I had a pure (registered) dogo a while back that was just as you describe yours. Both parents of this dog are exceptional catchdogs, and come from WELL established lines...bred to the hilt.
I had it in my thick head that this dog WOULD eventually come around and make a catchdog. I tried EVERYTHING imaginable over a few week period to get the dog to even show a HINT of prey drive. At wits end, I tried the make-it-or-break-it method as described above hoping a large, mean sow would flip on his switch. I put him in a small (5' square) pen with the sow and she hit him right off. He squealed and flipped over on his back. She never hit him again, but for the next few mintues everytime she would even turn her head his way he would squeal like heck and just trimble. I pulled that dog out of the pen, counted my losses and chalked another one up to a lesson learned. That was the beginning and probable end to my dealings with pure dogos.
I would try this as my last ditch effort also worked for me. He turned out to be the best catchdog I ever owned. It was a do or die kinda thing for him. luckily for him he knew his optios. LOL
