Puppies may seem like they are a never-ending source of energy and trouble, but, they won't be like that forever - in fact, scientists say our furry friends age a lot faster than we used to believe.
Most people have heard the old wisdom that as your dog ages, one dog year is equivalent to seven human years. However, researchers at the University of California, San Diego, School of Medicine, found that dogs age very quickly during the first five years of their lives, then much more slowly later on.
“Puppies age super quickly,” said Trey Ideker, the study’s senior author and a professor of genetics at the University of California, San Diego, School of Medicine. “By the time a dog is a year old, at a molecular level, he’s much more like a 30-year-old human. Retrospectively, we did know these things. It didn’t make any sense that the equivalent to a 7-year-old human would be able to have puppies.”
Researchers examined chemical changes to canine DNA and noticed that dogs, like humans, have chemical markers on their DNA that change with age. The marks, called 'methylation marks,' are like "wrinkles on the genome" that change in predictable ways as humans and dogs age.
“The genome itself doesn’t change with age,” Ideker told NBC News. "What does change is marks on the genes that control a dog or human's growth pattern."
The study, which was published in the journal Cell Systems, examined 104 Labrador retrievers that ranged in age from weeks-old to 16-years-old.
“We are able to quantify this at the molecular level and tell how fast someone is aging, and we can align it across dogs and humans,” Ideker said. “But we don’t know exactly what it all means.”
Researchers were able to come up with a new equation that would help figure out your dogs comparable human age. If you'd like to find out how old your dog is right now, grab a calculator with a natural logarithm "ln" function. Type in your dog's age, then hit the "ln" button. Multiply that result by 16 and add 31 to that.
For example, by the time a dog is 5-years-old, the dog is closer to 57-years-old in human years.
So, maybe the next time you go out with your pup and he's running a little slower than before, you'll know the old pup is a lot older than you previously thought.
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