Why dog trembling? common dog shaking , It is definitely reason for concern when you see your dog shaking and trembling. however, it can be difficult to identify the cause. let's look at the most common. Why dog lethargic cold shivering - questions, Why is my dog lethargic cold and shivering why is my dog lethargic cold and shivering out of nowhere i don't know if he ate anything i'm just so worried i just. Tremors/shaking dogs - page 1 - petplace., Tremors are rhythmic, to and fro involuntary movements that persist through the waking state. true tremors stop during sleep. there are a variety of causes of tremors.