"She was a breeding dog in a puppy mill, and so she came to us after being kept in a cage her whole life," said Border Tails founder Harleigh Garcia.

After being rescued from a puppy mill, Bertha spent nine months being frequently overlooked because she is a large, senior dog.

If you're a fan of gigantic dogs who are fiercely loyal, intelligent, agile and also capable of taking down bears and wolves ...