by Vicki DeGruy, Thunderhill Chow Chows
One of the most common misconceptions by pet owners is that inbreeding causes bad temperaments, deafness, cancer, hip dysplasia and all manner of horrid ailments. I've found that even some otherwise knowledgeable show dog people believe the same. To help clear things up, I wrote this ultra-simplified introduction to genetics that may come in handy as you try to understand what inbreeding is and what it's not:
Imagine you're drawing the winning lotto numbers for the week. Imagine you've been presented with two baskets of brightly colored balls with numbers on them. Your job is to randomly pick a ball from each basket and pair them together. You're to keep pairing up balls till the baskets are empty. You notice that some of the balls are perfectly-shaped while others have a chip or two. Those chipped balls are defective.
Imagine now that the balls are really genes, those little things within our cells that tell the cells what they are to be: eyes, ears, noses, hearts, hair color, etc. One basket represents Dad Dog's genes and the other is Mom's. To make a puppy, each parent donates a gene for each characteristic a dog can possibly have. Some of the genes are normal (most of them), others may be defective. They travel in pairs, one gene from each parent. If both the genes (lotto balls) are perfect, the characteristic they govern will be normal. If both genes in the pair are defective, the characteristic will be abnormal. To complicate things a bit, if one gene is okay and the other not, the characteristic may be normal and maybe not, depending on some other factors that we don't need to go into now.
In a lotto, the more numbered balls you have to work with, the more variety there'll be in possible combinations of winning numbers. If only a few balls are used, there will be fewer possible combinations. You might even be able to guess ahead of time what numbers will pair up.
When you breed two unrelated or distantly related dogs, it's like working with huge baskets of lotto balls. Lots of possible combinations, very random, because each parent's genes are different. Closely related dogs have genes that are similar, they share many of the same characteristics. Bred together, there will be less variety in the genetic combinations and the results are more predictable. You're working with a smaller basket of balls, so to speak. Experienced breeders inbreed in order to keep certain genetic combinations that they desire. The smaller the basket of balls, the better your chance of having your numbers come up.
Inbreeding, by itself, does not create new inherited problems. What it does, though, is increase the probability that any defective genes (chipped balls) the parents have will appear in the final combination: the finished puppy. It also increases the probability that the desired genes will appear as well, increasing the chances that the breeder will get the sort of puppy he is trying to produce. A knowledgeable, experienced breeder - the only kind that should be inbreeding in the first place - has taken time to learn his dogs' genetic makeups (what's in their baskets of lotto balls) as thoroughly as he can before breeding in order to determine whether a particular combination will be successful or disastrous.
Breeding successfully depends on the genetic quality of the dogs used. If you're using poor quality parents, the puppies are likely to be of poor quality whether they're inbred or not. The issue is not so much whether inbreeding is safe or not but how good are the dogs being used and how knowledgeable is the breeder using them. This is why I recommend you visit the breeders personally and see the dogs they use in their breeding programs for yourself. Are they sound of mind and body and are they kind of dogs you'd like to own? If not, keep looking elsewhere for your perfect puppy.
(previously published in "Quackers", the official publication
of the Novia Scotia Duck Tolling Retriever Club.)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~