleum jelly on the thermometer's bulb, insert the thermometer about an inch or two into the rectum, depending on your dog's size. Hold the thermometer in place for about 60 seconds, or until the thermometer beeps, then remove gently and read.

If your dog's temperature is elevated, but not dangerously high, have him drink small amounts of water regularly to stay hydrated, but never force him to drink. And certainly don't give him fever reducers designed for humans, since they may be poisonous to a canine. If your dog's temperature is elevated due to excessive heat or exercise, this is a slightly more serious situation, and you need to act quickly to prevent his condition from progressing to heatstroke. Get him out of the sun and heat immediately, then apply cold cloths and/or ice on his body, especially the feet and ears.

If your dog's temperature is low (hypothermia), keep him warm with blankets and hot water bottles, plus minimize his activity. A heating pad applied to his torso may help, too, but if you use one, make sure to wrap it in a cloth first to prevent accidental burns.

Even if your pet doesn't appear sick, make sure to check in with your vet if his temperature stays elevated or low. While you may think you know what his problem is -- an ear infection, for example, or too much time playing in the snow -- there could be something else going on.