Lethargic dog

Remember when you would feel sick and your mom would place her hand on your forehead to see if you had a fever? It’s not as easy to do that with pets, thanks to their fur coats. But knowing if your pet has a fever can help ensure that he gets needed veterinary care. A high temperature can be a sign of serious illness. Here’s what you should know about fevers in dogs and cats. 

What’s Normal — and What’s Not

An area of the brain called the hypothalamus regulates body temperature. For instance, if the body starts to get cold, the hypothalamus signals the muscles to shiver, helping the body to warm up. If the body is too warm, the hypothalamus directs blood vessels to expand to release heat from the body.

Normal body temperature for a dog or cat is between 100 and 102.5 degrees Fahrenheit. That’s a little higher than normal human body temperature, which is 98.6 degrees Fahrenheit. Interestingly, puppies and kittens have a lower body temperature at birth. They typically don’t reach their minimum body temperature of 100 degrees or higher until they are about a month old.

A fever is defined as a body temperature above the normal range. For dogs and cats, a temperature above 103 degrees Fahrenheit is abnormal.

Infections and inflammation are common causes of fevers. Illnesses such as distemper and parvovirus in dogs and feline distemper (panleukopenia) in cats, tick-borne diseases, immune-mediated diseases, cancer and pancreatitis are just a few of the conditions that can result in a pet developing a fever. In some of these instances, the fever may have a purpose: It can be the body’s way of trying to fight off an infection.

Body temperature can also rise to dangerous levels when pets are exposed to extremely hot or humid conditions. That’s when pets get heatstroke.

Taking Your Pet’s Temperature

Laying hands on your dog or cat won’t tell you if he has a fever but the following signs can be a clue:

  • Lethargy
  • Ears warm to the touch
  • Shivering
  • Loss of appetite

If you suspect that your dog or cat has a fever, you’ll need to take his temperature. Let’s face it: This isn’t going to be pleasant for either of you. It’s a good skill to have, though — knowing a pet’s temperature can help you determine if you’re facing an emergency situation. A rectal reading is most accurate but least “prefurred” by pets. There are a few strategies, though, that can help you and your pet get through it with minimal stress.

You can use either a digital rectal thermometer or the old-school “bulb” thermometer, where you shake down the mercury. Digital thermometers give you a reading more quickly, so they may be the better choice with a fractious feline or cantankerous canine.

If you’re using a bulb thermometer, shake it down until the temperature reads 98.6 degrees. Lubricate it with KY-Jelly or petroleum jelly. If necessary, have an assistant distract your pet at the front end with a wooden spoon coated with peanut butter while you lift the tail and do the dirty deed. Gently insert the thermometer 1 to 2 inches (depending on the size of the pet) into the rectum, twisting as it goes in. Leave the thermometer in place for three minutes, which will seem like a lifetime to you and your pet. Remove it, wipe it off and read the temperature.

For a digital thermometer, read the manufacturer’s directions, then proceed as directed. In most cases, you’re going to insert it as described above.

If your pet’s temperature is higher than 103 degrees Fahrenheit, he has a fever. Never give over-the-counter medications such as ibuprofen, aspirin or acetaminophen to try to bring down a pet’s fever. Over-the-counter NSAIDs made for humans can be toxic and even deadly to cats and dogs. Instead, take your pet to the veterinarian right away.

More on Vetstreet:

  • 5 Ways to Help Your Dog Live a Longer, Healthier Life