A 3-year-old Standardbred trotting gelding presented to the Atlantic Veterinary College for diagnostic work-up of poor performance and abnormal respiratory noise during exercise. Physical examination was unremarkable, and no significant findings were identified on standing endoscopic examination of the upper respiratory tract. Treadmill endoscopy was utilised for dynamic evaluation of the upper respiratory tract; a diagnosis of epiglottic retroversion was confirmed. The owner requested euthanasia of the gelding, and a post-mortem evaluation was completed. Despite thorough gross and histological examination of the head and neck on post-mortem examination, no evidence was identified to support the postulated aetiologies for epiglottic retroversion currently found in the literature. This case represents the first reported findings from a post-mortem examination of a horse with epiglottic retroversion.

中文翻译：

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由于标准种猪蹄会厌后倾导致性能不佳

一头 3 岁的 Standardbred 小跑骟马被送到大西洋兽医学院进行运动时表现不佳和异常呼吸噪音的诊断检查。体格检查无明显异常，上呼吸道站立内镜检查未发现明显异常。跑步机内窥镜用于上呼吸道动态评估；确诊会厌后倾。主人要求对阉马进行安乐死，并完成了验尸评估。尽管在尸检中对头部和颈部进行了彻底的大体和组织学检查，但没有发现证据支持目前在文献中发现的会厌后倾的假设病因。