In the world of dreams the rules of reality do not necessarily apply. Each dream is unique and it's a direct link to the soul and spirit. Psychology provides its own theories on what dreams mean, but so did tradition and the study of dreams for thousands of years before any relevant science had developed.
Dream Meanings - Donkey
If you dream of a donkey biting or kicking you then you will hear nasty things said about those close to you. If you hear a donkey braying, you will hear unpleasant news. If you simply see a donkey from afar, you will have joy at work.