The difference is in deciding whether to be a reputable breeder or a puppy mill, and whether to contribute to the good of the breed, or to not care about dogs and just be in it for the money.I was doing some research on breeding, and some breeders test their dogs thyroids, eyes, ears, joints, and disease, while other breeders don't do anything of the sort, but charge the same amount of money. What is the difference?
I can't imagine anyone who cares about the dogs mating two untested adults, and hoping for the best in the offspring. You can load the dice in your favor by testing, and by not breeding dogs that don't meet minimum standards.
The Guide Dog associations are going to require that you do testing on the parent dogs, at the very least they want to see hips, elbows and annual CERF, and will probably also want an annual CBC with thyroid panel. There is a new DNA test out for pcrd-PRA, and dogs with poodle ancestry are often tested for vonWildebrand's(sp?). They may want to see OFA cardiac certification, too. I had GDA's requirements written down at one point, but have misplaced them.
You'll have to consider the expense of establishing and maintaining a web site to market your puppies, the cost of a digital camera so you can post regular photos as the puppies grow. There's a whelping box to purchase or build, a puppy scale, worming and shots, spay/neuter surgery if you choose to go the ESN route, and I'm just scratching the surface here. This is an Expensive proposition! If there are medical problems or the bitch needs a Cesarean section, bring your wallet. And you love doing laundry three times a day, right? (Me either.)
I'm not trying to sound gruff or to discourage you, just to plead that you research this carefully prior to taking the leap. I guess your question what is the difference sort of hit me as asking why you should bother to test the parents, and there are Plenty of reasons! One, so that you will produce the healthiest possible puppies, that will have the best shot of getting through their lives without serious illness or pain. Two, so that you can market your puppies with your head held high, and honestly answer questions about health testing, and health of the parents. Three, to set yourself apart and build a reputation as a responsible person, and not as a puppy mill. Puppy mills don't usually go to the expense of health testing, so if you have purchased your dog from a puppy mill, you have no idea what is in her background, or what might lie ahead for her. Do you feel comfortable taking that risk?
best wishes to you, and let us know what you decide to do.