Accessory tragus is a congenital malformation of part of the external ear, commonly reported in humans. Clinically, it is a benign, cutaneous mass located anywhere between the tragus of the ear and the angle of the mouth, along the migratory path of the first branchial arch. An accessory tragus was diagnosed in an otherwise healthy six-month-old male castrated American pit bull terrier that had a haired, pedunculated cutaneous mass on the left maxillary region from birth. Histologically, the mass was a polypoid extension of histologically normal haired skin with a central core of subcutaneous adipose tissue and well-differentiated elastic cartilage. To the authors’ knowledge, this is the first report of this lesion in a non-human species. Retrospective examination of records from 2008 to 2018 at the Washington Animal Disease Diagnostic Laboratory failed to identify any other case. As accessory tragus in humans is commonly linked with other congenital anomalies and syndromes, recognition of this lesion in animals may aid in early discovery of other congenital defects and inform adequate excision of the lesion to prevent chondrodermatitis.

耳屏小耳是外耳部分的先天性畸形，通常在人类中报道。在临床上，它是沿第一小弓的迁移路径位于耳朵的耳屏和嘴角之间的任意位置的良性皮肤肿块。在原本健康的六个月大的cast割的美国斗牛犬中诊断出了副耳屏，该from牛从出生起就在左上颌区域有头发，带蒂的皮肤块。从组织学上讲，该肿块是组织学正常的毛发皮肤的息肉状延伸，其皮下脂肪组织的中心核心和分化良好的弹性软骨。据作者所知，这是该病在非人类物种中的首次报道。在华盛顿动物疾病诊断实验室对2008年至2018年的记录进行的回顾性检查未能发现其他病例。由于人类副耳屏通常与其他先天性畸形和综合症有关，因此在动物中识别该病灶可能有助于及早发现其他先天性缺陷，并告知要充分切除病灶以预防软骨性皮炎。