I'm so very sorry Alicia that you're having to deal with this, & I'm especially sorry for your little mares. I hope the pinto will recover. It is such a shame that she's been so badly injured, & my condolences to you on the loss of the palomino.
I also hope the dogs can be found & disposed of. Here we do have a law that allows us to dispatch any dog that is harassing livestock, and believe me, over the years my neighbors have learned that I mean business when it comes to keeping their dogs away from our horses. I tell them in no uncertain terms what will happen to their dogs & how much it will cost them if their dogs do any damage here. We haven't had a dog problem in a long time, & I hope that continues.
Years ago we kept our Morgans at my mom's uncle's place on the edge of a small town. At one point there was a dog problem in that town, & the one evening some dogs put one of our horses over the fence. We didn't see it but he must have tried to jump, hit the wire & flipped himself. He landed in the garden outside the fence, & sure did leave a crater where he landed on his side/back. Mom's uncle scared the dogs off & the horse was okay except for a bit of stiffness the next day. I went snarling to the mayor's office & suggested his council needed to do something about this pack of dogs. There was no animal control officer at that time, and the mayor just kind of muttered & shuffled his feet & said there wasn't anything he could do about the problem. Ha. It wasn't too much later that this mayor was out for a walk one evening--he was just walking around his neighborhood in town--& he was confronted by a couple of snarling dogs. It was amazing how quickly he took steps to do something about the dog problem in that town!