originally published March 16, 2013
Regular readers of this site – both the actual ones and the ones I make up when I tell my mother that “millions” of people read my stuff every day – know that I love dogs. I have four of my own – four bulldogs, each with their own distinctive foul odor, their own slobber patterns and mucous-expulsion habits, and naturally their own tub of quirks. Two of them turn five next month, while the elder pair will be creeping in on nine and ten this summer. This brings to mind the default math most people tend to use to calculate a dog’s year vs. a human year, often a 1:7 ratio.
But I’ve got the monstrous power of the internet at my fingertips – surely this myth can be checked, right? Of course it can – I didn’t write 135 words of an introduction just to land on “dunno” and maybe write another article about bacon.
Awesome as that might be.
But no, the science of aging in dogs is actually more interesting than a simplistic equation. Use this to drop on your dog-owning friends when they try to drop the old “times-seven” crap on you.
The idea of ‘dog years’ gets tossed around in two ways. Some use it to refer to the equivalent portion of a dog’s life, so that a 6-year-old dog would be 6 human years or 40-50 dog years, depending on the breed. Others consider the calendar year to be the dog year, so that a 6-year-old dog would be 6 dog years and 40-50 human years old. Both are opposite from one another, yet both can be seen as correct. You probably won’t find that crazy shit anywhere else in science.
Having tossed out the 1:7 ratio – which I’ve also heard as 1:6 because supposedly we’re keeping dogs alive longer than we used to – the next best shortcut is to count the first two years as 10.5 dog years, landing your dog at twenty-one after two calendar years have gone by. This is vaguely accurate. After one year, a dog has roughly reached its full size, and physiologically it is sexually mature. That said, it still needs to fill out its frame, and it may still have an air of egregious enthusiasm and stupidity – about the equivalent of a 12-15-year-old human.
After two years, a dog is about as grown up as it’s going to be. If you own a mastiff, you can probably stop moving from home to bigger home now. Your yippy little terrier’s voice isn’t going to drop into a soothing baritone. Your dog is effectively 18-25 years old, depending on the breed.
After two years, some use the every-year-is-four-dog-years math, so a nine-year old dog would be 49 – 21 years for the first two, then 4 years for the last seven (21 + 28 = 49). I heard about this one a few years ago, and thought I was pretty damn clever for adopting it. Except that it’s totally wrong. Rufus, my nine-year-old, is not 49. That old bastard should be moving to Florida, mini-golfing in flowery polyester shirts and getting in cheap to the movies. Aging varies by breed, so the easy math just won’t apply.
Adult emotional maturity, which humans tend to hit somewhere in the neighborhood of forty years old (or, for those of us who are truly fortunate, not at all), creeps up on dogs around three or four years old. That doesn’t mean you can’t still teach an older dog new tricks – Cesar Milan has effectively put an end to that myth’s relevance – but by then the dog should have lost its “puppy brains”, and he or she is probably about as level-headed as he or she will ever be. If your dog is still fuelled by a manic type of idiocy (and believe me, I feel your pain), then you’re probably not going to see a lot of improvement. Maybe you should have bought a goldfish instead.
Geriatric age, which can be put off in humans with a hearty dose of plastic surgery and carefully thought-out life decisions (I’m saving my alcohol and cocaine binge years until I’m 60), is a little more identifiable in dogs. Small breed dogs, like terriers, Chihuahuas, and those little asshole dogs you just want to punt, they tend to display geriatric qualities around 11 years of age. Medium-breed dogs appear to reach old age at about 10, large breed dogs at 8, and giant dog-horse beasts like Great Danes get old at 7 years.
As for how long you’ve got before doggy heaven comes a-callin’ (sorry, there was no delicate, yet flavorful way to say that), you can actually look that up here. That’s the Dog Longevity website, created by one doctor and culled from several surveys in the US, Canada, Great Britain and Denmark. Some of the sample sizes are a little low, so don’t get freaked out by these numbers.
Naturally I skipped to bulldogs, and was slightly disconcerted to see average lifespans of 4.6 to 6.7 years. The average I’d always heard was about 8-12 years. The variance between breeds really throws a spiky pickle into the entire concept of simple math to determine dog years. You can break it down by size and get a fairly decent approximate guess, but there are a lot of other mitigating factors in the mix. I prefer this site from the folks at Pedigree, which lets you calculate the human equivalent of your dog’s age, specifically by breed. My younger puppies are turning 40; Rufus is turning 65. I can live with that.
The oldest living dogs according to the official record were Australian Cattle Dogs. Bluey, who passed away in 1939, allegedly made it 29 years, six months and twelve days. This is unverified of course, as is the other Aussie dog of note, Chilla, who apparently lived to 32 years, 12 days. The average lifespan for a dog is about 13.3 years. And of course there are a few things you can do to influence whether or not your pooch breaks the average.
First, feed your dog right. One bull terrier cross made it to 27 on a diet of kangaroo and emu meat. Spay or neuter your dog – one study found that neutered female dogs live the longest. Also, don’t take up fire-juggling as a hobby or move into a cramped space under a dark bridge in a busy, traffic-heavy neighborhood. But those are kind of obvious.
No one wants to think about their dogs getting old (unless they really don’t like their dogs, I guess), but it’s a fact of life. You acquired a pet that you knew you’d probably outlive. It’s best to be realistic about it, and stop trying to apply a simple formula to figure out when they get older than you. Stop trying to be clever, and just rely on the internet. Always a good strategy.