It's not just about testing your pup, you need to know the health & genetics of her parents & grandparents & so on.... You can also do research on the things I mentioned & will most likely be shocked at what you find but these are the things our babies can be afflicted with & just because your pup appears to be healthy on the outside does not mean that she will not pass any of these horrible things to her pups. If you intend to be a breeder then you need to do lots of research & save your money to purchase some champion healthy, free of genetic disorders & deformities parents. I know that you would never want to pass on anything as horrible as the things I mentioned to pups & other owners as they are heartbreaking & Very expensive for the owners & painful & life threatening to the pups.
This is most likely why your vet suggested for you to spay your pup. Breeding should def be left to the pros.There are plenty of badly bred pups in this world who need homes already & I'm sure that you would not want to add to that population.