If you are anything like me, the “polar vortex” experience this winter left you cuddled up with your four legged family members—maybe even under an extra blanket (or two!). These extreme temperatures had me shivering, which got me thinking about shivering in our pets.
I was mainly thinking about shivering in dogs, as cats don’t seem to experience shivering or trembling as often as dogs, and the more I thought about it, the more I wanted to share my thoughts with our blog readers!
There are so many reasons for dogs to shiver or tremble. The most obvious reason for shivering is cold. Dogs have fur to keep them insulated, so it’s not that common for them to shiver from cold when they’re indoors, but certainly small and toy breeds with thin coats are more susceptible to cold, even when curled up on the couch. Even large breed dogs with thick coats can get super cold when outdoors in cold weather, especially if their coats get wet.
Fear and anxiety as a cause for trembling was second on my list. A great example is a dog who has a storm phobia—when a storm approaches, they can often be found huddled in a safe spot, trembling with fear. Other highly anxious dogs can tremble for just about any reason. Dogs who have “trained” their owners well know that their fearful trembling results in a lot of hugs and kisses, so even if there is nothing for them to fear, they’ll shiver just to garner some attention from you. The best way to avoid this habit is to do your very best to ignore this type of “learned response” behavior.
Have you ever met a dog who was so excitable that they seemed to simply vibrate with energy? In my line of work, I see a lot of those. Some dogs shiver out of pure excitement, trembling with anticipation of the fun that lies ahead. I think we should all take a cue from these dogs, who enjoy life to its fullest every day!
On the other end of the spectrum lies our geriatric friends, who, though they may still get excited, don’t really show it as enthusiastically. Senior dogs can have a tremor, especially in their hind limbs, for no particular reason. We often see these kinds of tremors, which are so aptly named “old dog tremors” in dog at rest, and we don’t particularly worry about them. If tremors don’t interfere with the quality of life these old dogs, we just accept them as part of getting older.
Pain and muscle weakness are two other potential causes for trembling muscles in our pets. If you’ve ever tried to do one last lift of your hand weights after a grueling workout, you know how weakness can cause tremors. Pets who suffer from arthritic pain may tremble because of pain or weakness, or a combination of both.
Finally, there are a slew of medical conditions that can cause trembling. While the trembling we talked about above is for relatively benign reasons (with the exception of extreme cold, which could potentially lead to hypothermia or frostbite), some medical conditions that cause trembling are more sinister.
Hypoglycemia (low blood sugar): very young puppies and toy breeds are susceptible to low blood sugar
Addison’s disease: electrolyte disturbances seen in this condition are responsible for trembling in some dogs
Cerebellar disease: lesions in the cerebellum can cause intention tremors (similar to those seen in human patients with Parkinson’s disease)
Seizures: some trembling is due to small focal seizures
Most of the time, there’s no reason to worry about a healthy dog who has a tremor now and again. But if you pet’s shaking is rattling your nerves, don’t hesitate to bring it up with your veterinarian!