Fischer Dominik, Van Waeyenberghe Lieven, Failing Klaus, Martel An, Lierz Michael
a Clinic for Birds, Reptiles, Amphibians and Fish , Justus Liebig University Giessen , Giessen , Germany.
b Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium.
Avian Pathol. 2018 Feb;47(1):33-46. doi: 10.1080/03079457.2017.1360470. Epub 2017 Sep 1.
Aspergillosis is a common and life-threatening respiratory disease in raptors with acute and chronic courses. Among raptors, gyrfalcons (Falco rusticolus) and their hybrids are often declared to be highly susceptible with juvenile individuals being the most susceptible. However, species- and age-specific experimental studies are lacking and minimal infective doses (IDs) for Aspergillus spp. conidia are unknown.Therefore, 8-week-old, healthy gyr-hybrid falcons (F. rusticolus X F. cherrug) (N = 18) were experimentally infected with Aspergillus fumigatus using a single intratracheal inoculation with varying dosages of conidia (10 to 10 conidia). Over 28 days, clinical signs were monitored as well as haematological and serological parameters. Following euthanasia, necropsy, histopathology, bacteriology, and mycology were performed. Re-isolated fungi were compared to the inoculum using microsatellite length polymorphisms. During the trial, clinical signs and dyspnoea correlated significantly with the ID. Necropsy revealed fungal lesions in the upper and lower airways of 10/18 inoculated falcons, but not in the control birds. In 9/18 inoculated falcons, fungal granulomas were confirmed in histopathology and A. fumigatus was re-isolated from these granulomas. Except one nasal isolate all re-isolated fungal strains were identical to the inoculum strain. Based on mycology and histopathology a minimal ID of 50% was calculated to be MID = 10 for a single tracheal inoculation of A. fumigatus conidia. This study demonstrates for the first time that a single exposure is able to cause acute aspergillosis in juvenile falcons.
曲霉病是猛禽中一种常见且危及生命的呼吸道疾病，有急性和慢性病程。在猛禽中，矛隼（矛隼）及其杂交种通常被认为高度易感，幼鸟最为易感。然而，缺乏针对特定物种和年龄的实验研究，曲霉菌分生孢子的最小感染剂量（IDs）也未知。因此，对18只8周龄健康的矛隼杂交种（矛隼×草原雕）进行实验性烟曲霉感染，通过气管内单次接种不同剂量的分生孢子（10 至 10 个分生孢子）。在28天内，监测临床症状以及血液学和血清学参数。安乐死后，进行尸检、组织病理学、细菌学和真菌学检查。使用微卫星长度多态性将重新分离的真菌与接种物进行比较。在试验期间，临床症状和呼吸困难与感染剂量显著相关。尸检发现10/18只接种的猎鹰上、下呼吸道有真菌病变，而对照鸟没有。在9/18只接种的猎鹰中，组织病理学证实有真菌肉芽肿，并且从这些肉芽肿中重新分离出烟曲霉。除了一株鼻腔分离株外，所有重新分离的真菌菌株都与接种菌株相同。根据真菌学和组织病理学计算出，气管内单次接种烟曲霉分生孢子的最小感染剂量为50%时，半数感染剂量（MID）=10。这项研究首次证明单次暴露能够在幼隼中引起急性曲霉病。
