Types of Pedigree Breeding

Below is a sample pedigree showing 3 generations.

Gen 1         Gen 2         Gen 3

Paternal Grandfather

Father

Paternal Grandmother

Your Puppy

Maternal Grandfather

Mother

Maternal Grandmother

In-Breeding

In-Breeding is when a breeder chooses two very closely related dogs to breed to each other.  Brother to sister, mother to son, father to daughter.  In-breeding takes place between two individuals no more than one generation apart.  Brother to sister is the closest possible form of in-breeding one can do as each of the offspring has identical DNA from their parents.  In-breeding should ONLY be performed by veteran breeders who have worked with the same lines of dogs for many generations, and has a extremely good knowledge of all the genetics in the family of dogs they are breeding.     A breeder may choose to in-breed two individuals to "fix" type by combining virtually the same genetic material.  Generally speaking, I do not recommend in-breeding.

Line-Breeding is when a breeder uses animals that are related, but not closely.  Grandfather to granddaughter, cousins, aunt to nephew, etc.  Line breeding goes beyond the first to the second generation at least, and sometimes beyond.  Any further back than 5 generations, with no more than one related dog, is barely considered line breeding any more.  Line breeding allows the breeder to develop a specific "look" that they desire in their line.  By breeding related animals with the same look, breeders can "fix type".  Some breeders have become so accomplished at fixing a specific look that their dogs are instantly recognizable to a trained eye.  This is what most breeders desire to do in their breeding program, and it can take several generations.  It was a combination of line breeding and in breeding that breeders would have resorted to first to develop any new breed.  Later after certain qualities were breeding true for a few generations, an outcross would have been used as well for both new needed qualities and for "hybrid vigor".

Out crossing is the breeding of two unrelated animals.  While you may find that there is one common ancestor in the 6th generation, that particular dog is so diluted in the pedigree that it can barely be considered line breeding.  The outcross will allow the breeder to bring in qualities their own line does not possess, whether it be a look or a health benefit. 

Most breeders use a combination of line breeding with occasional out crossing.  An experienced and educated breeder knows when to outcross, and to which dog.  If a breeder has overall good type, health and temperament, but perhaps the pigment is not as dark as she likes, she may choose to breed to a male that possesses good pigment.  From the resulting litter she will then choose the puppy that most closely resembles the look she wants to achieve AND has the pigment from the sire.  This puppy will later be used in her breeding program with her own line to hopefully introduce pigment into future generations of her line.

All three types of breeding can be dangerous. Out crossing brings in a completely new pair of genes to the DNA.  This new pair, if properly matched to the old pair, can result in the qualities that you want, or even faults you did not even know existed.  In-breeding over and over is just plain stupid and I know of NO breeder that does this.  Line breeding without ever out crossing can result in a loss of good health and/or temperament.

The basics of genetics is that genes are matched pairs.  One gene comes from the mother, and one comes from the father.  One is dominant and is "expressed", and the other is recessive and is unknown.  Different qualities - eyes for example - can be controlled by a single gene, or multiple genes.  One gene will define the color of the eyes, while another may define the size and the placement, or just the size.  There are a lot of unknowns with regard to genetics in dogs, and most of the genetic research has been done to combat health problems, and not to assist breeders in fixing type.  One way to tell if the parents possessed a recessive gene is to breed them together and see what they produce.  Take light eyes for example, a dark eye is always going to be dominant in the Kuvasz breed.  If a given pair of dogs produced at least some puppies with light eyes, the breeder knows that BOTH parents possess the gene for light eyes and at least some of these puppies were unlucky enough to get the light gene from both mother and father. It is important to note that even the puppies that have dark eyes in this litter, may still carry the gene for light eyes.  Not all genes work this way though - what we call simple recessives, so it can get complicated.  Breeders that have thoroughly researched pedigrees have a better chance of predicting what a specific breeding will produce, both with regard to type and health.