Black-hair follicular dysplasia in dogs.

Black-hair follicular dysplasia in dogs of mixed breeding was delineated by hypotrichosis and dullness of most black regions of the coat. White regions remained full and lustrous. The abnormality was not grossly visible at birth but became evident after the 1st month of life. Among 15 offspring from 2 matings of an affected pair of dogs, each of 12 spotted pups developed the disorder in black regions; the remaining 3 were all white and appeared normal.