I wondering how the cardio clearence works? For example what if only the male had cardio clearence, female never had it done. Does it make any difference in the pups affected or not? I hope this makes sense!?

Sorry, it doesn't work that way... Cardiac disease, specifically TVD, which is what I assume you are asking about, isn't a simple recessive. It would be much simpler and easy to breed around if it was!

Your question isn't clear but I will assume I understand what you mean. All the OFA cardiac clearance means/does is that the dog in question does not have TVD itself. We have no specific facts or correlation on how the disease is passed or how it manifests. All the clearance is showing is that as a breeder we did our due dilligence to check our dogs and make that good faith effort to NOT breed dogs with clinical signs.

The general school of thought is that TVD's mode of inheritance is dominant with incomplete penetrance, which means only one parent has to pass on the gene to get an affected, but a dog who does have the gene can be anything from totally unaffected to drop dead.

So bottom line, no, only one parent checked doesn't mean anything - only slightly increases the chances of getting a litter with no heart issues.

What they said already. The best you can do(at this time until we know more) as a breeder, to help insure sound puppies, is to make sure parents are clear through color doppler/echo not just auscultation.

I totally agree, echo color dopplers are the best test. Then we as breeders need to do research of the pedigrees. If a known TVD producer (or related to one) is in the bitch or stud dogs pedigree, you're taking a chance. If you add another to it, it's a larger chance. If you double or triple up on that same dog, you're looking for problems and just might have them.

So yes, do your dopplers, make sure the stud dog has one done by a cardiologist and try to research pedigrees as well as you possibly can. Auscultation alone is a waste of time and money.

If you need help with pedigrees, ask your trusted breeder friends privately about the stud dog you're considering and let them see your girl's pedigree.

Even TVD clear by echo Labs can produce get that has TVD. There is a better chance they won't if they have an echo color doppler.

Agreed, I love what you said. You sound right on with alot of common sense. Can't beat that.