ABSTRACT
This chapter gives the reader an understanding of the diversity of diseases in the domesticated animal populations which are available for investigations in basic pathogenic mechanisms of skin disease. In color dilute alopecia/dark hair follicular dysplasia this process appears exaggerated to the point where there is disruption of matrix cells, a feature which could be explained if in these two diseases melanocytes did not become senescent as hair follicles entered telogen. Although more aggressive putatively histiocytic diseases are recognized infrequently in most canine breeds, only the histiocytic proliferative diseases of the Bernese Mountain dog have a confirmed familial basis. The value of defining the molecular alterations associated with the development of the histiocytic proliferative diseases of Bernese Mountain dogs should be obvious, considering the infrequency of these diseases in humans and their often poor prognosis. To this end, many of the unique, heritable diseases present in kennels and barnyards stand as an untapped resource for knowledge in dermatology.
