Nasal depigmentation ('Dudley nose') is a common non-pathogenic disorder of the nasal planum of dogs characterized by depigmentation of skin.
A genetic predisposition has been noted in a number of breeds including the Australian Shepherd, Afghan, Alaskan Malamute, Bernese Mountain Dog, Doberman Pinscher, German Shepherd (White), Golden Retriever, Irish Setter, Labrador Retriever (Yellow), German Short-haired Pointer, Miniature Poodle, Samoyed and Siberian Husky.
The precise cause of this loss of pigment and colour change is not known but it is possibly a form of vitiligo. Presumably the condition is intimately linked to pineal gland and/or melanocyte activity.
In some individuals the amount of pigment present may change from time to time, in others it remains depigmented.
There is no recognized therapy for this condition which is otherwise not harmful to the affected patient.