We begin this article by first defining the word Consanguinity.
Inbreeding The production of offspring by parents more closely related than the population average. Genetically, inbreeding increases the portion of homozygous genes in the inbred population.
Line breeding is a form of inbreeding in which an attempt is made to concentrate an ancestor’s heritage, or an ancestor’s line into a herd.
I am very happy to share a topic with those interested in defining this topic of canine breeding. As a geneticist and master breeder, I’m presenting this article because so many people in the dog business are breeding dogs and you always hear the comment, “Oh, he’s inbred to his family.” Well, I am sharing this article with you so that before you comment, you at least know what the words mean and how they can be used in a positive way to help the breed we love so much, the Jack Russell Breed!
Inbreeding is a mating system in which offspring are produced by parents more closely related than the average for the population they came from. Example A: The mating of a father with his daughter
Example B: The mating of a full brother with a full sister.
These procedures are avoided because past experience has shown that inbreeding is generally associated with the appearance of genetic defects and a general decrease in vigor and performance.
In humans, children of first cousin marriage are believed to be doomed to physical or mental deformities, and this belief is why we have laws prohibiting the marriage of close relatives.
The genetic effect of inbreeding is that it makes more gene pairs in the population homozygous, regardless of the type of genetic action involved. All phenotypic effects of inbreeding result from this single genetic effect.
Inbred animals are usually less able to cope with their environment than non-inbred animals. This is demonstrated by their ability to reproduce and litter size decreases along with slower growth rate and small body size at maturity. You will also see a weakening in the immune system which will cause more sickness and disease within these inbred individuals. Some of the other negative effects that we Jack Russell breeders really need to look at are the jaw line, how the teeth line up in our puppies and by which families and the individual we use can identify progeny with any other early defects.
We now turn to the topic of online parenting and its benefits. Line breeding is a form of inbreeding in which one attempts to concentrate the inheritance of one ancestor, or a line of ancestors, and it is usually a male rather than a female because a male usually produces many more offspring than a female. Line breeding is usually a mild form of inbreeding directed towards an ancestor often involving the mating of half-siblings. It can also be used as close as a grandfather-granddaughter pairing or an uncle-niece pairing. Once again, you will increase the genetic traits of the bull you want to use. I believe this method will be beneficial in helping to understand the definition and its use in any breeding program. But again, we must always strive to produce a structurally correct and genetically sound short-legged Jack Russell Terrier that we can all be proud of.
For example, some of the characteristics to avoid when mating our short legged Jack Russell Terrier are excessive back length and poor quality legs that are not straight and healthy. We would always prefer a dog whose ear fits close to his head and folds down, not up. Once again, we need to look at the jaw line for upper and lower bites. We must also take into account the depth of the body and the opening of their rib cage, after all this is where the puppies will be taken. Again, you want a dog that has a wide base width when viewed from behind. This also affects the birthing process. And again, you want a prominent vulva on your females because the more correct we make our female dogs, the longer their reproductive life will be and their overall health will improve. This again will ensure you and your client a puppy that you will both be proud of!
