It's kind of fun to project human egoistic foibles onto animals, but the reality is that they do not have ego at all. They are, what is called in Hindu philosophy, pashu - completely bound to, and integrated with, the Self. However, this doesn't mean they don't have personalities. The difference between ego and personality is that the former is illusory while the latter is a real manifestation - a facet - of the singular but multifaceted Self. Ego is not a component of the true personality, it occludes the real personality.