So you want to "rescue a pit bull..."?
Border collies were genetically hardwired to herd, pit bull type dogs were bred for high pain tolerance in drive, to fight dogs/hold large game, and for animal aggression, just as retrievers will always retrieve. They do not need to be trained to do these tasks- IT IS NOT ALL HOW YOU RAISE THEM. Much is determined by genetic makeup.
You can put a high level punisher in place to stop these behaviors, but genetics are hardwired...so is this really fair? Maybe just think a little more carefully about whatever dog you plan to adopt or purchase from a reputable breeder. Please keep a dogs’ purpose in mind and make sure your lifestyle will give them an outlet in some constructive capacities for these tendencies that they mostly cannot help. There are exceptions to every rule, but that’s what they are - exceptions. (Couch potato marshmallow bully breeds, lazy collies, chill retrievers, etc...) And yes, you can use positive reinforcement to encourage and redirect intensity into other behaviors, BUT, throw a collie in with some sheep, let a squirrel loose with your pit bull, and see what your retriever does when that school of ducks scamper by. Bet your treats won’t be so useful, then, dear friends. That latent desire to fulfill that drive is still there. You didn’t fix it. Sorry.
Plan accordingly so us trainers don’t have to correct behaviors that your dogs naturally are compelled to express, simply because it’s a hassle for us people to deal with.
If you want a border collie with working lines, you’d better live on a farm, compete in agility, hike a ton, or run distance several times a week.
If you want a bully breed, you’d better take that dog hunting, play a ton of tug, and/or do protection work and drive sports so that terrier dog has an outlet for their natural aggression. And maybe don’t get one of these breeds if you’re into dog parks? Or act so surprised when your dog wants to kill things.
If you want a retriever, don’t be surprised if that dog is whiney and anxious, bringing you items from around the house at all hours of the day.
Most dogs need a job.
Research different breeds, and please plan accordingly.
Or just get a pug, or a cavalier, hahah!