Study details rare hypotrichosis in deer and raccoons

A newly published brief report in the Journal of Veterinary Diagnostic Investigation expands the record of noninflammatory hypotrichosis in eastern U.S. wildlife, documenting affected white-tailed deer and raccoons rather than domestic species alone. The case series includes six animals with follicular dysplasia, two wild adult male raccoons and four wild yearling or adult white-tailed deer, plus a captive-reared stillborn male white-tailed deer with ectodermal dysplasia. The article was first published online June 1, 2026. (journals.sagepub.com)

The report lands in a niche but clinically important area of wildlife pathology. Hypotrichosis refers to reduced or absent normal hair growth and can appear in hereditary, congenital, or dysplastic forms. In white-tailed deer, published literature has been sparse: a 2004 Journal of Wildlife Diseases case described congenital hypotrichosis in a South Dakota fawn, and a 2023 report in JVDI described follicular dysplasia and hair loss in two wild deer in Wisconsin, where the syndrome had reportedly circulated informally as “toothpaste hair disease.” (pubmed.ncbi.nlm.nih.gov)

That background matters because alopecia in free-ranging wildlife usually triggers a much more familiar workup. State wildlife guidance for deer still centers on seasonal molt, lice, mange, and dermatophilosis as the leading explanations for patchy or generalized hair loss. Those conditions can bring inflammation, pruritus, crusting, secondary infection, or management concerns around congregation at feeding sites. Against that backdrop, the new paper helps define a subset of cases in which hair loss reflects follicular or ectodermal developmental abnormalities rather than an active infectious or parasitic process. (www11.maine.gov)

Additional context from the Southeastern Cooperative Wildlife Disease Study, whose investigators are among the paper’s authors, suggests these cases have been accumulating quietly for years. In its Fall 2024 newsletter, SCWDS described a behaviorally normal but completely hairless raccoon from Virginia with no ectoparasites detected and negative testing for canine distemper virus and rabies virus. The same issue also described an almost completely hairless white-tailed deer from North Carolina and a severely malformed stillborn deer fawn from the University of Georgia Whitehall Deer Research Facility. SCWDS wrote that it had seen “a handful of cases” in white-tailed deer and one case in a raccoon over the years, foreshadowing the more formal case compilation now published in JVDI. (vet.uga.edu)

The key diagnostic point is the paper’s emphasis on noninflammatory hypotrichosis. That distinction helps separate these cases from mange and other inflammatory dermatoses that dominate field suspicion when a deer or raccoon appears bald. Earlier deer reports described histologic changes such as distorted follicles, dilated infundibula, abnormal hair shafts, or follicles that were empty or filled with keratin debris, findings more consistent with follicular dysplasia or congenital hypotrichosis than with a transmissible ectoparasitic disease. In the stillborn fawn literature and the SCWDS case material, hypotrichosis also appears capable of occurring alongside broader developmental defects, including craniofacial abnormalities and cleft palate in severe forms. (journals.sagepub.com)

Public expert reaction appears limited so far, which is not unusual for a narrowly focused pathology brief report. Still, the institutional context is notable: several authors are affiliated with the University of Georgia and SCWDS, a major wildlife disease diagnostic and surveillance center in the Southeast, lending weight to the observation that these are real but likely underrecognized lesions rather than one-off curiosities. Based on the published and newsletter material, it’s reasonable to infer that diagnosticians are formalizing patterns they have seen intermittently in submissions, especially in deer. (vet.uga.edu)

Why it matters: For veterinary professionals, especially diagnosticians, wildlife veterinarians, pathologists, and rehab-linked clinicians fielding public reports of “mange” in deer or raccoons, this paper sharpens the differential diagnosis. Gross alopecia in wildlife can quickly raise concern about contagious disease, zoonotic risk, or population-level health threats. But if some cases are instead congenital or dysplastic hypotrichosis, the implications for case management, communications, and surveillance change. Histopathology, skin scraping, and targeted infectious disease testing remain essential for ruling out common causes before concluding a noninflammatory follicular disorder is present. That’s especially relevant when agencies are advising hunters, rehabilitators, or pet parents who may encounter affected wildlife near homes or feeding areas. (www11.maine.gov)

What to watch: The next step is whether additional case aggregation leads to genetic investigation, clearer prevalence estimates, or practical diagnostic guidance on when bald deer and raccoons should be worked up for hypotrichosis rather than presumed parasitic or infectious skin disease. (journals.sagepub.com)