Calculating Candles on the Cake: New Research on How Our Dogs Age

By Emily Felty

This week we welcome guest blogger Emily Felty who says this about herself:

 

I’m Emily! I’m an East Coast transplant with a West Coast heart and a few furry rescues. I started volunteering with Old Dog Haven for probably a similar reason that brought you to this blog, a love for old dogs. I write thank you notes for donors and spend my free time reading all the dogs’ bios.

 When my chocolate lab, Mollie, turned 2 ½ we threw her a sweet 16 party. There was cake, streamers and a joy ride around the block (don’t worry Mollie wasn’t driving). At just over 2 years old Mollie had reached an important human milestone, but the old rule of “multiply your dog’s age by 7” didn’t make sense when Mollie passed at the utterly average age of 13. Using the rule, that’s a staggering 91 dog years, nearly two decades more than the human average. So does that old rule really help us compare how our dogs age to how we age? Scientists say no.

An article published on the webpage Science summarized a recent study of dog development that gives us a new way to know when our dogs are ready for their permits, to vote, or to register for AARP. The researchers looked at dog DNA, specifically epigenetic markers, or the indicators left behind as genes change and express themselves over a lifetime. These markers are neon road signs of developmental changes and give us the ability to create aging timelines for our dogs (the science works on humans too!). The study’s resulting timelines were genetic evidence of what can be observed in our dogs as they age. Across the 104 Golden Retrievers that were studied, the epigenetic markers showed clear indication of the incredibly fast development dogs go through in the first year, from toothless, shut-eyed puppies to full bodied adults, before tapering off to a near crawl as the dogs continued to get older and older.

The researchers also took the canine timelines and compared them to previously studied human ones, finding that certain genes in dogs age in a similar way to those same genes in humans. Not only is this potentially helpful information on how to solve age related issues, this comparison is what led the researchers to create a new formula for converting to “dog years.” The resulting algorithm is a bit more complicated and may spark teenage calculus fear, but more accurately represents the relationship between dog and human development. It involves taking the natural log of your dog’s age 16ln (dog’s age) + 31, or just follow the link above to the online calculator.

While this study is just a preprint and the official article is currently awaiting peer review, the researchers are already thinking of next steps to applying this method to future research. A larger question is not just how dogs age overall, but why there seems to be such huge differences in how different breeds age. New research could also help determine why certain dogs are more prone to certain age related illnesses. If you’re interested in following the progress of this research and other dog age related studies you can check out the Dog Aging Project (through the University of Washington and Texas A&M).

Comparing our dogs’ ages to our own is a fun way to enrich our dogs’ lives and our relationships with them, but the real benefit of this research is a greater understanding of our dogs as they truly are. The more we know about how they age means the more we know about how to give them the longest and healthiest life possible. So have fun calculating, put those candles on their doggie birthday cake, and continue to enjoy every moment you spend with your dogs.