Can dogs live longer?

WEST LAFAYETTE – Audrey Ruple loves Great Danes so much that, while in the middle of Texas on a family vacation in 2012, she made the decision to get another one.

Audrey Ruple, a veterinary epidemiologist and assistant professor of One Health Epidemiology in Purdue University’s College of Health and Human Sciences, with Bitzer, a Great Dane. Purdue University photo/Rebecca McElhoe

“We were lucky that we had a vehicle large enough to hold an extra passenger,” says Ruple, recalling how Bitzer, a purebred Great Dane that eventually grew to 140 pounds, came to live with her family.

Despite the rocky trip back to Colorado, he became rather mellow and the go-to animal for cuddles and chuckles.

“He was the best dog. He was my heart dog,” Ruple says.

Bitzer recently died after living a large life. He was almost 8 ½ years old.

“He was old for a Great Dane, but much too young for a dog to die,” says Ruple, who is an assistant professor of public health and a veterinary epidemiologist. She researches dog longevity through the Dog Aging Project.

Being a licensed veterinarian who knows the ins and outs of animal health doesn’t make the loss easier.

“The old thought of how ‘the larger the dog, the shorter the life span’ rings true in this case. We are still not sure why that is,” Ruple says. “Dogs break the rule of every other mammal species. Most mammal species, it’s the bigger you are, the longer you live. That’s why we’re doing this research with the Dog Aging Project.”

Bitzer had one serious medical issue: osteosarcoma.

Ruple has worked with numerous scientists, researchers and veterinary oncologists on studying osteosarcoma in dogs, as they are the perfect translational model for osteosarcoma in humans.

“Dogs and humans develop the same type of osteosarcoma. It is the same at the molecular level,” Ruple says. “If we look at an osteosarcoma from a dog, we can’t tell the difference between that and an osteosarcoma from a human.”

Osteosarcoma is the most common bone tumor in dogs but is considered a rare disease in humans. According to the American Cancer Society, there are about 1,000 new human cases diagnosed every year, and half of them are children, teenagers or young adults.

Ruple says osteosarcoma is difficult to study in humans as researchers can’t develop randomized control trials because they don’t have enough people to enroll.

Tyler Trent, a Purdue graduate and superfan who died Jan. 1, 2019, had osteosarcoma. Trent donated his cancer cells to further cancer research.

“The group that osteosarcoma hits most are rapidly growing teenagers. In dog populations, we find osteosarcoma in large breed dogs, which are rapidly growing mammals,” says Ruple, who is an affiliate faculty member of the Purdue University Center for Cancer Research. “We think there is something in the growth rate that triggers the cancer to form. It makes sense that humans and dogs have similar cancers because we share a huge amount of genetic sequence, and cancers arise from our own cells.”

Because of that shared genetic sequence, cancer treatments that are developed and successful in dogs are frequently adapted for use in humans.

The importance of collaboration and community science

When Ruple began her veterinary epidemiological studies, she knew she wanted to explore translational and preventive medicine, cancer outcomes and infection control in dogs and humans. She studied zoonotic diseases – which are illnesses that can be spread between humans and animals.

“My goal has been to look at health and disease of humans and animals, and ask, ‘How do we stop diseases from occurring?’” she says.

She was contacted by Daniel Promislow and Dr. Kate Creevy of the Dog Aging Project, seeking her involvement in the design for the longitudinal study, which eventually was funded by the National Institutes of Health. The project explores biological and environmental determinants of aging in dogs.

“The Dog Aging Project and the epidemiological work I do is about being able to keep people and animals living healthier lives for longer periods of time. That, to me, is really compelling. A lot of diseases we see in dogs are the same ones that happen in our children,” Ruple says. “Sickness for children has long-term impacts. If they have cancer – even if they are cured or treated to remission – those chemotherapeutic agents and surgeries we use to treat them have lifelong impact. They live a life that may be a little less than perfect.”

Currently, the Dog Aging Project has nearly 30,000 dogs – 727 from Indiana – whose owners have completed full enrollment, including completing the questionnaire and uploading complete veterinary medical records.

The top five locations for Indiana-registered participants are Indianapolis (Marion County), Lafayette (Tippecanoe County), Bloomington (Monroe County), Muncie (Delaware County) and Fort Wayne (Allen County). The top five breeds registered from Indiana are golden retriever, Labrador retriever, German shepherd, dachshund and beagle.

Organizers are hoping to get additional dog breeds to make the study more whole:

  • Large breed dogs weighing 70-100 pounds, especially breeds other than Labradors, golden retrievers and German shepherds (the most common breeds in the U.S.).
  • Giant-breed dogs weighing more than 100 pounds, such as Great Danes, wolfhounds, mastiffs.
  • Hound dogs, spaniels, pointers, terriers, bulldogs and pit bulls (purebred and mixed breed).
  • Working dogs, such as herding, K-9, service, agility and mushing dogs.

Organizers also are looking for dogs from rural areas, small towns and large cities. Many people are adopting animals from shelters or getting a puppy during the COVID-19 pandemic, and puppy participants are especially beneficial to the project as researchers could follow the dogs through their entire lives.

Ruple says it is important for a diversity of dog owners to participate in health so researchers and scientists can study health outcomes of underrepresented minority populations.

To participate in the Dog Aging Project, owners nominate a dog (one per household) at After this, they are invited to set up a personal research portal where they answer scientific surveys about their dog and upload veterinary records. 

“What we can learn from dogs is really important,” Ruple says. “They truly are our best friends.”

About Purdue University

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Information: Matthew Oates,,, @mo_oates

Sources: Audrey Ruple,, @audreyruple

Amber Keyser, Dog Aging Project

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