This study and research project started at Princeton University, New Jersey in 2018, and it is expected to run for at least 10 years. It hopes to give veterinarians and scientists the tools to understand healthy ageing for both dogs and people. It is partly supported by the National Institute of Ageing.

Given that dogs share the human environment and they have access to a sophisticated health care system, but they have a much shorter lifespan than people, they offer the unique opportunity to identify the genetic, environmental and lifestyle factors associated with a healthy and long lifespan. The DNA of exceptionally long-lived dogs is being analysed, along with sequencing genomes of 10,000 dogs. Canine citizen scientists are also involved, with more than 32,000 dog owners joining the Dog Ageing Project. Dogs of all ages, breeds, mix-breeds and sizes are being recruited, and the owners agree to fill out annual surveys and take measurements of their dogs for the duration of the survey. Some collect cheek saliva swabs for DNA sampling. In addition, the team works with vets across the country who assist by submitting fur, faecal, urine and blood samples of selected participating members.

For years it has been generally accepted that dog years are roughly seven times that of humans, so a ten-year-old medium size dog would be about the equivalent of seventy, but it is actually much more complicated than that. Scientists are now saying this old formula is inaccurate. Young dogs develop fast early on and are much older than we think. Medium dogs age faster than small, and large breeds age faster than medium. Ageing starts accelerating for bigger dogs at about six.

Scientists have developed a more accurate formula to calculate a dog’s age based on chemical changes in their DNA. The American Veterinary Medical Association breaks it down to this:
- 15 human years = the first year of a medium-sized dog
- Nine human years = the second year. 

After the second year, each year = five human years. So, at two, a dog would be equal to 24 human years, adding five for each additional year. The 10-year-old medium dog, by the new calculation, is 64 years old, not 70.

Small dogs are considered senior when they reach twelve, medium size about ten and large dogs around eight. At these ages, our doggy companions start to slow down and show signs and symptoms of ageing, such as greying, arthritis, loss of vision and hearing and possible behavioural changes, basically the same as humans.

Pam Brandis, 
 Dip. Canine Prac.