Bitch fights are serious business. Fights between females are both more likely to escalate and cause serious damage, and have a poorer success rate for rehabilitation. I can't begin to guess what started this, but it's very common for bitches who fought once to do so again.
The first thing I would do in your situation is separate the 'victim' from your other dogs, at least the females, for her own safety. I would also bring her to a vet and get her a full workup - very occasionally you hear about dogs turning on their housemates because they're "off" or ill in some way that the dogs can sense (smell, probably) but isn't bad enough for humans to notice yet.
If she gets a clean bill of health, you need to contact a veterinary behaviorist or a certified behaviorist who uses up-to-date, science-based methods (reward based, no nonsense about being a 'pack leader' and 'dominating' your dogs) and has experience with aggression. The CCPDT or APDT are good places to start. Some behaviorists will even do skype consults, which is obviously not ideal but better than trying to deal with a serious aggression issue alone.
It's entirely possible that you may need to do crate-and-rotate with this dog for the rest of her life to keep her safe, or rehoming her if that will allow her a better quality of life. Behaviorists can do a lot, but as I said, aggression between females is one of the more difficult issues to tackle, even when only two dogs are involved.
The first thing I would do in your situation is separate the 'victim' from your other dogs, at least the females, for her own safety. I would also bring her to a vet and get her a full workup - very occasionally you hear about dogs turning on their housemates because they're "off" or ill in some way that the dogs can sense (smell, probably) but isn't bad enough for humans to notice yet.
If she gets a clean bill of health, you need to contact a veterinary behaviorist or a certified behaviorist who uses up-to-date, science-based methods (reward based, no nonsense about being a 'pack leader' and 'dominating' your dogs) and has experience with aggression. The CCPDT or APDT are good places to start. Some behaviorists will even do skype consults, which is obviously not ideal but better than trying to deal with a serious aggression issue alone.
It's entirely possible that you may need to do crate-and-rotate with this dog for the rest of her life to keep her safe, or rehoming her if that will allow her a better quality of life. Behaviorists can do a lot, but as I said, aggression between females is one of the more difficult issues to tackle, even when only two dogs are involved.