We all know that dogs are covered with fur, which means that their sweating mechanism is different than humans. They pant to cool themselves off as their form of "sweating." Dogs also pant when they get excited (and some may also pee!). Why is that?
Dogs pant to cool themselves
Humans are among the few mammals that sweat—in other words, we secrete beads of water on the surface of our skin, which evaporates to keep us cool. Science Friday explains that dogs and cats sweat too, it just doesn't work to keep the cool the way it does for us. Dogs and cats sweat through the pads of their paws, which does more to provide traction or friction when they are walking or running across surfaces.
The AKC explains that when dogs pant to cool, they hang their tongues out of their mouths and evaporate moisture from their tongues, nasal passages, and the lining of their lungs. This temperature regulation releases body heat and cools them off. Another cooling mechanism is called vasodilation. This means "blood vessels" expanding, especially in their ears and face. When the blood vessels expand, they release heat by carrying blood closer to the surface of the skin, which helps regulate an animal's internal body temperature.
Interpreting dog body language
Panting is one of a dog's means of communication through body language. Hills Pet explains that quiet panting is very much like light breathing. A calm dog may do this and you may not even notice. Dogs pant slightly when they are happy or energetic. For instance, if your dog knows the sound of you picking up the leash or you ask if they want to "go for a walk?" many dogs will automatically start to breathe a little heavier with their tongue out to show their enthusiasm.
Dogs also pant when they are excited, which can be both positive (going for a walk!) or negative (they are nervous or frightened). Purina says this form of body language is something important to look out for. When you see your dog not panting to cool but panting in relation to something unpleasant that is going on in their environment or that they are doing, this is called 'behavioral panting' and it means they are feeling anxious or stressed.
Panting due to stress
Vet Explains Pets describes panting to cool off, panting from happiness, panting from pain, and panting from stress. A dog panting out of happiness will usually have a wagging tail and bright eyes. It's often situation-specific, such as you just got home or they're going for a walk. This is almost like a "smile" in that it is a tell-tale sign they are happy and excited.
You may see this behavior if they are in the car and they don't like car rides. Or if they are waiting in the veterinarian's office. If they are scared of sounds like fireworks or thunder, they may pant when these things are going on around them. You may also see other signs of them being overwhelmed such as repetitive yawning, pacing, whining, licking their lips, shaking, or hiding.
Other causes that may seem innocuous but may trigger anxiety are moving homes from one household to another, having unfamiliar guests or other animals in the home, or noisy appliances such as vacuum cleaners. If you notice signs of stress like this, try to remove your dog from the experience and soothe her as quickly as possible.
When to call your vet
Call your vet if you have concerns about the amount your dog is panting. Hills Pet explains that panting to cool, when the situation calls for it, such as if you've gone on a walk on a hot day, is normal. But excessive panting on a hot day may mean they have overheated and need help. Sometimes, short-faced dogs may pant more, and if your dog is one of those types of dog breeds it's crucial to know what their normal breathing behavior and sounds are.
Vet West Animal Hospital points out that dogs may pant due to illness. They could have something blocking their airway or ingested something that is making them sick. A dog who has gained too much weight may pant uncontrollably as their airways become constricted. Excess panting can also signify a heart problem. https://www.vetwest.com.au/pet-library/why-do-dogs-pant
If you notice panting out of stress happening a lot, or your pet doesn't calm down after a reasonable amount of time after being removed from the upsetting experience, give your vet a call. Your dog may need some help being desensitized to the things that are triggering him. There also may be an unexpected medical condition causing him to be more physically sensitive to things such as noise.
Seeing your dog pant to cool herself off is normal, especially in a context that is familiar: you've just gone on a walk on a hot day, or the air conditioner is broken in your house. Other than that, familiarize yourself with your dog's body language so you can recognize if your dog is panting out of stress or anxiety. Often, an experience such as thunder or fireworks will trigger anxiety in a dog. Or, a vet visit or some other unpleasant experience will stress them out to the point that they pant.
Notice other body language along with that panting, such as whether they are shaking or hiding. It's obvious if your dog is panting due to being happy, because they typically have wagging tails and bright eyes. But panting if they are excited in a stressed out way can look different. Call your vet if the panting seems excessive to you, doesn't go away after a reasonable amount of time, or otherwise doesn't seem normal to you for your dog.