I understand the urge! But b***h is used for dogs because that's the technical term for a female dog--just like an "ewe" is a female sheep, or a "hen" is a female chicken. So calling your dames "b***hes" would be nonsense in a breeding context--might as well call thems "cows", and the boys "bulls". (We are all going to end up with 30 billion new infractions as a result of this thread, aren't we?)

Personally, I reserve the term for when I'm feeling friendly towards my female snakes. Urban dictionary says it's a perfectly legit substitution in the phrase: "What's up, girl?"