DNA TESTING – THE WAY FORWARD WITH CARRIERS
A BREEDER'S VIEW
In Border Collies, testing to date has mostly been done by owners/breeders of Kennel Club registered dogs but over the past few years more International Sheep Dog Society members are getting involved too. Currently they tend only to test for CEA/CH (Collie Eye Anomaly/Choroidal Hypoplasia) and SN (Sensory Neuropathy), but hopefully in the future they'll take on board the other available tests as well. Most importantly, I'd hope that breeders from every walk of life who currently don't bother to test at all (for any disease) will wake up and join the responsible ones who do!
I've been asked on numerous occasions why we should test and the obvious answer is - to protect future generations of our breed, whether it be the Border Collie or not. There can be nothing worse than discovering you've produced a pup affected by a painful, even fatal disease. In many cases, that will also mean watching a pup start to suffer as a disease takes hold, since few will be prepared to have animals put to sleep until they absolutely have to. Often a pup will be in its new home, so a distraught owner has to cope with the result of the breeder refusing to test. There can be no excuse for creating suffering when we need not......
The brilliant thing about DNA testing is that it's a superb tool for breeders when used wisely. Yes we'd all love to have every test return a clear result, but since we know that won't happen (not yet at any rate), we can use our carrier results to go forward carefully. In the case of a non fatal disease such as CEA we could even use affected dogs, if their merit otherwise warrants it, although I can hear people saying 'there will be other stud dogs/brood bitches as good who aren't affected' and that's a very valid opinion, but just for the moment I'm only considering absolute practicalities. The important thing to remember is that any carrier or affected MUST ONLY be mated to a clear partner. The worst scenario in the resulting litter is that we produce more carriers (which in turn must of course ONLY be mated to clears) but we could equally be lucky and produce a few clears to carry our lines on with. Gone are the days when we had to 'throw the baby out with the bathwater'. There is no guesswork required now - we have the DNA proof and can hang on to those precious lines we've spent years developing. Of course, before being included in any breeding programme, pups from matings where one parent is a carrier MUST themselves be tested to establish their DNA status. We now have the knowledge to ensure that carrier never meets carrier in a mating again, nor must we mate carriers to untested partners, since that reintroduces those terrible risks we've all worked so hard to eliminate and in fact makes the testing we’ve done up to that point a useless exercise.
Personally I wouldn't now breed from any untested bitch, nor would I use an untested dog, because I wouldn’t have a clue what I might produce and ignorance is definitely NOT bliss! Another side of the coin appears where owners of clear stud dogs won't accept carrier bitches for matings. It does occasionally happen and while it’s undoubtedly their choice and right, I find it very short-sighted. How else will responsible breeders be able to retain their lines while clearing them of the carrier gene? Any prospective mating should be considered from the usual standpoint of suitability of course, but I (and many other stud owners) don’t see carrier status as a problem when I receive stud enquiries for my clear dogs. Luckily we live in enlightened times and most breeders are looking forward positively to a time when these diseases are a thing of the past and are willing and able to help others. In the meantime there is no stigma attached to producing carrier pups since these pups will never themselves develop the disease. The golden rule, the way forward, is very simple - never breed a carrier to anything but a clear, whatever the disease and whatever the breed.
Sheila Gay © 2011 ~ updated © June 2018
© Darian Border Collies ~ Sheila Gay. All rights reserved.
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