Yawning has perplexed scientists and researchers for decades. But humans aren’t the only species subject to yawning. Dogs (and rats and parakeets) have also been known to unwillingly open their mouths, inhaling in a gesture of exhaustion. But why do dogs yawn and what does yawning really mean in dogs? Is it truly about tiredness, sending oxygen to the brain … or is it something more complex?

“Dogs, just like people, will yawn when they are tired,” explains Sara Ochoa, DVM, of DogLab. But is that really all there is to the phenomenon of dog yawning?

Why do dogs yawn when they’re tired?

Why do dogs yawn when they’re tired? And when they don’t like something? Photography by Sergey Gerashchenko / Shutterstock.

Why do dogs yawn when they’re tired? As Dr. Ochoa explains, dogs yawn when they are tired the same way that humans do. According to WebMD, yawning stretches the jaw, therefore increasing blood flow in the neck, face and head. The intake of breath is deeper than “normal” breathing, which causes a downward flow of the spinal fluid and blood from the brain. The cooler air that is inhaled during yawning enters the mouth, cooling the spinal fluid and blood.

Scientists speculate that the reasoning for this seemingly involuntary intake of cool air might be to cool down blood in the brain that’s too hot. Those fluids trickle down, bringing cooler blood from the lungs to the extremities. So, more than yawning being about exhaustion, it might very well may be about body temperature. Of course, yawning is also a part of fatigue.

“[In dogs], this is them stretching their facial muscles and trying to keep themselves awake,” Dr. Ochoa says.

Why do dogs yawn when they don’t like something?

It’s a less common question … but why do dogs yawn when they’re not pleased? Dog yawning happens often during training or traveling or sometimes even on a walk.

According to Dr. Ochoa, it’s no coincidence. Dogs tend to yawn when they’re less-than-thrilled about what you’re asking of them.

“This is them showing that they do not like something. They may be more stressed [in a particular situation],” Dr. Ochoa adds.

As you can imagine, that often makes for a lot of yawning during training class.

“If a dog is yawning in training class, he is either tired or bored,” Dr. Ochoa says. “It can be a good sign or a bad sign.”

Why else do dogs yawn?

Other reasons dogs can yawn might be stress or anxiety. In situations like traveling or even in obedience class, dogs might experience levels of stress or anxiousness. Another situation in which dogs commonly yawn? At the vet.

“Your dog may be stressed or nervous. We will see dogs who come into the veterinary office for exams that will yawn,” Dr. Ochoa explains.

How do you figure out the answer to, “Why do dogs yawn?”

Of course, differentiating which yawn is which is the hard part.

“If your dog is tired, that is the goal of the training class,” Dr. Ochoa says. “You know that your dog may not want to do any more training. If your dog is bored at training, you may need to change your training to something more difficult.”

Alternatively, a tired dog might indicate a dog that listens more readily than a highly-energized one. (They say to bring your pup to the dog park before training class for a reason, right?!)

How can pet parents stop dog yawning?

Yawning in dogs is as much an enigma as it is in humans. While yawning is common in most vertebraed species, we can’t be entirely sure of why either we or animals yawn. There are indications, of course — exhaustion, a need for cooler blood and fluid in the brain, not liking something or boredom — but until more is known about yawning in all species, we pretty much have to take it as it comes.

For both humans and dogs, that means an inability to stop yawns.

“Yawning cannot be stopped or prevented just like in people,” Dr. Ochoa concludes. “If you are tired, you cannot help but yawn.”

Same goes for Fido!

Thumbnail: Photography © Przemysław Iciak | iStock / Getty Images Plus.

About the author

Stephanie Osmanski is a freelance writer and social media consultant who specializes in health and wellness content. Her words have appeared in Seventeen, Whole Dog Journal, Parents Magazine and more. She is currently pursuing an MFA in Creative Writing at Stony Brook Southampton and writing a memoir. She lives in New York with her Pomsky, Koda, who is an emotional support animal training to be a certified therapy dog.

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While it’s relatively rare, Addison’s Disease in dogs is a condition with symptoms that are common in many different ailments, so it’s often difficult to detect … and sometimes diagnosis is only made through a process of elimination for other diseases.

“There’s not one single set of symptoms that defines Addison’s disease, and when it’s taught in veterinary school, it’s often called the ‘Great Masquerader’ because it can look like almost any other disease,” explains Dr. Gary Richter, veterinarian and author of The Ultimate Pet Health Guide.

What is Addison’s Disease in dogs?

Holding hands with a sick or injured dog. Photography ©sanjagrujic | Getty Images.

The common name for hypoadrenocorticism, or adrenal insufficiency, Addison’s disease is caused by a below average production of hormones like cortisol by the adrenal glands, which are small glands located near the kidneys. Adrenal hormones are crucial in controlling the balance of salt, sugar and water throughout the body. “Cortisol is a very important hormone produced by the body; without cortisol, if you woke up in the morning, got out of bed and stood up, you’d immediately pass out because your blood wouldn’t reach your brain and gravity would just take over,” explains Dr. Stephen Katz, veterinarian and founder of the Bronx Veterinary Center in New York. The opposite condition of Addison’s disease is Cushing’s disease, which develops when a dog’s body overproduces cortisol. Cushing’s disease is much more common.

There are also three different types of Addison’s disease: primary, secondary and atypical. Both primary and atypical Addison’s are usually caused by immune-mediated damage to the glands, while secondary Addison’s occurs when the pituitary gland fails to stimulate the adrenals with adrenocorticotropic hormone (ACTH). The disease is often misdiagnosed because its symptoms mimic many other conditions, and the dog may appear otherwise completely healthy.

Addison’s disease in dogs — what dogs are at risk?

While it can affect any dog, Addison’s disease in dogs tends to present itself most commonly in breeds such as Standard Poodles, West Highland White Terriers, Great Danes, Bearded Collies, Portuguese Water Dogs and Doberman Pinschers, Dr. Katz notes. It also tends to impact younger to middle-aged dogs as opposed to older or senior dogs.

It’s also generally understood that the disease isn’t something that can be prevented. “As I understand it, it’s a genetic roll of the dice; it’s the kind of disease that’s predetermined the moment fertilization happens,” Dr. Richter explains. However, he notes that in some cases it’s inadvertently caused when attempting to treat Cushing’s disease — although that’s rare.

Symptoms of Addison’s disease in dogs

According to Dr. Richter, a pet owner may notice that their dog becomes lethargic, starts having gastrointestinal issues like severe diarrhea, or they can even collapse. There’s also something known as an Addisonian Crisis, which occurs when a dog goes into sudden shock due to a circulatory collapse, and can be life-threatening. Of course, any of these symptoms warrant an immediate visit to your dog’s veterinarian.

“Essentially, Addison’s disease is a condition where the dog’s adrenal glands aren’t producing enough cortisone … and a certain amount of cortisone is necessary for these different biological processes,” he adds. “So if a dog is under-producing cortisone, or any other hormones produced by the adrenal gland, it can cause a whole host of physiological problems — and some of them can be life-threatening.”

Diagnosing and treating Addison’s disease in dogs

Since it’s not easily detected by symptoms alone, Addison’s disease in dogs is usually diagnosed with a specific blood test. However, Dr. Katz notes that one of the most notable indicators your pet’s veterinarian might be able to detect via x-ray is a small heart, which is considered to be one of the hallmarks of the disease.

A dog’s treatment will vary based upon which form of Addison’s disease is diagnosed. For most dogs, it will mean taking medication such as corticosteroids, with Prednisone being among the most commonly prescribed, Dr. Katz says. Depending on the nature and severity of the disease, some dogs may need to receive an injectable medication on a monthly basis, while others will require oral medications. The good news is that the disease is treatable and easy to manage once properly diagnosed. “The prognosis is very good once Addison’s is diagnosed,” he confirms. “However, it is a lifelong problem that will require lifelong treatment.”

Thumbnail: ©Monica Click | iStock / Getty Images Plus

About the author

Jennifer Lesser is a New Jersey-based freelance writer. A marathoner, triathlete, and Taekwondo black belt, she specializes in health and wellness — for people and canines — and has written for magazines and websites including Whole Dog Journal, Health, The Spruce Pets, Weight Watchers and Animal Sheltering. She is the proud pet parent of a rescued Cocker Spaniel/Shih Tzu mix named Miles, who has become her favorite running partner. Visit her online at jenniferlesser.com.

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