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​Taking Your Dog's or Cat’s Temperature Rectally

It is important to know that unlike people, dogs and cats don’t necessarily become warm when they have a fever, so feeling your animal’s head, ears, or nose for heat doesn’t necessarily give any indication of his/her internal temperature.

There’s no correlation between nose temperature and moisture and an animal’s overall body temperature or health. The only way to tell accurately if a dog/cat has a fever is to take his/her temperature the good old-fashioned way…with a thermometer…and take it rectally.

You can use either a digital or mercury oral or rectal thermometer. You don’t need to buy one that’s specifically for animals.

If you use a mercury thermometer, shake it by flicking your wrist until the mercury is below 94 degrees Fahrenheit.

If you use a digital thermometer, turn it on and wait until the 188.8 turns to L.

1. Lightly lubricate just the tip of the thermometer using a drop of an edible oil.  If you have my CLO-3-Pearls, you can clip one of the soft gels and use that oil.  If not, olive oil or any edible oil is fine.

2. You may or may not need a second person to help, depending on how cooperative your animal is.  The person helping you should tightly hug your standing animal, holding his/her head and putting her hand on the underbelly of your animal so s/he cannot sit down.

If you do not have help, you can lay your animal on his/her side on a table that is waist high, and then for control, bend over your animal, so that the top of your body is gently covering him/her which allows you to have both hands free. 

3. Lift your animal’s tail and slowly insert the thermometer about an inch into his/her rectum, which is directly below his/her tail. If you’re using a mercury thermometer, hold it in place for two minutes. For a digital thermometer, wait until it beeps.  If the digital thermometer doesn’t beep, or you are using a mercury thermometer, and it has been inserted for two minutes, that will be the body temperature.

4. Remove the thermometer and read the temperature. A dog's/cat's normal rectal temperature is 101.5 Fahrenheit or 38.6 Celsius.  If it ranges between 100.5 and 102.5 degrees Fahrenheit or 38 and 39 Celsius, then your animal is not in serious trouble.  Anything higher or lower than that, you need to contact me right away and let me know what else is transpiring with your animal.

Do not clean the thermometer by putting it in hot water…or any temperature water.  Clean it by using a tissue soaked with alcohol or hydrogen peroxide.

I do not recommend an ear thermometer; they are not accurate, and if you don’t know how to use it correctly, you can do damage to your animal’s ear.