Clinical, Histopathological and Epidemiological Features of Dorsal Melanotrichia of Poodles and Poodle Crosses.

Abstract

BACKGROUND: Poodles and poodle cross-breds develop a poorly described dorsal truncal hair coat condition informally called "doodle dysplasia". HYPOTHESIS/OBJECTIVE: To characterise the clinical, histopathological and epidemiological features of dorsal melanotrichia in poodles and poodle crosses. ANIMALS: Twenty-nine privately-owned poodles and poodle cross-breds with an unidentified cause for dorsal melanotrichia in the United States. MATERIALS AND METHODS: Retrospective and prospective case recruitment from private/academic dermatology and general practices, and involved record review, owner questionnaire, and dermatohistopathological analysis between 2019 and 2024. Inclusion criteria were poodles and poodle cross-breds with coat colour changes restricted to the dorsum, with or without other concurrent dermatological lesions or systemic signs. RESULTS: The average age of onset was 4 years. Summer was the most commonly reported season of onset (46% dogs), and recent grooming was noted in 57% of dogs with the information available. The most common pattern and distribution were serpiginous in 67% of dogs, and dorsal thorax and lumbar in 39% of dogs. Additional changes were alopecia and alteration of texture. Of those dogs with resolution, 71% had recurrence of coat colour and texture alterations 12 months or 24 months later. Histopathological changes were overall mild, with the most common being outer root sheath apoptosis and altered pigmentation in follicles, without strong evidence to support a dysplasia. CONCLUSION AND CLINICAL RELEVANCE: "Doodle dysplasia" is a condition with a possible seasonal and/or environmental component. Given the lack of clear evidence for dysplasia, we propose a new name: dorsal melanotrichia of poodles and poodle crosses.