When is a Dog Considered a Senior? Breed, Size, and More

It should be easy to tell when your dog has reached or is close to senior status, right?

If you’ve had your dog since they were a puppy, you probably know their birthday (or at least an estimate of which month and year they were likely born in), which obviously helps a lot with knowing when a dog is considered senior.

Aside from calendar age, there are often physical signs that indicate a dog’s age as well; grey muzzle hairs and overall being less active than before are all part of being an old dog. But your pup’s breed, genetics, environment, diet, activity level, and overall health can also affect their estimated age. In short, the number of factors that go into determining when a dog is considered a senior is more than just a simple one-size fits all calculation of “one dog year equals seven human years” (but we’ll get into that more later on in this article).

If you have a rescue dog where you’re unsure of their breed (or breed mix) and overall medical history, or you just want some ways to confirm your pup’s age, this article goes through the various ways you can answer the question, “when is a dog considered a senior?”

By knowing the signs that your dog is getting a bit long in the tooth, you can better understand their changing health needs.

When Is a Dog Considered Senior?

Have you ever heard a (human) doctor say that you have the fitness level of an 80-year-old or that the wear and tear on your joints is similar to someone in their 60s? 

Vets use similar logic when trying to estimate when a dog is considered a senior. They’ll look at the condition of the dog’s teeth, move their legs to check the wear and tear of their joints, test their reaction time, and check their vision. The sum total of this information gives the vet a roadmap that provides clues as to how long the dog has been around, as well as their general health.

Blood, urine, and even feces tests can give a vet more information about your dog, including their breed type(s), internal organ condition, nutritional status, and digestive health. 

At What Age Is a Dog Considered a Senior?

Dogs age differently depending on their breed, genetics, nutrition, and overall health. Certain breeds of dog age “faster” because of their unique body structures and genetics.

Larger breed dogs tend to have shorter lifespans compared to smaller breeds. Large and giant breed dogs are at a greater risk of developing life-threatening health issues earlier than smaller breeds.

For example, deep-chested, large, and giant-breed dogs are at a greater risk of developing gastric dilation volvulus, an often fatal condition where the stomach fills with gas and then twists upon itself, blocking its entrance and exit. This condition can technically happen to any dog, but large-breed dogs are up to 10 times more likely to get it. 

An interesting article by Inside Science discusses the differences in how dogs age, specifically how a dog’s size relates to aging. In the article, Cornelia Kraus, an evolutionary biologist at the University of Göttingen in Germany, and her team hypothesized that either:

1. Large dogs age faster
2. Large-breed dogs start aging earlier compared to small breeds
3. Large dogs simply have a higher mortality risk compared to smaller breeds because of their increased susceptibility to life-threatening diseases

To test these theories, the researchers analyzed over 50,000 dogs from 74 breeds taken from the Veterinary Medical Database, which compiles pet health data from North American veterinary teaching hospitals.

When the dog breed data from the database was graphed, the “mortality curve” closely matched the faster-aging hypothesis. Other studies on the IGF1 gene, which is a growth hormone that is found in a large number of organisms, including humans, that seems to be associated with age-related diseases like cancer and heart disease, as well as aging rates, have found that small dogs have less of this hormone, and large dogs have more of it. In other words, less IGF1 gene equals a small dog, more IGF1 gene equals a large dog.

The key takeaway is that if a dog gets bigger faster, it affects their potential lifespan with a higher rate of aging and an increased risk for life-threatening age-related diseases.

The American Animal Hospital Association (AAHA) has proposed life stage guidelines for dogs that outline the different life stages of dogs:

When Is a Dog a Senior: How to Calculate Their Age

There’s a popular misconception that one dog year equals seven human years. This calculation is incorrect overall, as there are many more factors that go into determining a dog’s age than a simple calculation. 

But still, comparing a dog’s age to a human helps us understand the differences between how dogs age compared to humans, gives us further insight into basically when our dogs should hit certain age-related milestones, and helps explain age-related conditions. The “one dog year is equal to seven human years” calculation has likely stuck around because it’s easy for the average person to estimate a dog’s age.

Of course, a dog’s actual age can vary widely from dog to dog. But size is one of the largest (pun not intended) factors that affect a dog’s age. 

The American Kennel Club has provided a generalized chart that takes into consideration a dog’s size when determining its age that people can use to estimate the answer to the question, “when is a dog considered a senior?”

Source

Signs of Old Age in Dogs

When a dog starts to get older, they can start exhibiting different physical and mental characteristics that are different from before, indicating that they have become or are becoming seniors. These signs are important to pay attention to because they could mean you must start making small adjustments to your dog’s exercise routine, diet, and more.

Behavioural Signs that Your Dog is Getting Old

Behavioural changes are one of the most common signs of old age in dogs. Sometimes these changes can result from Canine Cognitive Dysfunction Syndrome (CDS) or Canine Dementia. 

Veterinary professionals have established the acronym DISHA to help them classify the different types of behaviours that could be related to cognitive dysfunction in dogs:

• Disorientation (staring blankly at a wall, getting stuck in corners and not being able to figure out where to go, and otherwise seeming like they don’t know their own environment)
• Interactions with owners, other pets, and their environment are altered or “different” than normal, including aggression, increased attention-seeking, decreased social interaction, and irritability.
• Sleep-wake cycle changes, like sleeping during the day and not being able to sleep at night
• House soiling 
• Activity changes, like overall lethargy and decreased interest in activities that once excite them (walks, playing catch, etc.)

In addition to these behavioural changes, other important indicators of senior dog cognitive dysfunction include:

• Anxiety (fear of people, noises, and specific situations that didn’t bother them before, as well as excessive vocalization)
• Learning difficulties or signs of memory loss (can’t perform tricks or respond to commands that they could before, and inability to learn new ones)

But it’s also important to realize that there can be other reasons why your dog is exhibiting the above behaviours besides “just getting old”. Pain from underlying medical conditions and diseases can also cause behavioural changes. While your dog might indeed be getting old for their size and breed, it’s important to seek a veterinarian's opinion to rule out any other explanations for behavioural changes before blaming them on age.

For example, taking longer to rise from lying down or sitting could indicate joint pain. While the joint pain could be because they are getting older, it doesn’t mean that there’s nothing you can do to help your pup. Incorporating joint supplements with glucosamine for dogs, such as TRI-ACTA H.A., is a good idea to help your aging pup’s joints.

TRI-ACTA H.A is recommended for seniors or dogs with ongoing joint problems because of the addition of hyaluronic acid (which is what the H.A. stands for). Aside from containing two types of glucosamine and chondroitin (helps protect and repair cartilage) and Methylsulfonylmethane (MSM, a natural anti-inflammatory), The hyaluronic acid in TRI-ACTA H.A. thickens the synovial fluid in your pup’s joints, allowing for easier and less painful movement. 

TRI-ACTA H.A. for Pets

Our maximum strength formula is optimally designed to accelerate the formation of cartilage, minimize inflammation, expedite the healing process, and improve joint conditions.

Learn More