I have a question for you seeing you train dogs,wich I also train mals in ring sport, is a good dog working for you or working for itself? I've seen great dogs work well for one guy then get handed over to another and works no different.but then again I've seen the opposite also..but I've seen more high level dogs work for who ever just the same and didn't care as long as it got to work. And as far as the mange goes on a young pup it's not a good sign, and I agree see what you can do to see if it's 100% treatable. But chances are it very well may come back.but that type of dog should never be