Wyss F, Schumacher V, Wenker C, Hoby S, Gobeli S, Arnaud A, Engels M, Friess M, Lange C E, Stoffel M H, Robert N
Institute of Animal Pathology, University of Bern, Bern, Switzerland Clinic for Zoo Animals, Exotic Pets and Wildlife, University of Zurich, Zurich, Switzerland
Institute of Animal Pathology, University of Bern, Bern, Switzerland.
Vet Pathol. 2015 Nov;52(6):1235-42. doi: 10.1177/0300985814568359. Epub 2015 Jan 23.
Pododermatitis is frequent in captive flamingos worldwide, but little is known about the associated histopathologic lesions. Involvement of a papillomavirus or herpesvirus has been suspected. Histopathologic evaluation and viral assessment of biopsies from 19 live and 10 dead captive greater flamingos were performed. Selected samples were further examined by transmission electron microscopy and immunohistochemistry. Feet from 10 dead free-ranging greater flamingos were also evaluated. The histologic appearance of lesions of flamingos of increasing age was interpreted as the progression of pododermatitis. Mild histologic lesions were seen in a 3-week-old flamingo chick with no macroscopic lesions, and these were characterized by Micrococcus-like bacteria in the stratum corneum associated with exocytosis of heterophils. The inflammation associated with these bacteria may lead to further histologic changes: irregular columnar proliferations, papillary squirting, and dyskeratosis. In more chronic lesions, hydropic degeneration of keratinocytes, epidermal hyperplasia, and dyskeratosis were seen at the epidermis, as well as proliferation of new blood vessels and increased intercellular matrix in the dermis. Papillomavirus DNA was not identified in any of the samples, while herpesvirus DNA was seen only in a few cases; therefore, these viruses were not thought to be the cause of the lesions. Poor skin health through suboptimal husbandry may weaken the epidermal barrier and predispose the skin to invasion of Micrococcus-like bacteria. Histologic lesions were identified in very young flamingos with no macroscopic lesions; this is likely to be an early stage lesion that may progress to macroscopic lesions.
足部皮炎在全球圈养火烈鸟中很常见，但对其相关的组织病理学病变却知之甚少。有人怀疑乳头瘤病毒或疱疹病毒与之有关。对19只活体和10只死亡的圈养大火烈鸟的活检组织进行了组织病理学评估和病毒检测。对选定的样本进一步进行了透射电子显微镜检查和免疫组织化学检查。还对10只死亡的野生大火烈鸟的足部进行了评估。随着火烈鸟年龄增长，病变的组织学表现被解释为足部皮炎的进展。在一只3周龄的火烈鸟雏鸟身上发现了轻微的组织学病变，没有肉眼可见的病变，其特征是角质层中有类似微球菌的细菌，伴有嗜异性粒细胞的胞吐作用。与这些细菌相关的炎症可能会导致进一步的组织学变化：不规则的柱状增生、乳头样突出和角化异常。在更慢性的病变中，表皮可见角质形成细胞的水样变性、表皮增生和角化异常，真皮中可见新血管增生和细胞间基质增加。在任何样本中均未鉴定出乳头瘤病毒DNA，仅在少数病例中发现了疱疹病毒DNA；因此，这些病毒不被认为是病变的原因。饲养管理欠佳导致皮肤健康状况不佳，可能会削弱表皮屏障，使皮肤易受类似微球菌的细菌侵袭。在没有肉眼可见病变的非常年幼的火烈鸟身上发现了组织学病变；这很可能是一个可能发展为肉眼可见病变的早期病变。
