This retrospective study describes 68 alpacas with skin diseases investigated from 1997 through 2006 at Cornell University. During this time period, 40 of 715 (5.6%) alpacas presented to the university hospital had dermatological diseases. In addition, skin-biopsy specimens accounted for 86 of 353 (24.4%) of alpaca biopsy specimens submitted to the diagnostic laboratory, and of these 86 specimens, follow-up was available for 28 cases. The following diseases were most common: bacterial infections (22%); neoplasms, cysts and hamartomas (19%); presumed immunological disorders (12%); and ectoparasitisms (10%). Conditions described for the first time included intertrigo, collagen and hair follicle hamartomas, lymphoma, hybrid follicular cysts, melanocytoma, anagen defluxion, telogen defluxion, presumed insect-bite hypersensitivity, ichthyosis, and possible hereditary bilateral aural haematomas and chondritis. The results of the retrospective study are compared and contrasted with the results of a literature review.

A retrospective light-microscopic study was performed on 294 biopsy specimens of haired skin from cats with various feline inflammatory dermatoses and specimens from cats with normal skin. Conditions expected to frequently have apoptotic epidermal keratinocytes (AKs) (including erythema multiforme, systemic lupus erythematosus, thymoma-associated exfoliative dermatitis, solar dermatitis, and viral dermatopathies) were found to have significantly more AKs than other types of inflammatory dermatoses. Nevertheless, we found more than two AKs in many skin-biopsy specimens from inflammatory conditions not expected to have frequent AKs (especially those from ectoparasitic dermatoses). Only a single AK was found in 1/33 cats with normal skin.