How to Know the Life of a Cat
When you adopt a cat from a shelter or deviate from it, it is usually impossible to know the exact age of your new family member. Of course, there is a clear difference between a kitten and an older cat, but for the inexperienced eye, the intervening years may seem a lot. It is likely that you bring her to a veterinarian, who will perform a physical examination and perhaps perform some tests to help determine the approximate age of your kitten. But what exactly do doctors look at? And how accurate are your estimates?
For more information, we spoke with Dr. Erick Mears, medical director of BluePearl Veterinary Partners in Florida, and Dr. Rachel Barrack of Animal Acupuncture in New York City to find out how experts determine the age of a cat.
How old is my cat? The perspective of a veterinarian
Because each animal matures at a different rate, even veterinarians have trouble knowing for sure how many years, months and days a cat has been on the planet. However, they can make a very educated guess.
"When I give someone an estimate about their cat's age, I tend to start by looking at the teeth," Barrack said. Teeth can be strong indicators of a cat's potential age, especially in younger animals. Usually, a kitten's baby teeth begin to appear when they are about three weeks old, and all 26 are present when they reach six weeks of age. The ages between three and six months can be determined by the speed at which the milk teeth are falling and their permanent replacements are entering.
If veterinarians see a full set of adult teeth, they generally assume that the cat is at least six months old, and if those teeth are clean and sharp, it is likely that the cat is less than two years old. After that, however, things can get murky. "Beyond two years it becomes much more difficult to tell the age of the cat by its teeth," Mears said.
After looking at a cat's teeth, doctors then examine the shield and the muscular system for more clues. Younger cats often have bright coats and strong muscle definition in the legs and back. Around 10 to 14 years old, cats may start having problems digesting proteins and fats and, as a result, may have reduced muscle mass and lose weight. Older cats also have a high risk of developing arthritis that limits their mobility and ability to groom themselves, resulting in fur that becomes opaque and matted.
Beyond physical examination, lab work on older kittens can help veterinarians determine a patient's age. Kidney problems can appear around ten years, and hyperthyroidism indicators a year or two later, however, Mears said he has seen them in cats up to six years old or as old as 22.
So, how much time is a year of cat in human years?
Once you know approximately how old your kitten is, you can compare her age with yours. It turns out that the ratio of cat years to human years is not as simple as a single conversion rate; Cats develop faster during their first two years of life and then slow down. Then, at the end of your first year, your cat is approximately in the same stage of development as a human 10 or 15 years old, and for two years, your cat will have about 25 in human years. "After that, cats tend to develop more slowly," Barrack said, aging about four or five human years every 12 months.
Putting your pet's age in human terms not only helps you empathize with your cat, it also shows the importance of regular veterinary checks. "A one-year time frame in the life of a cat is significant," says Mears. "Things can change drastically." If a year of adult cat is equivalent to four or five human years, it is easy to see how arthritis could develop, it could decrease organ function and neurological changes could develop in a seemingly short period of time.