Line Breeding

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All of the different breeds of dogs are a result of inbreeding. This is how the various breeds began. Inbreeding occurs through natural selection among a small isolated population or through the influence of man breeding selected animals to derive specific traits. Either way, inbreeding is responsible for setting enough of the dominant traits so that the resulting group breeds true to type.

A dog’s physical makeup, or what you visually see, is called the dog’s phenotype. For each characteristic, a dog has a pair of genes, one inherited from the sire and the other from the dam. A gene pair may consist of two dominant genes such as “AA”; a dominant and a recessive gene such as “Aa”; or two recessive genes such as “aa”. A gene’s alternate is called its allele. Only one member of a gene pair will be expressed in a dog’s phenotype. Genes are dominant or recessive to its allele and never a combination or this would compromise results. This discussion is what primarily influences the color, coat and furnishings of the Pudelpointer.

A dog’s genetic makeup is his genotype. Now, both members of the gene pair are expressed. When both of the gene pairs are the same, they are homozygous, such as “AA” or “aa”. It is the heterozygous genotype such as “Aa” that is responsible for most of the questionable heredity misunderstandings. It is impossible for a dog with a recessive phenotype to carry a dominant gene in its genotype as the dominant gene is always expressed if present. If recessive genes are rare in a breeding, it will usually be masked by the dominant genes. This is why line breeding concentrates the dominant genes of a specific ancestor or ancestors through their appearance multiple times on both sides of a pedigree. This spreading of desired ancestors is what helps to influence inherited genes from both parents to be identical and are called homozygous. If these genes are not similar, they are said to be heterozygous. Gene pairs that breed small gene pool breeds such as Pudelpointers must be homozygous for phenotypes and personality traits to be “true to breed”. Hunting instinct, color, and size are influenced by variable gene pairs and by making use of them; a breeder can select the desirable characteristics and avoid most of the undesirable ones. Homozygosity greatly improves the chance that the pups can, in turn, pass on the desired traits of the specific ancestor to their own pups down the line. To accomplish his kennel’s mission, the breeder must continue to select pups that display the desirable traits of the ancestors.

A common concern among many researching a new hunting companion is an avoidance of a breeding that was influenced by inbreeding. Through inbreeding a rare recessive gene can be passed from a heterozygous ancestor from both parents, which creates a homozygous recessive pup. This is how undesirable traits are developed from inbreeding. If a breeder is inclined to inbreed, the inbreeding coefficient (Wright’s coefficient) should be established to keep an accurate count of the same-appearing dog on a ten-generation pedigree. With a gene pool as small as the Pudelpointer’s, inbreeding should be avoided at all costs.

The Cedarwood Kennel’s line of Pudelpointers are the result of line breeding back to an extremely successful litter of pups that Johnny Shulkey produced in 1983. The two dogs appearing on our pedigree, Atom V. Shulkey and Adonis V. Shulkey, are 2 littermates from this famous breeding. They both can be found in the background of most all of our breeding stock, today. I wish I could take credit for the foresight of line breeding my dogs from these two dogs, but it was actually the combination of good luck and seeing Cedarwood pups earning eight NAVHDA Breeder’s Awards in a row that stimulated my research of genetics and the Cedarwood pedigree. The common denominator always returns to these 2 dogs on my present pedigree.

What we have learned from our past breedings is that a sound breeding involves three generations, going back to the great-grandparents; beyond that, the ancestors have little influence. We like to see the sire as the great-grandsire of the dam for a perfect line breeding (a bitch can also be used for this model). Occasionally we need to nick our line with an outbreeding to give our line a “bump”. Whenever we outcross our Cedarwood line to a top dog in a different family, we often get a heterosis bump, and often very exceptional dogs. This appears to be an outstanding way to combat the doctrine of retrogression, aka “drag of the breed”. For instance, when you breed two excellent dogs, the litter might produce a dog better than the parents, some dogs as good as the parents and also some dogs that are lesser than the parents. Likewise, if you breed two lesser dogs, most of the litter should be better than the parents. In other words, the breed tends to move to the center of the bell-shape curve and this is how the purebreds keep a steady pace, with minimal improvement. To avoid this mediocrity, our breeding program keeps the positive bump from another family and then breeds back to our line breeding to accelerate beyond the purebred’s steady pace.

Many breeders, including Cedarwood Kennel, who are conscientiously line breeding their dogs like to track the motherlines on their pedigrees. Motherlines refer to the whole of the bloodline of all the mothers on both sides of the pedigree. On our pedigrees, we like to see Adonis and Atom V Shulkey’s mother (Dulli VD Wilhelminger) appearing frequently on each side of the pedigree. Also, Cedarwood’s Calendar Girl as often as possible on each side also. Bob Wehle of Elhew kennels would have called these two females “blue hens” – females that a family of dogs could grow from. Some studies, in Germany, see the motherline success as coming from utilizing very important sex-linked genes present only in the DNA of the X-chromosomes of great-producing females. A male has 76 paired chromosomes plus an X and Y chromosome. The only place a male can inherit these important sex-linked genes is from his mother. When this male’s son becomes a father, only his daughters get this valuable X chromosome, never his sons. When the resulting granddaughters become mothers, the art of breeding lies in selecting only the male offspring that inherited this valuable X chromosome. These great-grandsons will be able to pass this sex-linked gene on to their get. This is all in theory, however, as there isn’t sufficient supportive data to define the theory as reality. This process also brings forth the influence of the stamen female or Blue Hen, which is the genetic component Cedarwood Kennels support. A somewhat more simplified explanation is the belief that 60-80% of a pups genetic influence has been derived from his mother. Using specific Blue Hens in a motherline concentrated pedigree is a much more traceable method of linebreeding, however. Afterall, if one is known to be a breeder, their first responsibility is to their mission or vision statement, which is in reality defined on their pedigrees. Back to Genetics