Calculate Dog's Age: Easy Steps for Accurate Estimation

It remains a mystery when or how the "SevenYear Rule" became widespread, but it's believed to be based on the average life expectancies of humans and dogs around the mid20th century. However, this "age rule" could simply be a clever marketing tactic. That's the speculation of William Fortney, a veterinarian at Kansas State University. He suggests that this traditional viewpoint might be a way to illustrate how dogs age much faster than humans, thereby encouraging pet owners to bring their furry friends in for at least an annual checkup.

Challenging the SevenYear Rule

As early as the 1950s, scientists have been seeking a more accurate understanding of a dog's age. French researcher A. Lebeau is credited with defining the various stages of a dog's life. His research on canine adolescence and adulthood revealed that dogs age at a rate of 20 times faster than humans in their first year, with their aging rate gradually slowing down. By middle age, dogs age at about five times the rate of humans.

The SevenYear Rule also overlooks the differences between dogs of different sizes and breeds. Generally, smaller dogs mature faster than larger ones, but they also tend to live longer. Mediumsized dogs fall in the middle on both counts.

The gap between simple sayings like the SevenYear Rule and the reality of canine aging is closely related to the difference between physiological age and actual age. The latter refers to the time elapsed since a person or animal was born, while the former takes into account many factors. For humans and animals, these factors may include genetic traits and lifestyle choices.

Although dogs age faster than us, new research shows that the way their cells age is largely similar to ours. Some scientists believe that the process of DNA methylation (adding methyl groups to certain DNA sequences) is evidence of cellular aging in humans. The authors of this new study suggest that dogs' cells are the same. By examining the methylation patterns in Labrador Retrievers, they have developed a new formula to determine a dog's biological age: multiply the dog's actual age by the natural logarithm of 16, then add 31.

Estimating Your Dog's Age

Many pet owners who adopt pets may not know their dog's actual age. To address this, you can collaborate with your veterinarian to make the most accurate guess and provide proper care. Fortunately, DNA methylation often correlates with additional, more observable changes:

Teeth: Checking your dog's teeth might be the simplest way to estimate its age. Most dogs have a full set of teeth by three months old. They typically start showing signs of tartar buildup and discoloration between three and five years of age.

Eyes: As the lens hardens, older dogs' eyes may start to become blurry.

Coat: As dogs age, gray fur often begins to spread from the nose and mouth to other parts of the body.

Your dog's age will largely determine its medical needs and your pet care costs. So, work with your veterinarian to address daily issues and always be prepared for the unexpected.