Histological and Trichographic Differences Between Coat Types in Non-Alopecic Pomeranians and Those With Alopecia X

February 2026 in “ Veterinary Dermatology ”

Ilse van Hensbergen, Chiara Brachelente, Jaco J. van der Lugt, J. van den Broek, Annette van der Lee

Alopecia X histological differences trichographic differences

Studysummary This study found that Pomeranians with Alopecia X had fewer follicles per group, more fragile hair, and distinct hair cycle stages compared to non-alopecic Pomeranians, highlighting coat-type differences significant for diagnosing the condition.

Our plain-language summary. Not medical advice or a treatment recommendation. Consult a qualified healthcare professional before changing treatment. Full disclaimer

The study compared histological and trichographic characteristics among 72 Pomeranians, including 30 with Alopecia X (AX), 22 with woolly coats (W), and 20 with shiny coats (S). AX dogs exhibited fewer follicles per group (4.1) compared to W and S (both 5.1). The anagen stage was predominant in S (60.2%), while telogen was more common in W (39.4%) and AX (39.8%). AX dogs also showed higher frequencies of kenogen and atrophic groups, as well as increased hair fragility and trichorrhexis nodosa ratios. These findings highlight coat-type differences that are important for diagnosing AX in Pomeranians.

View this study on onlinelibrary.wiley.com →

Discuss this study in the Community →

Research cited in this study

9 / 9 results

research Evaluation of Phenotypic Risk Indicators for the Development of Alopecia X in Pomeranian Dogs in the Netherlands and Belgium

2 citations , January 2025 in “Veterinary Dermatology”

This study found that Pomeranian dogs with a woolly coat type and male dogs had a higher risk of developing Alopecia X in the Netherlands and Belgian regions studied.

research Hair Fragility (Trichorrhexis Nodosa) in Alopecic Pomeranian Dogs

1 citations , September 2024 in “Veterinary Dermatology”

In this study, clinicians are advised to perform trichography regularly on Pomeranians with HCA, as significant hair abnormalities, especially TN, may affect hair quality; further research is needed to understand the underlying mechanisms and treatment options.

Dermoscopic Findings and Comparison of Usefulness of Longitudinal Versus Transversal Sections in the Histological Diagnosis of Alopecia X

research Dermoscopic Findings and Comparison of Usefulness of Longitudinal Versus Transversal Sections in the Histological Diagnosis of Alopecia X

1 citations , October 2023 in “Veterinary Dermatology”

This study found that in Pomeranian dogs with alopecia X, dermoscopic evaluations can supplement diagnoses, and transverse skin biopsy sections better assess hair follicle density and identify growth arrest phases compared to longitudinal sections.

research Isolated Autosomal Recessive Woolly Hair/Hypotrichosis: Genetics, Pathogenesis, and Therapies

9 citations , May 2021 in “JEADV. Journal of the European Academy of Dermatology and Venereology/Journal of the European Academy of Dermatology and Venereology”

This study suggests that topical minoxidil may be a promising treatment for isolated autosomal recessive woolly hair due to LIPH mutations, although effective treatments are not yet established.

research Bald Thigh Syndrome in Sighthounds: Revisiting the Cause of a Well-Known Disease

5 citations , February 2019 in “PloS one”

This study found that structural defects in the hair shafts of sighthounds with bald thigh syndrome are related to a downregulation of genes and proteins essential for hair shaft formation.

research Novel Insights Into the Pathways Regulating the Canine Hair Cycle and Their Deregulation in Alopecia X

18 citations , October 2017 in “PLOS ONE”

This study found that in Pomeranians with Alopecia X, key genes in the Wnt and Shh signaling pathways and stem cell markers are downregulated, which may explain the absence of anagen hair follicles.

research Estradiol-Induced Alopecia in Five Dogs After Contact With a Transdermal Gel Used for the Treatment of Postmenopausal Symptoms in Women

10 citations , July 2015 in “Veterinary Dermatology”

This study found that noninflammatory alopecia in dogs can be caused by exposure to estradiol gel used by their owners for postmenopausal symptoms, with hair regrowth observed after minimizing exposure.

research Canine Noninflammatory Alopecia: A Comprehensive Evaluation of Common and Distinguishing Histological Characteristics

28 citations , May 2012 in “Veterinary Dermatology”

In this study, dogs with hair cycle disorders, especially those with alopecia X, showed a significant increase in the number of kenogen follicles, suggesting impaired induction of new hair growth phases.

research Epidermal Patterning and Induction of Different Hair Types During Mouse Embryonic Development

81 citations , September 2009 in “Birth defects research”

This review discusses the mechanisms behind hair patterning during mouse embryonic development and reports no new experimental findings.