Dr. M. Margaret King
EDMOND — Fever is a condition where the internal body temperature becomes elevated, and it occurs when the temperature control center in the brain is reset. This thermostat is in the hypothalamus and is sensitive to what are called pyrogens or chemicals that are fever-producing. These pyrogens may be produced by a variety of agents such as bacteria, viruses, various parasites, fungi, some drugs, trauma that causes tissue damage and by antigen-antibody complexes as a result of allergic/anaphylactic reactions to stings, bites or allergies.
Fever is not the same thing as hyperthermia. Hyperthermia is an increase in the internal body temperature, but it is caused by an internal heat production. This might be from heavy exercise, or being left outside on a hot day with no shade or insufficient amounts of drinking water. Certainly an animal left, for example, in a car in the summer heat would develop hyperthermia.
Normal body temperatures will fluctuate during the day in both cats and dogs and usually will be lowest in the morning and up 1-1.5 degrees in the afternoon and evening.
Normal temperature ranges for dogs are 99.5-102.5 degrees Fahrenheit, and for cats, 100-103 degrees Fahrenheit.
If your pet is not acting right, is depressed, lethargic, not eating or acts achy, it should be checked for a fever. You can check the temperature at home using a human rectal thermometer and K-Y Jelly. Digital thermometers are much faster and easier to use. Wrapping a cat in a large bath towel like a taco will make the chore much easier. If a glass rectal thermometer is used it must be left in for 1-2 minutes.
Some of the digitals will read after only 8 seconds and will beep to let you know they are done. Any temperature above 103 degrees should warrant a trip to your veterinarian as soon as possible.
In cats especially we do not try to give something to simply lower the fever such as aspirin. Tylenol and other non-aspirin products should never be given to a cat as they can result in kidney failure. We prefer to try to determine what is causing the fever and treat the disease if possible rather than just the symptoms.
Fever may be beneficial as it will stimulate the body’s immune system to respond. White blood cells are activated and the body can begin to fight its infection naturally. An exception would be if the fever is 106 or higher. When it reaches such a high level, irreparable damage may occur to the brain and cause seizures.
In the hospital, IV fluids alone can help to significantly lower a high fever while lab work is being run to determine the cause of the fever. Urinalysis, radiographs and specific blood smears or viral tests also can be run. In the rare cases where the fever continues to climb or does not respond to initial treatment, your veterinarian can give appropriate medications, even injections to help lower the fever.
It is always better, especially with cats and small puppies or dogs, to get them to your veterinarian as soon as symptoms appear. The smaller they are the faster they can become dehydrated and this can start a downward spiral. Never wait to visit the pet hospital when a pet has a fever and shows signs of not feeling well. Early care is easier, less expensive and better for the pet’s health.
DR. M. MARGARET KING, a longtime Edmond veterinarian, is a guest columnist. If you have any questions, send them to 1900 S. Bryant, Edmond, OK 73013.
