Evaluation of phenotypic risk indicators for the development of alopecia X (hair cycle arrest) in Pomeranian dogs in the Netherlands and Belgium.

Background: Alopecia X (AX) is a common noninflammatory alopecic condition of Pomeranian dogs with an unknown cause. While a genetic aetiology is suspected, no current tests can predict the development of this disorder or confirm the aetiology. Therefore, identifying potential risk indicators for the development of AX would be of value in this breed.

Objectives: This study aimed to identify risk indicators for AX in Pomeranians in the Netherlands and Belgium.

Materials and methods: A retrospective epidemiological study was conducted in the Netherlands and the Dutch-speaking parts of Belgium between March 2022 and August 2023, using an online survey of Pomeranian owners. Variables such as sex, birth season, neutering status, coat type, coat colour, grooming frequency and whether the dog experienced an 'ugly stage' of hair coat growth or not were recorded, along with the presence or absence of alopecia and the age of onset of the condition.

Results: Of 234 completed surveys, 211 were eligible for analysis. Statistical analysis with a Cox proportional-hazard model indicated that the risk of developing alopecia was greater for a woolly versus shiny coat and for males versus females.

Conclusions and clinical relevance: A woolly hair coat type and male sex were identified as risk indicators for developing AX in Pomeranian dogs in this study.