Black-hair follicular dysplasia in a New Zealand Huntaway Dog.
METHODS
A 6-year-old intact male New Zealand Huntaway dog had slowly progressive alopecia that was first observed at 12 weeks of age.


RESULTS
Patchy alopecia was confined to the black-haired areas of the body, and was most evident on the head and dorsum of the body; tan-haired areas of skin appeared normal. Histological examination of black-haired skin revealed distended melanocytes and large aggregates of melanin within, and surrounding, the hair follicles and the epidermis. Macrophages distended with melanin were also visible within the peri-follicular and superficial dermis, and follicular lumina were often plugged by keratin that contained aggregates of melanin. The follicles were dysplastic and few hair shafts were visible emerging from follicular infundibula within the sections.


METHODS
The clinical and histological findings were consistent with black-hair follicular dysplasia (BHFD).


CONCLUSIONS
This is the first report of BHFD in a dog in New Zealand, and is the first report in a Huntaway. The most significant effect of BHFD is a predisposition to follicular plugging and secondary bacterial skin infections. Due to the hereditary nature of the follicular dysplasias, breeding from affected dogs should be discouraged. Histological examination of the skin is required to differentiate between the different follicular dysplasias as well as differentiating between follicular dysplasia and follicular atrophy due to endocrinopathy.
Munday
J S
JS
Department of Pathobiology, Institute of Veterinary, Animal, and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand. j.munday@massey.ac.nz
French
A F
AF
McKerchar
G R K
GR
D000505:Alopecia / Q000209:etiology / Q000473:pathology / Q000662:veterinary; D000818:Animals; D001947:Breeding; D004283:Dog Diseases / Q000235:genetics / Q000473:pathology*; D004285:Dogs; D006197:Hair / Q000473:pathology; D006200:Hair Color; D006201:Hair Diseases / Q000235:genetics / Q000473:pathology / Q000662:veterinary*; D018859:Hair Follicle / Q000473:pathology*; D008297:Male; D008543:Melanins; D009520:New Zealand
D008543:Melanins