Vu,Prmurv zyxwvutsrqponmlkjihgfedcb Drrmutoh~y. zyxwvutsrqponmlkj VOI. zyxwvutsrqponmlkjihg 2. NQ 2. pp 69-83, 1991 Printed in Great Britain. 095Y 4493191 zyxw $5 00 zyx + 0 00 zy t ESVD and ACVD Black Hair Follicular Dysplasia in Black and White Saluki Dogs: Differentiation from Color Mutant Alopecia in the Doberman Pinscher by Microscopic Examination of Hairs ANN M. HARGIS’, MICHELE M. BRIGNAC’, FAHRI A. KAREEM AL-BAGDAD13, FRAN MUGGL14 & ALAN MUNDELL’ DermatoDiagnostics’, Edmonds, Washington, U.S.A., Dermatology Consulting2, St. Gabriel, Louisiana, U.S.A., Louisiana State University3, Baton Rouge,Louisiana, U.S.A., Sumner Veterinary Hospital4, Sumner,Washington, U.S.A. and Animal Dermatology Service’, Seattle, Washington, U.S.A. Veterinury Dermatology 1991; 2: 69-83 Abstract-Four black and white female Saluki puppies developed variably severe hypotrichosis in black haired areas. Histologically, follicles in black haired areas were dilated with keratin and clumps of melanin pigment, and were irregularly shaped. Melanin pigment was also clumped in hair shafts, basal layer of epidermis, epithelial cells of hair bulbs and macrophages around follicles, especially at the base. White haired areas were normal grossly and histologically. Light microscopic examination of dehydrated and cleared primary black hair shafts from one Saluki with black hair follicular dysplasia and primary blue hair shafts from two blue Doberman pinschers with color mutant alopecia revealed that the blue Dobermans had many more visible macromelanosomes than the Saluki. On scanning electron microscopy, cuticular abnormalities were identified in some white and all black hairs from the Saluki. Several black hairs had shallow, oval defects in the superficial cortex. Blue hairs from one Doberman had similar, but more extensive changes. Key Words: Color mutant alopecia; Doberman pinscher; Follicular dysplasia; Hair follicle; Hair; Saluki. INTRODUCTION Black hair follicular dysplasia in dogs is a rarely reported disorder affecting growth of black hairs, with sparing of white hairs. The term, “black hair follicular dysplasia” has been used in dogs with follicular dysplasia affecting black, brown, or blue hair coats (1-5). Black hair follicular dysplasia is heritable in mongrel dogs and may have a heritable basis in other breeds. Affected dogs are normal at birth but usually develop lesions within the first few weeks of life. Lesions consist of hypotrichosis, short, fractured hairs without lustre and scaliness. Color mutant alopecia has been reported in a variety of breeds of dogs and is best known in the blue Dober- man (4). It develops in dogs 3 months to 3 years of age (usually between 6 and 12 months), and is associated with coat color dilution of black to blue or red (brown) to fawn (6, 7). Rarely color mutant alopecia has been recognized in nondilute red or Correspondence and reprint requests to: Dr. Ann Hargis, DermatoDiagnostics, 17905 Talbot Road, Edmonds, WA 98026, U.S.A. Copyright European Society of Veterinary Dermatology and American College of Veterinary Derma- tology. black Dobermans (8). Color mutant alopecia has also been described in dogs with solid bi- and tri- color hair coats (9, 10). It has been reported that color mutant alopecia and black hair follicular dys- plasia can not be differentiated histologically (6). This paper reports a brief review of the literature of black hair follicular dysplasia and color mutant alopecia, and describes black hair follicular dysplasia in four female Saluki pups, a breed in which this disorder has not been previously described. REVIEW OF LITERATURE Black and white (piebald) mongrel dogs have devel- oped hypotrichosis with a dull, dry, lustreless hair coat in black haired areas (1, 1 I). A similar disorder also has developed in mongrel dogs in brown haired and blue haired areas (5). Selmanowitz reported that the mongrel dogs were normal at birth and white hair remained normal in growth, texture, and lustre (I). In the first few weeks of life, however, slowed growth of the black haired regions was noted. In 2 litters of 15 pups, 12 were affected, all were black and white. Three solid white dogs were normal (2). Black haired areas, of the neck and head, and marginal zones 69