Most people seem to have a great interest in knowing what breeds their mixed breed dog has coursing through his makeup. Sometimes this information can aid in understanding behavior and determining training techniques. Sometimes it is helpful in health and grooming matters but I suspect simple curiosity drives most inquiries.
During the last few years, DNA testing has improved to the point of being able to identify the breed of a purebred dog with 99% accuracy. In fact, the AKC requires DNA testing before registry, in cases where puppies' parentage is in question. And scientists claim that computers will soon be able to differentiate the breeds in a mixed breed dog by analyzing DNA samples.
Until that time, and one wishes to pay the fee for DNA testing and analysis, we have to rely on educated guesses. Shelters that operate on tight budgets will, obviously, not be interested in the added expense. In some dogs, a dominant breed can be apparent and easily recognizable but in other cases, shelter workers have to settle for identifying a breed group such as hound, terrier, northern, etc. They take many characteristics into consideration-size, color, color patterns, coat length and texture, bone structure, musculature, facial features, ear shape and carriage, tail shape and carriage, personality traits, energy levels, gait, and any special features such as eye color, tongue color, webbed feet, and wrinkled skin. Puppies, who are changing drastically as they mature, are the hardest to identify.
Dog experts cannot always know when a combination of several breeds may be creating the appearance of another breed. Sort of like when an artist mixes colors. Red and blue makes purple but you can also add a bit of yellow and still get a shade of purple. At the same time, blue and yellow creates green, which when mixed with red, will create brown. So, when you consider that your mixed breed dog could have had mixed breed parents who had mixed breed parents who had mixed breed parents, identification gets tricky indeed. Even with years of experience and a practiced eye, mixed breed identification is not easy or, by any means, accurate.
But, more importantly, no matter what your dog is, he will love you no matter who you are.