Why Does My Dog Shake His Toy. These indicators may be linked to aggression and may require professional help to break. If you see your dog pick up a toy in his mouth, clamp his teeth shut then shake the toy violently, this is an instinctive behavior used to kill or maim a prey animal.

This is most common in dogs left alone for long periods of time or those with severe separation anxiety, according to the aspca. It might just be that your dog is trying to get you to open up to them and have a fun time. That intense shaking back and forth of the head snaps the neck of the.