White dog and cat with a fever

Fever in dogs and cats

Having a body temperature that is higher than normal is usually associated with fever. A fever is typically caused by inflammation or infection. A temperature rise is part of the body's normal defence mechanism and fulfils an important function. A rectal temperature above 39.2 degrees C is considered abnormal in dogs and cats. In this article you can read more about symptoms, diagnosis and treatment of fever - and when it's time to contact a vet!

This article was written by a FirstVet vet


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Causes of a temperature

In addition to infection and inflammation, a high temperature can be caused by immunological diseases, traumatic tissue damage, tumours, heat stroke, seizures, allergic reactions, pain, stress or heavy exercise, as well as in response to certain drugs, such as vaccines.

Symptoms of fever in dogs and cats

  • Dull
  • Lethargy
  • Anxious
  • Increased breathing rate or effort
  • Reduced appetite
  • Drinking more
  • Trembling
  • Pinker or redder gums than normal
  • Increased heart rate

Diagnosis - how to find out if your pet has a fever

To know if your dog or cat has a high body temperature, you need to take their rectal temperature. You cannot accurately assess body temperature by feeling the nose, ears, tongue or paw. At rest, the normal temperature is around 38.3 degrees C. It is useful to take the temperature of your animal a couple of times when it is well, so that you know what is the normal temperature for your particular animal.

Tip! Here you can see how to take the temperature of your pet.

Treatment of a fever

If your dog or cat has a mild temperature rise (below 39.2 degrees C) but is otherwise in good health, you can often wait and keep a close eye on them for any other signs that might develop. It may also be a good idea to contact a vet for some advice. Ensure your pet is allowed to rest, stays hydrated and eats small regular meals.

If the animal is showing any of the signs above, or does not start showing signs of improvement, a vet examination is likely to be needed. Blood samples, and x-rays or an ultrasound scan may be the first steps to finding out what the problem is. The treatment will depend on what the cause is. Sometimes, your pet may need to stay at the clinic for monitoring and treatment, such as a drip (intravenous fluid therapy).

Can I prevent infections in my dog ​​or cat?

It is difficult to protect against all infections, just as with humans. Make sure that your dog or cat receives their recommended vaccinations and boosters. A healthy diet and body condition is also important. Knowing what is normal for your pet will help you to spot abnormal symptoms early. Avoid sharing water bowls, food bowls and toys with other animals outside the household will also help to reduce the risk of infections.

Here you can read more about vaccinations for dogs and cats!

When should you contact a vet?

If your dog or cat has a high temperature and is feeling under the weather, or you notice any other symptoms, contact your vet for advice. You can start by booking a video appointment with one of our vets at FirstVet for an initial assessment. If the temperature is above 40 degrees C, you should see a vet as soon as possible.

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