A new study suggests that people seeking a long-lived canine companion should look for a small breed with a prominent nose. The study published in the journal Scientific Reports looked at data on almost 600,000 British dogs from more than 150 breeds, reports the New York Times, which has a full list of breeds. Researcher Kirsten McMillan said lifespans between breeds varied "quite spectacularly." There was a full 10 years between the longest and shortest-lived breeds, though the difference between big and small dogs wasn't huge: Small breeds had a average lifespan of 12.7 years, compared to 11.9 years for larger dogs. Female dogs of any breed tended to live slightly longer than males. The overall average life expectancy for dogs was 12.5 years.
The longest-lived breed was the Lancashire Heeler, a small breed of herding dog with a median lifespan of 15.4 years. Close behind was the Tibetan Spaniel, at 15.2 years. The shortest-lived by far was the Caucasian Shepherd, a large dog bred as a livestock guardian, with a median lifespan of 5.4 years. Two mastiffs, the Presaria Canaro (7.7 years) and the Cane Corso (8.1 years) were the only other breeds with median lifespans below 9 years. Flat-faced breeds, which often have breathing difficulties, had shorter lifespans than dogs with long or medium-length noses. The researchers noted that the database only had information on British dogs and gene pools may be very different elsewhere.
The researcher said their findings contradicted previous studies that found "significantly lower life expectancies for purebreds" compared to crossbred dogs. They found that purebred dogs had an average lifespan of 12.7 years compared with 12 years for crossbred dogs. The study, however, put all crossbred dogs, around a third of dogs in the database, into a single category. McMillan, data manager for the Dogs Trust charity, says the findings will help owners and dog welfare groups, among others, make "informed decisions," the Guardian reports. "But more specifically, I think this provides an opportunity for us to improve the lives of our canine companions," she says. "We are identifying groups that desperately need attention, so we can zone in on these populations and work out what the problem is." (More dogs stories.)