I am looking to buy a puppy right for me.?

I live on a farm with two horses alongside a small farm road, and my mother and I have decided we want to get a dog. We want to get a puppy of some sort so we can train it and raise it, but we aren't sure what type we want. We are looking for something no smaller than a small Jack Russell, and no bigger than an large Australian Shepherd that can coexist with cats and horses, be an indoor-outdoor dog, is attentive, smart and loyal. If anyone has any breed suggestions or tips, much appreciated. thanks : )