Dog years, cat years
I frequently hear people estimating their dog’s ages in human years using a “times seven” formula, e.g., a three-year-old dog would be said to be equivalent to a 21-year-old human.
The American Kennel Club, a nonprofit organization that regulates the recognition and registration of dog breeds and provides reliable information on canine matters, traces this “times seven” formula to an era when American dogs lived an average of 10 years, which was considered very old and was presumed equivalent to 70 human years.
When I was in veterinary school half a century ago, there was no discussion of geriatrics, not even this times seven formula, but a few years after graduating, I began to hear of a rather complicated formula, where each month of the first two years of a dog’s life was equivalent to one human year, so two dog years would be equivalent to 24 human years; your puppy now a young adult. After that, a dog’s physical development slows down, with each dog year equivalent to four human years.
This new formula made a good math exercise for kids, and also made scientific sense. With nonhuman animals, “childhood” is brief, involving rapid physical development, although, as with humans, socializing skills remain vital. It helps to keep young and old dogs and cats together for the young ones’ “education.”
Veterinary research has also clearly shown that there are differences in canine life expectancy depending on the size of the dog. Larger dog breeds generally have longer lifespans. For example, dachshunds can live an average of 10 to 15 years (I had one that reached the age of 18), while a Great Dane’s average lifespan is eight to 10 years. Mixed breeds, like our aspins (asong Pinoy), are sturdier than purebreds (which tend to suffer from too many diseases produced by inbreeding).
A warning here: class factors enter the picture, too. A dog in the Philippines—purebred or aspin—is considered very old even at the age of five; our dogs often die early (sometimes mercifully) because of neglect, illnesses, and accidents.
And cats? There’s much less information on cat years compared to human years. As with dogs, there were simple formulas; the most often I’d hear was one cat year equals five human years. Again, more scientific calculations have been made, which can get quite complicated. For example, a one-year-old kitten is equivalent to a 15-year-old human teenager. Go figure that out, including the possibilities of pregnancy. Now you can warn your teenagers, “Remember, you’re still a one-year-old kitten as far as science goes. Meow.”
There are practical reasons for all these estimates on age equivalencies. I found on the internet a few charts that are color-coded, showing when our pets are puppies and kittens, adults, seniors, and senior-plus. Hey, maybe we should have a senior-plus discount card for humans and pets.
Our military and police retire their service dogs at the age of eight, based on the old “times seven formula,” meaning at eight, service animals are thought to be about 56 human years, which is the retirement age for the military and police.
Knowing the equivalencies alerts us to the changing needs of our dogs and cats. Puppies and kittens, like human children, are full of energy and curiosity, which means extra vigilance is needed in their care. Adulthood is usually uneventful, but we should not forget annual rounds of vaccinations, and, in many cases, having the dogs and cats altered (sterilized), which lengthens their lives.
Watch out as dogs and cats approach senior citizenship. As with humans, you have to watch their weight (read, more exercise), cut down on their protein, fat, sugar, and salt intake. Dogs and cats also develop dementia and other geriatric diseases. I’m writing this column having lost two elderly dogs (siblings, actually), aged 15, within the last two months. One was blind for four years but did quite well; content to sit quietly out in the garden, enjoying the smell around him. The other, who died just two weeks ago, had dementia and problems of coordination. Both went quietly, with minimal suffering, at home.
When I was in vet school, we had no lectures on geriatric pets, much less on end-of-life issues, and even today, there’s a lack of information on the needs in this area. I thank the Veterinary Practitioners Association of the Philippines (VPAP) for asking me to do a keynote address at their convention, giving me free choice on the topic. The timing was appropriate, a reminder to write more about veterinary issues.
The VPAP topic I chose: the challenges of growing old together, happy, and healthy, with our four-legged friends.
