Abstract：
American pikas (Ochotona princeps) are small lagomorphs that live in mountainous talus areas of western North America. Studies on the histopathology of American pikas are limited. We summarize here the clinical histories, and gross and histologic findings of 12 American pikas, including 9 captive (wild-caught) and 3 wild animals. Death was often attributed to stress (transport, handling, anesthesia) with few-to-no premonitory clinical signs. Infection was the cause of death in 2 cases: 1 had bacterial pyogranulomatous dermatitis, cellulitis, and lymphadenitis with sepsis; the other case had oomycete-induced necrotizing colitis. Incidental parasitic infections included sarcocystosis, nematodosis (oxyurids), and ectoparasitism. Most animals with adequate nutritional status had periportal hepatic lipidosis; this finding was absent in all animals with adipose atrophy, and it is possible that periportal hepatic lipidosis is non-pathologic in American pikas. Three cases had myocardial necrosis that was considered the cause of death; the cause of necrosis was not determined, but it may have been caused by stress or vitamin E-selenium deficiency. Esophageal hyperkeratosis was noted in animals with a history of anorexia and negative energy balance; accumulation of esophageal keratin can result from lack of mucosal abrasion by ingesta. Several histologic findings that are likely normal in American pikas include splenic extramedullary hematopoiesis, thymic tissue in adults, and Clostridium sp. in the enteric lumen.
摘要：
美国pikas（Ochotonaprinceps）是生活在北美西部多山的距骨地区的小lagomorphs。美国鼠兔的组织病理学研究有限。我们在这里总结临床病史，以及12只美国鼠兔的大体和组织学发现，包括9只圈养（野生捕获）和3只野生动物。死亡通常归因于压力(运输，处理,麻醉）几乎没有先兆临床体征。感染是2例患者的死亡原因：1例细菌性脓性肉芽肿性皮炎，蜂窝织炎,和淋巴结炎伴脓毒症；另一例有卵菌诱导的坏死性结肠炎。偶发寄生虫感染包括肌囊炎，线虫病（氧化），和外寄生症。大多数具有足够营养状态的动物具有门静脉周围肝脂沉积;这一发现在所有具有脂肪萎缩的动物中都不存在。在美国鼠兔中，门静脉周围肝脂沉着可能是非病理性的。3例心肌坏死被认为是死亡原因；坏死原因未确定，但它可能是由压力或维生素E-硒缺乏引起的。在有厌食症和负能量平衡病史的动物中发现食道角化过度；食道角蛋白的积累可能是由于食道缺乏粘膜磨损所致。美国鼠兔的几种可能正常的组织学发现包括脾髓外造血，成人胸腺组织，和梭菌属sp.在肠腔里.
