Why Does My Dog Shiver When It Sleeps?

You've surely seen your dog moving around in its dreams at some point, moving its legs as if it were running after something, twitching its ears, and even making sounds like whining or barking.

After a brief while, it wakes up as if nothing happened, or keeps sleeping peacefully. What's happening to it? How should we respond? Below, we'll explain it.

Is It Normal for a Dog to Move While Sleeping?

The twitching and other movements a dog can make while asleep are a completely normal, physiological phenomenon. In fact, we can take it as a sign of good health. Because of this, we should never intervene. The explanation lies in the sleep stages.

What Is Dog Sleep Like?

Dogs' sleep cycle, just like humans', is divided into two stages, each with its own characteristics. One is light sleep and the other is deep sleep. Let's look at them in more detail:

• Slow-wave sleep: this is the lighter sleep stage. It's characterized by relaxation of the body, slower breathing, and decreased heart and brain activity.
• Paradoxical sleep: this deep sleep stage includes the REM (Rapid Eye Movement) phase, which lasts only a few minutes. Unlike the previous stage, there's a considerable increase in brain activity. Breathing also speeds up and becomes irregular.

Rapid Eye Movement Sleep

The changes that occur during the REM phase of canine sleep explain why tremors and other movements and sounds can appear during it. We stress again this is a normal, non-pathological process. Let's take a detailed look at the picture to tell it apart from any other situation that could actually be reason for a vet visit:

• Visible twitches or tremors in the ears, tail, legs, snout, or eyes.
• A running motion in the legs, unmistakable, since it truly looks like the dog is running.
• All kinds of vocalizations, such as whining, barking, growling, crying, or howling.
• Changes in breathing, which speeds up as if the dog were actually doing intense physical exercise.

A Dog's Need to Sleep

Not only should we not wake our dog when it's in a "busy" moment of sleep, but we should always respect its rest. At most, if after the tremors and other movements the dog wakes up startled and confused, we can speak to it in a calm, gentle voice, repeating its name to help it orient itself.

Regardless of its age, a dog needs a comfortable place, sheltered from heat, cold, and rain, to rest. Just as with people, sleeping the necessary hours is essential for good psychological development and, generally, good health.

The bed should be clean, placed in a quiet spot in the house, and suited to the dog's size and characteristics. Keep in mind puppies will sleep more hours, as will older dogs. In these dogs, we may notice they sleep more during the day and, in contrast, less at night.

When to See Your Vet

Outside of these sleep periods, if our dog shows tremors anywhere on its body while awake, we need to check with the vet. There are different conditions that can present with tremors as a symptom.

For example, poisoning, joint pain, or neurological complications linked to different diseases. If the tremors occur occasionally, it's a good idea to record the moment the dog has the episode so the vet can see it. This way, we make diagnosis easier.

Finally, just like people, dogs can also shiver when they feel cold. Some breeds are especially sensitive. If this is the case for our dog, we can dress it in dog clothing to take it outside on days with low temperatures, wind, or rain. Of course, at home it will need a warm, comfortable place to rest.

Psychological Tremors in Dogs

Tremors in dogs while awake can also be due to fear. It's usually easy to identify these cases, since it's possible to detect the trigger. For example, if a storm starts and right then the dog starts trembling, or it does so as soon as it enters the vet clinic.

In these situations, we tend to make the mistake of petting the dog in an attempt to comfort it, as we would with a person. But the dog interprets this as us praising it for trembling.

As a result, we unintentionally reinforce the behavior. It's a solvable situation. We can follow a series of general measures and check with a vet specialized in canine behavior or an ethologist for specific guidelines adapted to our dog.

Bibliography Carlson and Giffin. 2002. Manual práctico de veterinaria canina. Madrid. Editorial el Drac.