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If you have had your dog since they were a pup, you probably know how at least roughly old they are, even if you don’t remember to get them a special treat for their birthday each year. But what about when you adopt a dog from a rescue, how do you know how old they are?
There are a variety of characteristics you can refer to to determine the approximate age of a dog. In this article, we’ll take you through some of the most effective ways to tell how old a dog is and some other dog-age related facts.
Bear in mind that determining the age of your dog in this fashion is not an exact science. So, while you might be able to determine approximately what life stage they are in, you probably won’t be able to put an exact number on their age.
How To Calculate Your Dog’s Age In Human Years
We’ve all heard that one dog year is the equivalent of seven human years. While that might roughly align with the general lifespan of dogs compared to humans, it doesn’t really reflect the different life stages that dogs pass through.
In reality, dogs mature more quickly than humans early on. They then tend to stay healthier and happier than most humans until their senior years, when they start to age more quickly again.
Your dog is probably the equivalent of a 15-year-old human by the end of their first year of life and then a 25-year-old human by the end of their second year of life. After that, they probably age the equivalent of about four human years for every year that passes.
However, it is also important to remember that not all dogs age at exactly the same pace. Bigger dogs tend to have shorter lifespans than smaller dogs, so they will start to feel older a bit earlier.
For example, you can expect a German shepherd to live about 10 years, while Labrador retrievers usually live for about 12 years on average. Alternatively, you can expect a smaller dog like a Dachshund to live for maybe 15 years and a tiny Chihuahua to live for up to 20 years.
What Are The Different Canine Life Stages?
More important than being able to determine your dog’s exact age in human years is to understand the different canine life stages, when they happen, and what they mean for the health and care of your dog.
Dogs generally pass through four different life stages. Let’s take a look at each one in a bit more detail.
1. Puppyhood
While your dog will always be your baby, puppyhood is when they are actually an infant dog. This period can last until a dog is just six months old, or it can continue until they are 18 months old, depending on the breed.
When dogs are born, they are pretty helpless. They are deaf, blind, and unable to regulate their own body temperature. This is why they need to stay close to their mother and littermates during these crucial weeks.
At between two and three weeks old, they will start to open their eyes and move around a bit, but not far, and there will be lots of tottering and falling as they learn to walk.
At this point, it is clear that they have a new interest in their surroundings. They will be more responsive to you and more likely to chew on and destroy anything in their path, but they will still continue to stay close to their mother at this time.
The earliest that puppies should be taken away from their mothers is eight weeks, which is roughly when they should be eating on their own and regulating their own body temperature properly.
They will be curious, playful, and above all, interested in exploring and getting into everything. They tend to grow rapidly over the following months, reaching their full size at between 6 and 18 months depending on the breed.
The best time to start formal training is when your dog reaches around 6 months old, especially if you want to teach your dog any specialized skills.
Read more about the ages and growth stages of puppy development.
2. Adolescence
When your dog exits the puppy phase, they will enter the adolescent phase. Depending on the breed, this stage can take place at any age between 6 and 18 months.
You will know your dog has entered this stage once their hormones start to kick in. Female dogs will have their first heat cycle, and male dogs will start to be very interested in other dogs and begin marking their territory with urine.
This energetic and hormonal stage will last until somewhere between 18 and 24 months for smaller dog breeds, and it can last until a dog is as old as 36 months in larger breeds.
Just like with human adolescents, this can be one of the stages when it is very challenging to manage your dog, as their hormones are dragging their attention in many different directions. Firm and clear rules are needed at this time.
3. Adulthood
At some point between 18 months and three years, depending on the breed of your dog, they will mature into an adult. While they are still strong, healthy, and energetic, you will notice that they have more even energy and are better at paying attention upon reaching this stage than they were as a puppy or adolescent.
At this time, you’ll probably find that you can trust your dog to do things that they couldn’t do before, such as join you on the boat or hike in front of you off-leash.
4. Senior Years
Dogs enter their senior years and start to slow down sometime between the ages of 7 and 10 years depending on the breed.
You will notice at this stage that they are a bit less energetic and will sometimes just watch you if you go out with the ball. They will also need more sleep and will be more comfortable with just lazing around the house.
This stage is also when most dogs are likely to start developing health problems, and you should be on the lookout for signs that they are suffering from physical pain or are having difficulty with any of their senses, such as sight and hearing.
You can read about what is involved in caring for a senior Labrador retriever here.
How To Estimate A Dog’s Age
As human beings, we know our bodies tend to show our age and that things such as smile lines and grey hair can help us guess how old someone is. Dogs also have a number of characteristics that change with age and can be used to determine how old they are.
However, it is also important to remember that, just like with humans, an unhealthy lifestyle can cause premature aging. If they’ve had a poor diet and no exercise, your dog may appear older than they are. After six months of careful love and care, you might want to reassess their age.
Below are some features to pay close attention to when estimating your dog’s age.
Teeth
Just like with humans, teeth are one of the key indicators of a dog’s age, especially in the earlier years of life when their tooth profile is changing.
Teeth are most effective as an estimator of age during the first six months of a dog’s life when they are shedding their baby teeth and their adult teeth are coming through. Most dogs have a complete set of adult teeth by the time they are six months old.
After this stage, age becomes harder to determine, but wear and tear can also be a good indicator. In most dogs, tartar will start to form around the molars between the ages of twenty months and two years, while the canines will remain clean.
The buildup will be reasonably light at this age, and by five years it will be significantly more noticeable and will have likely spread to the canines as well.
A dog’s incisors will also start to wear down when they enter middle age. A poor diet can cause this to happen sooner, but slight incisor damage is generally a good sign that they have entered middle age.
Eyes
Looking into a dog’s eyes can also help you determine whether they are still a vibrant young adult or if they are starting to enter their senior years. This is due to a common eye condition known as lenticular sclerosis, which starts to affect many dogs between the ages of six and eight, depending on the size and breed.
During the early stages, the disease takes the form of thin lines across the lens of the eyes. Later, the pupils will start to take on a grey, white, or even bluish tinge. Even if their eyes are quite badly affected, this condition doesn’t tend to affect a dog’s vision adversely until they are very old.
Coat
For humans, skin and hair are some of the clearest signs of aging, and the same is true for dogs.
Puppies tend to have softer coats that feel more luscious under the fingers. This may not be immediately apparent with a rescue dog, since a poor diet will quickly affect their coat. However, after a few months of healthy food and regular grooming, their coat should return to a smoother, healthier state.
Graying around the muzzle, the top of the head, and the eyebrows can be a sign of advanced age, though some breeds start to turn grey younger than others. Red, yellow, and golden dogs often go white on the top of their head and around their muzzle in middle age.
Behavior
As already discussed in our review of the four canine life stages, dogs tend to have different energy levels and behavioral patterns at different points in their lives.
For example, if your dog has low energy levels and is slow to respond to things, they are probably already at the senior stage. Alternatively, if they are humping everything in sight and marking their territory regularly, then they are probably in the adolescent phase.
It can be very difficult to age a dog based on behavior, especially if you didn’t know the dog before. However, if you do your research on the breed, you can get a good idea of typical behavior and make a guess.
FAQs About Determining A Rescue Dog’s Age
How do rescues know how old a dog is?
Rescues will typically use the same indicators we have discussed in this article to determine the age of a dog in addition to any background information they have at their disposal. They also have the benefit of access to qualified vets and plenty of experience working with dogs to help them make an accurate judgment.
Does my rescue dog remember his old life?
While the memories of dogs don’t work in the same way as human memories, it does appear that they are capable of remembering things that have happened to them, even in the distant past. How they relate those memories to the here and now, though, is unclear.
Do shelters make up birthdays?
With the exception of puppies, when a birthday can be guessed with relative accuracy, if shelters give a dog a birthday, it is probably made up. August 1 is known as “Dogust 1” because it is the generic birthday that many shelters and rescues give to their dogs.
The Verdict
Oftentimes, when you adopt a dog from a rescue, it is impossible to know exactly how old the dog is. There are usually no health records, and there are no definitive markers that can tell you with certainty precisely how old a dog is.
If a dog is less than six months old, a vet should be able to tell you their age pretty accurately based on their teeth, but after that, the signs are a lot less clear.
Nevertheless, things like the color and quality of your dog’s coat, the appearance of their eyes, and their behavior, in general, can help you determine what life stage your dog is in, even if you don’t know their exact age.
Do you have experience caring for older dogs adopted from a shelter or rescue?
Share your thoughts with the community in the comments section below.
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