To be fair to yourself and the dog do some research on the different dogs FIRST! Simple things like a Blue Heeler works beside you driving the livestock while a Border Collie works on the opposite side of the livestock bringing them to you can mean the difference between being a happy dog owner and an unhappy dog owner.

I have owned both Border Collies and Red Heeler and they both have their place. The Red Heeler I worked with cattle and is a fantastic dog and worth 4 hired men. She has saved my life (or serious injury) on at least two different occassions over her life time and is now enjoying a well deserved retirement.

It has been my experience that a Heeler is a rougher, tougher sort of dog both physically and mentally. This can be an asset with cattle but could be a problem with sheep as my Heeler might get too rough with them.

The B.C. we had were very intelligent dogs, trainable to do almost anything you have the desire and patience to teach. Excellent sheep dogs but I never had the feeling that if things got ugly they would stay with me. Having said that, how ugly could it get with sheep?

As a generalization I would say the BC needs more training and more continuous training (thus a dedicated owner) but is capable of doing more when done properly. The Heeler is easier to train and remains trained even if parked for a while but has fewer tricks in the bag so to speak.

To illustrate a difference: If you have sheep in a field and you want them in the barn. With a Heeler you walk out there, get behind them and then the dog gathers and pushes them where you direct. With a BC you send the dog to get the sheep then go open the barn door and stand there and watch. Perhaps give a couple of commands as the dog brings them in.

To a livestock protection dog a herding dog is a predator. You will have to introduce the herding dog very carefully. Our Great Pyrenees gradually got used to the BC's but I know some guys that always had to tie up their protection dog before running their herding dog.

Hope this helps a little bit. I stress "train the trainer" because otherwise a herding dog is a wreck waiting to happen imho.
Regards,
Dave.