Fatal infection by Cyathostoma (Cyathostoma) phenisci (Nematoda: Syngamidae), was identified in 2 of 52 brown boobies (Sula leucogaster) collected on beaches in the state of Rio de Janeiro, Brazil, and admitted to the veterinary clinic for rehabilitation. Both infected birds were in poor physical condition, with atrophied pectoral muscles, and died soon after starting treatment. The parasitological and pathological examination of the carcasses revealed the presence of C. (C.) phenisci in the trachea, resulting in tracheitis, as well as severe parasitic granulomatous bronchopneumonia caused by eggs deposited in the lungs. In our opinion, these serious pathological changes were the primary cause of chronic respiratory illness. This is the first description of fatal cyathostomiasis in a fish-eating avian host caused by infection by a member of the subgenus Cyathostoma (Cyathostoma). Therefore, it is reasonable to consider C. (C.) phenisci to be a real threat to a wide range of their definitive hosts, and cyathostomiasis should be considered in the differential diagnosis for fish-eating marine birds, even in cases without respiratory signs. This is also the first record of the genus Cyathostoma in Brazil.

中文翻译：

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巴西Brown Booby（Sula leucogaster）致命性胞毒症的病因：病原鉴定及其对管理的意义。

在巴西里约热内卢州的海滩上收集到的52个棕色ob鸟中，有2个发现了由Cyathostoma phenisci（线虫：Syngamidae）引起的致命感染，并送进兽医诊所进行康复。两只受感染的鸟类身体状况不佳，胸肌萎缩，开始治疗后很快死亡。屠体的寄生虫学和病理学检查显示，气管中存在梭状芽孢杆菌，导致气管炎，以及由沉积在肺部的卵引起的严重的寄生性肉芽肿性支气管肺炎。我们认为，这些严重的病理变化是慢性呼吸系统疾病的主要原因。这是对食鱼鸟类寄主中致命性卵母细胞减少症的首次描述，该病是由Cyathostoma亚属（Cyathostoma）感染引起的。因此，有理由认为C.（C.）phenisci是对其广泛定殖宿主的真正威胁，并且在以鱼类为食的海鸟的鉴别诊断中应考虑到胞吞卵母虫病，即使在没有呼吸道症状的情况下也是如此。 。这也是巴西Cyhosthostoma属的第一个记录。