How much time can I expect to have with my Dog? 

Our dogs are family. We hope to spend many happy years with our best furry friends…even though we know parting will be inevitable. That parting will come much sooner for some than for others due to differences in lifespans. How much time can we expect to have with our dogs before they cross the rainbow bridge?  

A lot depends on the breed of dog. The sad fact is that a dog’s lifespan can generally be gauged by its size. Larger breeds have shorter life spans than smaller breeds.   

Size doesn’t relate to lifespan for all species. Naturally very large mammals, such as the elephant and blue whale, have lifespans similar to humans. Their bodies age at a slower rate than smaller mammals, so their bodies last longer. 

So…why does a large dog age more quickly? 

Researchers recently discovered that large breeds have shorter lifespans because they age at an accelerated rate. For example, a Great Dane’s size increases 10x in the first year. Results of a study by Dr. Cornelia Kraus suggest that for every increase of 4.4 pounds of body weight, a dog’s lifespan decreases by one month. 

Our larger pets have shorter lifespans because their bodies mature then wear out faster. They’re also more prone to health issues which can lead to shorter lives.  

Researchers are not yet quite sure why larger dogs age at an accelerated rate. Some think the larger dog’s aging is the result of higher concentrations of growth hormone, or accelerated growth cones with increased radical activity. 

What Are the Life Expectancies of The Large Dogs?  

Large Breeds – some of the largest breeds are the Great Dane, St. Bernard, Bull Mastiff, and Rottweiler. They’re expected to live 8-10 years. 

Medium-size Breeds – this includes the Labrador and Golden Retriever, Bloodhound, German Shepherd, and the French bulldog. They live approximately 10-12 years. 

How Long Do Small Dogs Live? 

  • Small breeds, such as the Pug, Boston Terrier, Whippet, Border Collie, and Beagle, aren’t the smallest of the small dogs. They do have longer life spans at 12-15 years. 

  • Some of the smallest of the small breeds are the Shih Tzu, Lhasa Apso, Cockapoo, Toy Poodle, and Chihuahua. They live to the ripe old age of 15-17.

Do Any Dogs Live Longer Than 17 Years? 

There are dogs on record that have lived much longer than the average age of their breed. For instance, a Beagle named Butch lived 27 years, passing in 2009. 

One of longest living dogs on record is Bluey, an Australian Cattle Dog, that lived 29 years and 5 months. Then there’s Maggie, an Australian Kelpie, that lived 30 years. Maybe it was the clean air because they both lived on farms in Australia. 

When Is My Dog Considered a Senior? 

Large dogs are considered seniors at age 7, medium-sized dogs at about age 9, and small dogs at around age 11. At these ages, dogs should switch to senior wellness care and more frequent checkups. This helps to catch any problems early that could reduce their lifespans. 

What is the Lifespan for Other Pets? 


Cats are the 2nd most popular pet in America. Those that live in the wild have a lifespan of 2-16 years while house cats, living safer lives, have a lifespan of 13-17 years. It’s not uncommon for a housecat to live to 20 years. The oldest cat on record was Crème Puff, who lived in Austin, TX. for 38 years and 3 days.


The third hottest pet in the States is the Ferret. They generally live 6-10 years in the US, and 15 years in Europe due to genetics, diet and exercise.   

Pets from The Rodent Family… 

Guinea Pigs and Hedgehogs live approximately 4-8 years. Their small cousins, Hamsters, Gerbils, and Mice, live only 2-3 years. 

How About Fish and Birds? 

Many people have aquariums with a variety of fish. Fish have an average lifespan across types of 1-10 years. Goldfish, though, can live 25 years if properly cared for. 

A parakeet can live approximately 15 years, while the large parrot lives about 75 years. 

Lizards, Spiders, and Snakes Are Pets Too!

Lizards, such as the Bearded Dragon, live 8-15 years. Female Geckos average 6-10 while their male counterparts live 10-20 years. 

On the flip side of gender disparity, male Tarantulas live up to 12 years, while the female can live up to 36 years.  

The Ball Python and the Boa Constrictor live 20-30 years, though one Python on record lived to be 48.  

Now you have the run-down on pet lifespans so choose carefully. Be responsible and think carefully when choosing a pet. Prepare to take care of your pet for its life time. 

For all of your pet care needs, and at whatever life stage your pet is in, Union Lake Veterinary Hospital is here for you.