If the dog's are properly cared for, I don't view it as hoarding. The Queen has six or seven Corgis, though I don't think anyone considers her a hoarder.
When the person can no longer care properly for their pets, yet keeps getting more, then that's when I believe it becomes hoarding.
When the person can no longer care properly for their pets, yet keeps getting more, then that's when I believe it becomes hoarding.