The popular practice of feeling a dog’s nose and ears to see if he has a fever doesn’t work. The only way to know your dog’s temperature with any degree of certainty is to use a thermometer.

What to use to take your dog’s temperature: Thermometers made specifically for pets are available for about $12. Veterinarian Kelly Tart recommends using a rapid-reading digital thermometer, which can record a temperature in about 10 seconds and has an easy-to-read lighted display screen. Do not use a glass thermometer; they can break, and some contain mercury.

Where to take your dog’s temperature: The most accurate place to take a dog’s temperature is the rectum. Ear thermometers can be inaccurate because they do not reach far enough into the ear canal, Dr. Tart says.

How to take your dog’s temperature

1. Have someone help you by holding the dog’s head and body. Lay your dog on his side to keep him from sitting on the thermometer.

2. For easier insertion, coat the thermometer’s end with a lubricant, such as Vaseline or K-Y Jelly.

3. Insert the thermometer about 1 inch for small dogs and 2 to 3 inches for medium and large dogs. Go slowly, and never force the thermometer.

4. Gently remove the thermometer when it beeps.

If your dog protests too much or you are uncertain or uncomfortable about taking your dog’s temperature, it’s best to have your veterinarian do it.

Top photograph: Ocskaymark| Getty Images

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