Zamparo Samuele, Orioles Massimo, Brocca Ginevra, Marroni Fabio, Castellano Ciro, Radovic Slobodanka, Mandrioli Luciana, Galeotti Marco, Verin Ranieri
Azienda Agricola Erede Rossi Silvio di Rossi Niccola, 62025, Sefro, MC, Italy.
Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, 33100, Udine, Italy.
Sci Rep. 2024 Aug 1;14(1):17791. doi: 10.1038/s41598-024-68287-w.
The generic term "Gill disease" refers to a wide range of disorders that affect the gills and severely impact salmonid aquaculture systems worldwide. In rainbow trout freshwater aquaculture, various etiological agents causing gill diseases have been described, particularly Flavobacterium and Amoeba species, but research studies suggest a more complex and multifactorial aetiology. Here, a cohort of rainbow trout affected by gill disease is monitored both through standard laboratory techniques and 16S rRNA Next-Generation Sequencing (NGS) analysis during a natural disease outbreak and subsequent antibiotic treatment with Oxytetracycline. NGS results show a clear clustering of the samples between pre- and post-treatment based on the microbial community of the gills. Interestingly, the three main pathogenic bacteria species in rainbow trout (Yersinia ruckeri, Flavobacterium psychrophilum, and Flavobacterium branchiophilum) appear to be weak descriptors of the diversity between pre-treatment and post-treatment groups. In this study, the dynamics of the gill microbiome during the outbreak and subsequent treatment are far more complex than previously reported in the literature, and environmental factors seem of the utmost importance in determining gill disease. These findings present a potential novel perspective on the diagnosis and management of gill diseases, showing the limitations of conventional laboratory methodologies in elucidating the complexity of this disease in rainbow trout. To the authors' knowledge, this work is the first to describe the microbiome of rainbow trout gills during a natural outbreak and subsequent antibiotic treatment. The results of this study suggest that NGS can play a critical role in the analysis and comprehension of gill pathology. Using NGS in future research is highly recommended to gain deeper insights into such diseases correlating gill's microbiome with other possible cofactors and establish strong prevention guidelines.
通用术语“鳃病”指的是一系列影响鳃的疾病，这些疾病严重影响着全球的鲑科鱼类养殖系统。在虹鳟淡水养殖中，已经描述了多种导致鳃病的病原体，特别是黄杆菌属和变形虫属，但研究表明其病因更为复杂且具有多因素性。在此，在一次自然疾病爆发以及随后用土霉素进行抗生素治疗期间，通过标准实验室技术和16S rRNA下一代测序（NGS）分析对一组受鳃病影响的虹鳟进行了监测。NGS结果显示，基于鳃的微生物群落，样本在治疗前和治疗后呈现出明显的聚类。有趣的是，虹鳟中的三种主要病原菌（鲁氏耶尔森菌、嗜冷黄杆菌和鳃黄杆菌）似乎并不能很好地描述治疗前和治疗后组之间的多样性。在本研究中，疾病爆发及后续治疗期间鳃微生物组的动态变化比以往文献报道的要复杂得多，环境因素在决定鳃病方面似乎至关重要。这些发现为鳃病的诊断和管理提供了一个潜在的新视角，显示了传统实验室方法在阐明虹鳟这种疾病的复杂性方面的局限性。据作者所知，这项工作是首次描述自然爆发及后续抗生素治疗期间虹鳟鳃的微生物组。本研究结果表明，NGS在鳃病理学的分析和理解中可以发挥关键作用。强烈建议在未来的研究中使用NGS，以更深入地了解此类将鳃微生物组与其他可能的辅助因素相关联的疾病，并制定强有力的预防指南。
