Conversely, a sire and dam both with genetically induced hearing loss could produce a litter all with perfect hearing. Another conclusion is that the defective gene is linked to the gene controlling color. The more Dalmatians were bred to have small ticking-like spots, as opposed to large patches of color, the more deaf dogs they produced. In bird dogs, the whiter the dog the higher the probability of finding genetically induced hearing loss. Many breeders have been selecting for more and more white and less color, unaware that they were also selecting for bad ears.
Tests exist that can be done on young dogs to determine if their hearing is working properly.
During the test their brain wave reaction to a sound is recorded. However, the equipment needed is expensive and usually only available at research centers and university veterinary programs. There are a few simple tests that people can perform to determine if they have a hearing impaired pup. Obviously, a dog that is totally deaf is fairly easy to pick out. It is the pups that can hear with one ear that will often fool you.