I reckon if you breed your dogs you should only breed from worker to worker to keep that working gene pool, too many people breed from just about anything just to cash in because they are fashionable,its not about K,C Reg.its about the working line ,in short the dogs thenselves,There is no point when out hunting to have terriers that look smart and have a good show pedigree but have little or no hunting instinct or ability,backing my arguement to breed only from working stock,Ihope you all agree.