That is absolutely not true and there are no statistics or studies to support that statement. In over 25 years of breeding, I have never seen a dog collapse or had one in my breeding program that did. In that 25 years, I know of one breeder who had a dog that collapsed. It was placed in a pet home and since they knew what the trigger was, the dog lived a normal happy life. Further, I know several breeders who have EIC tested their dogs and had them come back as EIC "affected" and to date, those dogs have never collapsed. By the same token, I have had TVD affected dogs and know of plenty of breeders who have had TVD affected dogs. Many of these dogs were only diagnosed after an echo. You can breed around EIC. If the test is correct, then you need to only have one parent be a clear. You can't breed a TVD affected dog to a "clear heart" and expect to get all clear puppies. OFA could potentially give a CHIC to a dog with a bad heart as long as it has an EIC clearance. This boggles my mind.
I am not in the LRC, but am in another breed's parent club health committee. The quandary for the LRC appears to me to be that even the cardiologists are not agreeing on what constitutes TVD or abnormal flow and on a protocol. Common sense has to prevail on this and any other health issue for which there is not a clearcut test, such as epilepsy, same as it had to back before there was OFA. Folks have to, on the one hand, not be kennel blind, and on the other, not throw the baby out with the bathwater. For EIC, there is a widely accepted genetic test. It may or may not be perfect, but it way farther than we are in knowing what to do with TVD. If your lines and those of your friends are riddled with TVD, that is tough, and one has a hard time when line breeding AND out crossing if we don't know where it came from. Yes, now you will probably say that there is not a genetic test for phenotypic hip dysplasia, which is true. The difference is that for many decades there HAS been a Hip Dysplasia protocol via OFA. HD on OFA was a start and increased peer pressure against those who thought of breeding dysplastic dogs. Ideally, the breeders themselves will police the gene pool to some extent, using common sense, and insisting on whatever you believe is the way to breed Labs with clear hearts. If bitch and stud owners insist on at least an auscultation and/or echo that is clear, that is a start. Peer pressure and money talk loud and clear.
The Chic never meant a thing to me. When I recieved them they just go in folder. With Stud dogs don't care. We have the clearances and we have copys of those. Who ever needed this ?
Considering that CHIC only requires that you TEST for the anomoly, and pass or fail, I think everyone needs to have their antennaes up to understand the results. So yes, in a sense, it's meaningless if people dont understand. I am in full agreement w/ Laurel that cardiac should be included. I think PRA should be included if EIC is. I've not submitted either results to OFA in years past however. I do it for my information, post to my own site, etc. I was a bit surprised for the added EIC req. Anne
PRA and EIC should not be included because the status of both can be determined by parentage and therefore testing is not always necessary. Also, since both conditions are caused by a recessive gene, you do not have to test your bitch if you are breeding to a dog who has tested clear.
EIC and PRA are genetic tests whereas hips, elbows, and cerf are phenotypic tests which need to be done every generation.
TVD test is also phenotypic but is the problem prevalent enough so that all breeding animals need to be tested? I will not breed to a stud dog who is not TVD tested but I only have my vet listen to my girls.
I have a dog who has collapsed. The collapse was textbook EIC so I had her tested. It came back affected.
She has not collapsed since but I am very careful not to work her too hard, and not at all during hot summer days. Knowing that most people do not work their dogs that hard, I suspect that lots of people have EIC affected dogs and will never know it.
This is a good thing because that might mean many cases of EIC are not that bad for the average pet owner or typical show breeder. BUT, some people actually like to work their dogs hard and our breed should not only be able to handle that but should thrive in those conditions. Since EIC is so easily tested for, and so easy to breed around, there is no excuse for not testing for it if status is not known....especially stud dogs.
But again, since you can know your status by parentage, and you can breed to a clear stud dog with no risk of affected pups, not everyone has to test and therefore it should not be part of CHIC.
Since TVD is not easily tested for and can be debilitating, it is a valid question to consider if TVD testing should be part of CHIC. In my case, I have never bred a case that I know of in over 25 years. But, I am smart enough to know that my personal experience alone does not constitute a scientific study. I would love to know how prevalent TVD is.
If you're only having your vet listen to your girls, you're missing TVD. I had a bitch who cleared twice by auscultation - once at one year and once at two years - yet she failed her echo with mild TVD not long after the second clearance. It shocked both me and the cardiologist.
So, with mild TVD, dogs (including hard working dogs) can live a normal life??? The problem would be that doubling up on it could cause big problems???
My understanding is that TVD is polygenic, but at least some of the genes involved seem to be dominant???
I was hoping someone would answer those questions. I hope the way I worded them didn't come across as sarcastic and therefore insincere. I really would like ot learn a little more...
Auscultation may not pick up mild or even moderate TVD. And yes, a dog with mild to moderate TVD can live a normal life. I have a dog with moderate TVD and he is my most athletic and active dog. I hope to have him for many years but the reality is that with TVD I could lose him at any time. It could be a slow decline or he could die suddenly. I know breeders who experienced both. Unfortunately, the mode of inheritance is not known. With my TVD affected dog, the cardiologist could not hear the murmur with a normal stethoscope even though TVD was just diagnosed through color doppler. She was only able to hear it with a pediatric stethoscope.
You can get TVD with two color doppler clear parents. If you breed a dog with TVD, you will likely have multiple cases in the litter. I know of a litter where the sire was clear and the dam was affected and the entire litter had TVD. This isn't always the case. TVD is very complicated and very frustrating. I know a cardiologist who is now suggesting that a much more precise digital stethoscope should be used for auscultation but I don't know how many vets have them. I know the new cardiologist in my area did not have one when doing a heart clinic.
Thank you.
Is there any data on how prevalent this may be?
I am not aware of any data - but I know many breeders have had it at one point or another.
I have a TVD affected bitch - had clear auscultation from our Vet, clear auscultation from cardiologist, failed the echo. Had one litter between her auscultation and the echo - all pups cleared an echo at 12 months.
The board certified veterinary cardiologist that does my echoes has quoted that 20% of dogs that pass auscultation go on to have TVD diagnosed during the echo.