A cat's fever of 40 degrees is relatively serious. It is best for parents to take the cat to the hospital for a comprehensive examination to find out the cause of the cat's fever and provide timely treatment. A healthy cat's body temperature will not exceed 39.5 degrees. The body temperature here refers to the rectal temperature. Parents should focus on the rectal temperature when measuring the cat's body temperature.

Tips:

Some cats with minor illnesses usually do not show symptoms. In order to avoid serious causes, parents should pay more attention to their cats and treat them as soon as possible if any abnormalities are found.