I have a staff bitch that is expecting a litter of puppies that was bred with a lovely brindle boy.
The question i have is the parents of my bitch bonnie, are supposed to be of a pedigree back ground is there any way of going back further to find there parents, and can i get my bitch registerd

Only the breeder can register a litter of puppies, I'm afraid, and they have to come from registered parents.

As BennyBoo says, only your bitch's breeder can register her (you can't), and only if both her parents were registered. Unless you contact Bonnie's breeder and get her registered that way, your litter of puppies cannot be registered I'm afraid. Of course, the sire would need to be registered too.