Abstract
Skin disease has been reported in captive Andean spectacled bears (Tremarctos ornatus) from the U.S., Europe, and South America. A web-based survey was undertaken to better characterize skin disease in the U.S. population. Based on survey results, females are more likely to develop skin conditions than males. Several females have been identified with similar clinical symptoms consisting of pruritus with progressive alopecia. Investigations are underway to determine common factors in these cases.
Discussion
Over the past 10 years a 21-year-old female Andean spectacled bear at the San Diego Zoo developed progressive alopecia and experienced episodes of pruritus and dermatitis. Thinning of the haircoat was initially observed and progressed to bilaterally symmetric alopecia over the caudal half of the body. Multiple diagnostic procedures revealed responses to certain allergens and presumed secondary bacterial/yeast dermatitis. It is unclear if these were the primary causes of the observed clinical signs. Equivocal response to therapy was observed with allergen desensitization, nutritional supplements, antihistamine, antimicrobial, and antifungal medications. Pruritus and skin lesions resolved with steroid therapy; however, alopecia persisted.
The authors became aware of other female spectacled bears in the United States and Europe with similar clinical conditions (Lydia Kolter, personal communication). Animal care staff and veterinarians from the San Diego Zoo and researchers from the San Diego Zoo’s Institute for Conservation Research developed an interest in further investigating this problem. A web-based survey was initiated to gather information on skin conditions in the SSP population and to evaluate if underlying risk factor(s) could be identified. The survey was divided into husbandry and veterinary sections.
The 2007 SSP studbook lists 67 (40.27) Andean spectacled bears in 35 institutions. The institutional representative for each institution was contacted via e-mail and asked to participate in the survey. In addition, veterinary staff in 27 of the 35 institutions were contacted via e-mail regarding the veterinary portion of the survey. Husbandry and veterinary data was collected from 15 and 13 institutions, respectively; however, both veterinary and husbandry information was available from only nine institutions. Technical difficulties with the on-line survey prevented some institutions from responding.
Evaluation of combined husbandry and veterinary data for 36 bears identified 4 of 19 (21%) males and 10 of 17 (59%) females had reported some type of skin problem. Ages of affected animals ranged from 3.5 to 19 years of age. One male had seasonal recurring non-symmetric alopecia, pruritus, moist pyoderma (“hot spots”), and bacterial dermatitis. Another male was noted to have a skin condition but without pruritus, alopecia, erosions, or exudate. Bilaterally symmetric alopecia was noted in a third male. The fourth male had two episodes of non-pruritic alopecia associated with skin exudate and a bacterial dermatitis.
Of the 10 females, seasonal pruritus, seasonal hot spots, and a chronic non-healing skin lesion were reported in three females. A fourth female had a single episode of pruritus, ocular inflammation, and alopecia that resolved with a change in bedding substrate. The remaining six had multiple recurrent episodes of pruritus and alopecia; alopecia was bilaterally symmetric and progressive over time. Periocular and conjunctival inflammation was seen in five of these six females. Five of the six bears had one or more episodes of bacterial dermatitis associated with clinical signs. Three had some seasonal component to episodes. Skin conditions occurred more frequently in females despite a population sex ratio skewed towards males. Of the spectrum of dermatologic conditions reported, 6 of 17 females (35%) exhibited chronic progressive bilaterally symmetric alopecia associated with pruritus.
Etiologies for the spectrum of diseases reported include infectious, endocrine, and/or allergic causes. Diagnostic testing included complete blood cell counts, serum chemistry panels, endocrine testing, cytologic examination of skin scrapings, histopathologic examination of skin biopsies, skin cultures, and allergen testing.
This survey indicated that skin disease has affected a large proportion of the captive U.S. spectacled bear population, similar to results of a survey conducted in Europe (Lydia Kolter, personal communication). Since our survey was conducted, the authors are aware of similar skin conditions in captive Andean spectacled bears in Venezuela (Andrés Bracho, personal communication) and Peru.1 The above information is primarily descriptive at this time with further analyses ongoing. A future goal is to make recommendations to the SSP for diagnostic screening of Andean spectacled bears in the U.S. population.
Acknowledgments
The authors wish to thank the following institutions for their participation in this survey: Gladys Porter Zoo, Cincinnati Zoo, Cleveland Metroparks Zoo, Granby Zoo, Houston Zoological Gardens, Montgomery Zoo, Philadelphia Zoological Gardens, Phoenix Zoo, Racine Zoo, Rolling Hills Wildlife Adventure, Salisbury Zoological Park, San Antonio Zoological Gardens, San Francisco Zoological Gardens, Sedgwick County Zoo, St. Louis Zoological Park, Tulsa Zoo and Living Museum, and Oglebay’s Good Children’s Zoo.
Literature Cited
1. Figueroa J, Stucchi M. Registro del Oso Andino en Cautiverio en el Perú y Algunos Alcances para su Mantenimiento. Asociación Ucumari, Lima, Perú. 2005.