There are so many wonderful things about having a dog. One of the worst things, though, is knowing that it’s an almost certainty that they will outlive you.

Your dog’s average lifespan depends on myriad factors, but this new research suggests there is one factor that’s more important than all the others.

Dogs live an average of 10-13 years, which is roughly like a human living for 60-74 years of age.

Small dogs with long-noses live the longest (on average), while medium-sized, flat-faced breeds typically live the shortest lives.

The UK recently published a report based on 580,000 dogs from over 150 breeds in the hope of identifying those most at risk of an early death.

They classified the dogs by size (small, medium, large) and head shape (short, medium, or long-nosed), then calculated life expectancy for each combination (sex, size, and head shape).

They found that while small, female, long-nosed dogs had a median lifespan of 13.3 years, but small, female, short-nosed dogs only lived an average of 11.2 years.

The latter also had a 40% increased risk of shorter lives than dogs with medium-length snouts.

The 12 most popular breeds accounted for over 50% of all recorded purebreds in the database. The largest factor in whether or not they lived a longer life seemed to be their snout-length.

Previous research has also suggested that small-nose dogs like French Bulldogs and Pugs live shorter lives because of complications and various common health issues.

The main one being, of course, brachycephalic obstructive airway syndrome (boas).

With symptoms like panting, overheating, exercise intolerance, retching, gastrointestinal signs, and disturbed sleep, the condition is almost always life-threatening.

This is a concern for scientists and dog lovers everywhere, because not only are their lives often marked by suffering, they typically live much shorter ones, too.

It raises ethical questions around the decision to continue breeding dogs likely to suffer (and die) from boas and its symptoms.

Countries like the Netherlands and the UK are considering laws to limit the breeding of these types of dogs, though current Animal Welfare Acts and Statutes don’t address this exact issue.

Any changes made would not affect people who currently own such companion animals in these countries, but people who do own them need to understand that their veterinary bills will likely be much higher than average.

The results of the study should give people that little extra bit of information when it comes to deciding which breed of dog is right for their family.

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