Congenital follicular dysplasia in five related coatimundis (Nasua nasua).

We report a congenital follicular dysplasia in five coatis from four different litters of the same parents born between 1996 and 2001. These coatis were born apparently alopecic with the entire body covered by very short dark hairs, with secondary lichenification of the skin, crusting and scaling. The main histopathological feature consisted of premature cornification of the cortical cells of the hair shaft. Cells were already fully cornified below the Adamson's fringe, leading to a disorganized, fragmented and constricted hair shaft. Based on the history of the animals and the nature of the lesions, a genetic defect in hair shaft keratinization was suspected.