Here is a link to the OFA website where they keep a list of all the labs that do genetic testing for Dog diseases. The costs for these tests are much lower than ever before. Breeders and owners of purebred dogs will find this very helpful to plan their dogs future.
I have tested my dog for a Collie genetic disease (MDR1) for which he is a carrier and affected. But knowing he has one copy of the MDR1 gene means I can adjust the dose of certain drugs to prevent overdose and avoid other medication completely. In my case knowing avoided allot of possible harm. Since he is a carrier is out as a breeding dog and has been neutered. 70% of Collies have the defective gene causing MDR1 (Multidrug sensitivity) so the only way to reduce how many Collie’s get this genetic disease is to not bred all dog with a copy of the gene. Can’t see this disease on the outside of the dog. The only way is through a DNA test or when in a crisis of drug overdose which can be lethal. I would rather know.
This link is for breeders and others interested in the details of reproduction of the dog. Link is to start page with this of chapters. Choose which you want to learn more about. This is a Veterinary level course in dog reproduction. If you have a Bitch or dog who varies from the average or normal development, seek out the advice of a Board Certified Theriogenologist who is a specialist in canine reproduction.
Follow this link to find charts that explain how the female dog works