Mixed-Breeds Don't Suffer From Exaggerated Physical Traits. One of the things that breeders try to influence when breeding purebred dogs is how the dogs will look. Purebreds are typically large or small, a breed may be known for long coats or short coats, and they typically boast other distinctive physical features. Owners who are not interested in these traits may be able to benefit from the reduced cost of owning a mixed breed dog.
Because each purebred breed was created to look a specific way, each breed has its own unique set of physical characteristics. In some cases, these traits have been emphasized to the point that they frequently cause health problems for the dogs of that breed. For example, some dog breeds, like Bulldogs, Pugs, and the Pekingese, have such short noses that it causes breathing difficulties. Although the breed clubs and registries responsible for how these dogs look seem to cherish these features, in some breeds these physical characteristics are so exaggerated and create such health problems that if they were wild dogs these traits would likely be considered a deformity.
In mixed breed dogs, most physical characteristics are moderate. Even if you breed a purebred dog with extreme physical characteristics to a dog of a different breed without the same extreme trait, or to a mixed breed dog, the offspring probably won't have the same extreme physical characteristics.
For example, if you breed a Bulldog with a mixed-breed dog, the offspring usually won't have the abnormally short nose of the Bulldog, and therefore wouldn't be prone to the same breathing-related health problems that Bulldogs experience. Instead, the puppy's nose would be a blend of the many genes that control each of its parent's nose and would likely appear as a moderate blend of how the two parents’ nose looks.
In this way, mixed breed dogs avoid the exaggerated physical traits that create associated health problems for some purebred breeds. Most mixed breed dogs are of medium size, with medium-length coats that shed a moderate amount. If you are looking for a companion dog with average physical characteristics, a mixed breed dog is likely to provide the blend of traits you are seeking at a potentially significant cost saving when compared to the price of a purebred dog.