
I would say for a start they would be those breeders who breed to the breed standard, health test their breeding stock, and abide by their breeds code of ethics. the kennel club asked breed clubs years ago to drae up such codes as obviously different things appled to diferent breeds, such as age of first litters, how many litters and waht health tests.
I would always send someon to a breed club as anyone with a serious interest in their breed will belong to one or more of these clubs in order to stay abreast with issues concerning their breed, to share knowledge between members etc.
The Kennel club is really like the DVLC, deals with registraion matters, it is the manufacturers (Breed Clubs) that are the experts on their field.