There’s life in the old dog yet
WORKING out a dog’s age used to be simple and inaccurate. Multiply it by seven and you learn how old it is in human years. But a US study has thrown this method on the bone heap and produced a new way of assessing the age of Man’s Best Friend. Better still for pooches and owners alike, it takes years off the age of older dogs. Environment Editor JOHN INGHAM reports
MY 12-YEAR-OLD black Labrador Inca got some good news yesterday – she’s younger than we thought.
Once thought of as “84”, she has now been born again after shedding 14 years to become a youthful “70”.
An American team says traditional calculations of dogs’ ages are wide of the mark. Instead, it has found a more accurate method by analysing chemical changes in a dog’s body.
Professor Trey Ideker, of the University of California San Diego School of Medicine, said this “epigenetic clock”, based on the rate chemicals are added to genes, is as good a clue to age as the wrinkles in a human’s face.
The problem with the traditional formula is that initially dogs mature faster than humans, but as they get older the rate of ageing slows.
Writing in Cell Systems, the researchers explained: “The comparison is not a 1:7 ratio over time.
“When dogs are young they age rapidly compared to humans. A oneyear-old dog is similar to a 30-yearold human. A four-year-old is similar to a 52-year-old human. Then by seven years old, dog ageing slows.”
It means that a two-year-old dog is not like a 14-year-old teenager but actually middle-aged and closer to a 40-year-old. Prof Ideker said: “This makes sense when you think about it – after all, a nine-month-old dog can have puppies so we already knew the 1:7 ratio wasn’t accurate.”
He worked with Dr Tina Wang and experts on dog genetics, analysing 105 blood samples from Labrador retrievers. He admitted he now looks at dogs in a different light.
Arthritis
He said: “I have a six-year-old dog – she still runs with me, but I’m now realising she’s not as ‘young’ as I thought she was.”
But as for Inca, she thoroughly approves of this new method. She may have a bit of arthritis, but she is always up for walkies.And I’d like to see a 70-year-old human, never mind an 84-year-old, chase a squirrel as quickly as she does.
She certainly had a new lease of life after being told that the kennel in the sky may be a bit further off.
And no matter how old she gets, Inca will always seem like a puppy to me.