As a practicing veterinarian of over twenty years, I’ve been nagged by an obvious and seemingly uanswerable question: why do small dogs live longer than large dogs? For years it’s been widely accepted and understood in the pet world that tiny teacup poodles will live ten or more years longer than a Great Dane. They’re both dogs, share the same basic DNA, eat the same types of foods, and live in similar homes. Yet one breed lives up to three times longer. Why? New research sheds some light on this issue.
In the April issue of the scientific journal “The American Naturalist,” biologists at Germany’s University of Göttingen explored the relationship between size of dog breeds and life expectancy. Researchers analyzed data on over 56,000 dogs representing 74 breeds that visited North American veterinary teaching hospitals. The scientists found that larger dogs appeared to age at a faster rate than smaller dogs. Interestingly, the research concluded that every increase in 4.4 pounds (2 kg) reduces life expectancy by approximately one month.
Okay, so my observations on small dogs living longer than big dogs were correct. But why?