Aging and human health are inextricably linked. As we get older, many diseases become more common. In developed nations, age is the most important risk factor for every major cause of death. But most of what we know about the biology of aging comes from studies of yeast, worms, fruit flies, and laboratory mice. The lives of these organisms unfold in days, weeks, or months in the carefully controlled environments of labs. While we certainly have discovered major genetic pathways and important environmental factors that impact the aging process through the study of these organisms, they make an imperfect comparison to dogs and people, whose lives are rich and diverse.
To advance the study of aging, we want to learn more about the ways that genetic background and life experiences interact to shape an individual’s life course. Companion dogs present a fantastic opportunity to help us understand the aging process.
Dog breeds vary tremendously in size and shape from a four-pound Chihuahua to a 150-pound Great Dane. They vary in behavior from lap dogs to hunting dogs to herding dogs, which exposes them to diverse life experiences. Dogs vary in life expectancy with the largest breeds living fewer than ten years on average, while small breeds live comfortably into their teens. Dogs acquire similar diseases as humans over their lifetimes, and for many of these diseases, age-related risk is remarkably similar between dogs and humans.
Companion dogs share the daily environment of their owners, including variation in climate, toxin exposure, infectious disease exposure, mealtimes, and exercise schedule. Dogs acquire diseases in this natural and diverse environment and are treated as individuals over long periods of time. Dogs have a sophisticated health care system, including lifelong relationships with veterinary general practitioners, and have access to 40 different veterinary specialists. In fact, no other species allows us to study the impact of environment and lifestyle on health in all its detail and complexity.
Dogs have long provided humanity with gifts of guarding, herding, hunting, entertainment, and devoted companionship. They make our lives better. As we deepen our understanding of the factors that promote healthy canine longevity, we hope to make their lives better too. In doing so, not only we will be able to translate our discoveries to human aging research, but also we will get to enjoy more of the precious company of dogs!
Kate E. Creevy, DVM, MS, DACVIM
Chief Veterinary Officer