The dogs that live the longest, by a nose

There are exceptions to these broad trends, and the findings may not apply to dogs outside Britain, where breeding practices – and gene pools – may be different, the researchers noted.

More research will be needed to determine why some breeds have shorter lifespans than others. Some breeds are genetically predisposed to serious health problems, but breed-related differences in behavior, lifestyle, diet, environment or other factors can also play a role in shortening the lives of some dogs, experts say.

“Now that we have identified these populations at risk of premature death, we can start to investigate why that is so,” said Kirsten McMillan, author of the new study and data manager at Dogs Trust, a dog welfare charity in Britain. who led the investigation. “This gives us the opportunity to improve the lives of our dogs.”

The study is based on a database of 584,734 British dogs, which the researchers compiled from breed registries, pet insurance companies, veterinary companies and other sources. This type of data, which can be subject to various biases, is not necessarily representative of the general dog population in Britain, the scientists acknowledged.

But Dr. Audrey Ruple, a veterinary epidemiologist at Virginia Tech who was not involved in the new study, said the researchers' use of so many different data sources was one of the study's strengths. “I think this is a fantastic approach,” she says.

Most dogs were purebred and represented one of 155 breeds; the rest were combined into one crossed category. The researchers categorized each breed's overall body size as small, medium or large and the head shape as flat, moderately proportioned or long.

For all dogs, the average lifespan was 12.5 years, the researchers found, but the average lifespan varied “quite spectacularly” between the breeds, said Dr. McMillan. Lancashire heelers, a breed of small herding dogs, were Methuselah dogs, which lived an average of 15.4 years. The much bigger However, Caucasian Shepherd Dogs had an average lifespan of only 5.4 years.