Many dogs have RD and in most breeds an ophthalmologist will say it is acceptable to breed the dog. However, in the Labrador Retreiver and Samoyed it is not advised to breed. These breeds will fail an eye CERF exam and should not be bred. The reason is that in these two breeds RD is an indication that they may be a carrier of OSD.
OSD is a severe condition that causes dwarfism and blindness at an early age.
We do have DNA testing available for these 2 breeds. One parent of a litter must be clear to prevent producing pups with this condition.
See more info here:
This is an example of a Labrador with dwarfism
If you are breeding either of these breeds mentioned above please do your genetic testing first to be sure one parent is clear.
This is just one disease important to test for in Labradors. The list is extensive and all should be done on at least one parent of a breeding.
Be a responsible breeder.