The qualities of dogs are frequently desired and envied by humans. Artists and sculptors frequently try and bring out these aspects of their subjects by strategically placing dogs at the feet of the people they are trying to depict.

If it's a woman who has a dog at her feet, the qualities of the woman are shown to be affection and fidelity. The artist indirectly tries to associate these qualities with women by instigating the feeling in the viewer by depicting the dog.

Men like priests (or the pope) or religious warriors used to have dogs placed at their feet in depictions to symbolize the faithfulness with which they server their master (God).

So we see from this that dogs have always struck a deep note with mankind. Artists, who are among the most sensitive of men have liberally used dogs to more poignantly bring out the characteristics of their subjects.