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If you have ever pet your dog and felt that they're really warm, you would naturally become concerned. Dogs have a higher body temperature than us humans, so it is common for us to perceive them to be warmer than we expect.
In dogs, normal core (rectal) body temperature is approximately 100° - 102.5° Fahrenheit (38.0° - 39.0° Celsius). Some, normal fluctuations outside this range are very likely during the day.
However, where you need to be careful is when they feel warmer than usual. Core body temperature may become elevated due to pyrexia, the medical term for fever.
More often than not, your dog’s core temperature is normal, but there may be times when they can run the risk developing a fever.
Here’s how you can detect and spot the signs of a fever in dogs.
Generally speaking a thermometer reading of anything higher than 102°F in your dog can be regarded as a fever.
The best way to check your dog's core temperature is rectally, using a digital thermometer.
This should only be done if it is safe to do so. Some dogs may nip if they feel discomfort of having their temperature taken.
Signs of Dog Fever
According to PETMD, here is a list of the clinical signs of pyrexia in dogs (1):
- High core (rectal) temperature
- Increased rate of breathing/panting
- Abnormal behavior
- A decrease in appetite
- Rapid heart rate
How Do Dogs Get a Fever?
The most pertinent question that all pet parents have is what caused the fever?
Finding the culprit behind your dog’s increased temperature may be a little harder to detect. There are so many variables that can contribute to an elevated body temperature.
The first logical assumption of what caused a spike in your pet’s temperature is some sort of a virus or infection. Fever is the body’s way of fighting off infection by making the conditions less suitable for viruses and bacteria to survive.
Evidence suggests that during a fever certain type of immune cells work better at fighting off a virus (2). So in this instance, a fever is the body’s response to an infection and not caused by the infection itself.
Alternative causes for a fever in your dog include:
- Bacterial/Viral/Fungal infections
- Immune-mediated diseases
- Inflammatory diseases
- Drug side effects
- Snake bites
- Allergic reactions
Watch Dr. Sam Meisler, a small animal veterinarian discussing what causes fever in dogs, a very informative and brief video that is worth watching.
Dog Fever Treatment at Home
There is little that can be done for a dog at home with a high temperature other than keeping them as comfortable as possible.
Ensure they are in a cool spot, have access to fresh water and letting them rest is an important first step.
If at any point in time, your dog becomes agitated and there are marked elevations in core body temperature (>103ºF) – bring them straight away to your veterinarian.
Treatment of pyrexia in animals needs to be aimed first at identifying and addressing the underlying cause.
Cooling off your pet is not recommended.
It may work at reducing your pet’s temperature in the short term, but this can also trigger the thermoregulatory center to stimulate heat production and conservation, which is counterproductive.
A fever is a natural defense mechanism so we do not want to eliminate the fever.
How To Diagnose and Treat Pyrexia in Dogs?
Your vet will work to diagnose your pet’s fever with the following tests:
- A thorough physical exam alongside a comprehensive history
- Bloodwork including a complete blood count and chemistry to assess organ function
- Urine testing including a urinalysis and culture
- Infectious disease testing
- Imaging with x-rays, ultrasound scan or even MRI/CT scan
If a definitive diagnosis is obtained, a specific treatment can be initiated.
Treatment options include:
- Hospitalization and supportive therapy for systemically ill dogs
- Immunosuppressive medications in the event of immune mediated causes
- Surgical intervention if necessary
- Chemotherapy for cancerous causes
Final Word on Fever in Dogs
Properly diagnosing and finding the culprit behind your pet’s spike in body temperature is imperative. This can be a lengthy and expensive process.
The problem arises if the veterinarian cannot arrive at a definitive diagnosis. It’s important to find a good and reliable veterinarian that you can trust to work with you. Your beloved pet’s health is important!
You might also like: Explained: Signs of Kennel Cough in Dogs
References and Further Reading:
Saunders Solutions in Veterinary Practice: Small Animal Emergency Medicine, By Shailen Jasani
Canine and Feline Infectious Diseases, by Jane E. Sykes.
"Elevated Body Temperature Helps Certain Types of Immune Cells to work better, evidence suggests", Science Daily.
"Fever in Dogs", PetMD.com