5 min read


Can Dogs Smell Illness in Other Dogs?



5 min read


Can Dogs Smell Illness in Other Dogs?


As humans, when someone we are close to is unwell, we can pick up on this because of the way they act and because they will often tell us how they are feeling. However, when it comes to our pets, it can be difficult for us to determine if and when they are unwell. 

While dogs do show signs of illness, many of these signs are very non-specific – for instance, there are certain signs that could indicate that your dog is ill but the same signs could also indicate that your dog is bored or just out of sorts on that particular day. 


Signs Your Dog Detects Illness in Another Dog

While humans find it difficult to work out whether their pooch may be ill, dogs are far more efficient at identifying ill health in humans. In fact, many dogs are trained to do just that and can sniff out a wide range of health problems ranging from migraines through to cancer. 

Not only are they able to sniff out illness in humans, but they can also do the same when it comes to other dogs, and this is largely due to their incredible sense of smell. When a dog picks up on illness in another dog, this is not because it has been watching how the dog behaves but because it can smell something that enables it to detect illness.

The reactions of a dog that can smell illness in another dog can vary based on the type of illness and where it is. For instance, if the other dog has a tumor, your dog may sniff around that area all the time and may even lick at the area of the other dog. Your dog may follow the ill dog around more than usual and may spend a lot of time staring at it, whining, or head tilting. 

Many dogs will indicate that there is a problem through the use of body language. For example, some dogs may paw tap at the other dog if they detect the signs of illness while others will spend a lot of time sniffing around the area depending on where and what the illness is. 

Licking is a common way for animals such as cats and dogs to display signs of illness – some will lick at the area that is injured and hurt for comfort or even because they are trying to ‘lick away’ the illness. Your dog may also, therefore, lick the other dog in the area that is affected. 

Body Language

Signs your pup has detected illness in another canine include:

  • Staring
  • Whining
  • Paw Raised
  • Licking

Other Signs

<p>Depending on how close your dog is to the other dog, it may even spend more time cuddling up or putting its head on the other dog’s body when they are lying down. These are some of the additional signs your dog may display if it detects illness in another dog:  </p>

  • Sniffing At The Affected Area
  • Putting Its Head On The Other Dog
  • Cuddling Up To The Ill Dog

History of Dogs Being Used to Sniff Out Illness


The canine sense of smell is something that has been studied for many years and the results of these studies have shown us just how effective a dog’s sense of smell actually is. As a result, dogs have been trained to use their ability to sniff things out to get involved in various jobs including becoming official illness dogs that can sniff out cancer, migraines, and other illnesses in humans. 

In the same way, they are able to sniff out illnesses in other dogs and, according to some experts, they are far more efficient at detecting diseases and illnesses in their early stages than much of the high tech equipment used today.

Over the past century, in particular, researchers have discovered just how invaluable a dog’s ability to sniff things out can be. Over more recent years, this is something that has been utilized to help people in various sectors such as law enforcement, the military, and many other sectors. While the use of dogs to detect illness is pretty recent in the grand scheme of things, our pooches have proven themselves to be pretty remarkable when it comes to detecting a wide range of health problems in both humans and in fellow canines. 

Science Behind Dogs Smelling Illness in Other Dogs


When it comes to using their sense of smell to detect problems and issues, some dogs have been specifically trained to do this from a young age. For instance, dogs that can detect cancer in humans have been exposed to blood samples from cancer patients during training, which enables them to familiarize themselves with the smell and detect it.

However, even with dogs that have not been trained, their keen sense of smell means that they are able to pick up on changes and problems in both humans and other animals. They may not have been exposed to the smell before, but to them, it will be something that is different from the norm. 

Taking Note of Your Dog's Behavior


Dogs that are used to detect illnesses in humans go through rigorous training in order to familiarize them with the signs and smells that are associated with that particular illness. Once they are trained, they can then effectively identify the onset of that illness and alert their owners through their behavior, signs, and body language. There are now also institutions and studies that focus on the training of dogs to sniff out and identify diseases such as cancer in other dogs, which could prove invaluable to the veterinary field.

If you have more than one dog, it is well worth looking for certain signs that your dog may display when it is around the ill dog. You may notice your healthy pooch acting unusually around the other dog and displaying some of the signs outlined above. If your healthy dog does this every time it is around the other dog, there may be something afoot and you may want to check the area that your dog keeps paying more attention to on the other pooch. If you are concerned, it is best to contact your vet or make an appointment to get the potentially ill dog checked out just to be on the safe side.

By monitoring any changes in behavior or any signs that your healthy pooch displays around the other dog, you could actually catch a serious condition such as cancer at an early stage, which could make all the difference to your ill dog. If your two dogs are very close, your healthy dog may look very subdued and depressed around your other pet if there is something wrong, so this is something else you should look out for. Even without specialist training, dogs can pick up on unusual smells such as those tied with certain conditions, and they can therefore provide you with an invaluable warning sign. 

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By a Boston Terrier lover Reno Charlton

Published: 05/04/2018, edited: 04/06/2020

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