What is outcrossing?
Outcrossing is where the sire and dam are totally unrelated, preferably for three or four generations. The true form of an outcross is between two entirely different breeds because in reality the members of most registered breeds come from a common ancestor (althought it may be many, many generations back). It is very rare for outcrossed puppies to be uniform in appearance. Usually there are a very large ranges of sizes, coats, colors, markings, and other distinctive characteristics. Outcrossed litters are generally heterozygous, and do not reliably reproduce themselves, so even the nicest puppy in the litter may not later produce the best puppies.
Outcrossing is generally used to introduce something new to a line — a better head, better colors, better front, etc. Usually the puppies retained from these breedings are bred back into the breeder’s original line to standardize them back into the line’s general characteristics and reproducibility — with the one desired characteristic. The tricky part is that other characteristics may come along for the ride!
If you are dedicated enough, you can eventually continue breeding by outcrossing alone (but don’t expect instant or quick results). You should pick dogs that complement each other well and are similar in general appearance. This is a long hard road to eventually developing a line. Through outcrossing, many health problems can quickly be eliminated (or just as quickly added into your breeding), but usually you do sacrifice some show quality and producibility.
You have to remember that dogs that appear totally healthy may be carriers of genetic problems. To find this out, test mating is done to a dog that is affected with the genetic problem (resulting usually in puppies that are both affected and non-affected carriers) or by inbreeding to a related dog that also doesn’t show the signs of being affected (usually littermates are used) this will usually result in some puppies free of the problem, some puppies as carriers, and some puppies affected if both dogs carry the problem gene (this is not as accurate as breeding to an affected dog, but you are less likely to have to put all the puppies down).
There are variations on outcrossing. A “true” outcross could be a dog that has totally unrelated dogs bred together throughout the pedigree. This is very rare. On the other hand, “linecrossing” is a form of outcrossing where dogs from unrelated lines are bred to produce a new line. The sire and dam are usually very linebred from their prospective lines and the resulting puppies are varied in apprearance, some looking like the sire’s line and some looking like the dam’s line and some looking like mixtures of both lines.
Wilcox, Bonnie (DVM). “Things to Think about Before Breeding Your Dog.” DVM, printed in various newsletters.
