Type and Outcrossing
Article by Marion Coffman
All living things are made up of self-contained structures called cells. Reproduction is dependent upon a sequence of events that take place within a single cell. These cells contain within them a nucleus and within the nucleus are tiny thread-like structure called chromosomes. The chromosome pattern for each individual is unique to that individual and is created at the time of conception when the sperm of the male unites with the ova, or egg, of the female. The chromosome within a cell varies in number but the number is always even because the chromosomes occur in identical pairs. Both the ova and the sperm are known as gametes and contain one of each pair of chromosomes. During the process of chromosome pairing which occurs in the initial stage of cell division, called meiosis, there is a mingling of the chromosomes which allow a part of one to replace the corresponding part of its pair, making the newly formed chromosome different in gene composition to those of the parent.
Meiosis allows the breeder to understand why, for example, brothers are not identical and why breeders do not get the same genetic material using brothers of an excellent dog. The chromosomes have within them molecules which are divided into sections known as genes. As the chromosomes are paired, so are the genes. Both genes of a pair may be the same, or they may be different, with one half of the that pair being more powerful that the other half. The genes determine the eventual size, color, temperament, and other basic characteristics and behavior patterns of an individual. The endless variations between the individual dogs are the result of the possible combinations when the chromosomes of one parent, composed of his unique pattern of genes, unite with those of the other parent.
A prepotent dog will have a high proportion of the dominant genes in his, or her, make-up. Those dominant genes may be in form of head type, tail set, and even temperament, among others. Pepotentcy can also apply to a dog which produces a high proportion of top quality offspring whether they resemble the parent or not. This is usually only true when the parent is the result of high quality line-bred parents himself. Many high quality specimens which are the product of outcrosses, or combinations of inferior parents who just happened to click, are not able to reproduce themselves.
Some breeders, without utilizing the advantages of line-breeding seem to have a remarkable amount of similarity of type in the dogs they produce. This probably is simply due to the fact that even when outcrossing, they have selected a particular type, similar to their own, to breed to. Type would rapidly be lost however, if that breeder is incapable of selecting type from his litter in order to continue to produce consistently high quality dogs in the next generation. Providing that high quality dogs whose appearance, temperament, and hunting abilities all come within the Vizsla standard, there is nothing wrong with a breeder producing different head types, for example, as this may provide future breeders with suitable dogs to breed to which are capable of counteracting deficiencies in their lines.
There is no point on relying on a pedigree to provide all the information on desired factors in a recessive form because the main object of outcrossing is to acquire dominant genes for future use. These desirable factors can then be brought back into that breeder's line if the outcrossed dogs are bred back to their close relatives. If a breeder is happy producing a litter which only contains a single outstanding dog, and the rest of the litter is poor quality, he will never understand the true meaning of type. If however, consistent quality over the long run is what the breeder truly is interested in seeking and attaining, he cannot achieve it by constant outcrossing, since even an outstanding outcrossed dog is less likely to be a consistently good producer than an outstanding linebred dog would be. A breeder HAS to assume the responsibility of breeding only the best in guaranteeing that future generations of breeders will have the best to also breed to.
--Posted 1998 with permission