Journal of fish diseases最新文献

{"title":"Susceptibility of Non-Tuberculous Mycobacteria Biofilm to Common Disinfectants in Aquaculture Systems.","authors":"Claudio Murgia, Zeinab Yazdi, Esteban Soto","doi":"10.1111/jfd.14091","DOIUrl":"https://doi.org/10.1111/jfd.14091","url":null,"abstract":"<p><p>Mycobacteriosis is a common and persistent bacterial disease affecting cultured, wild and pet fish. The disease can be caused by various Mycobacterium spp. Currently, depopulation and disinfection are the main recommended measures for containing disease outbreaks, as no vaccines are commercially available, and only a few reports of successful antimicrobial therapies have been made. While disinfectant susceptibility studies have been conducted on planktonic forms of some non-tuberculous mycobacteria (NTM) affecting fish, biofilm-related research remains limited. In this study, biofilm formation of Mycobacterium chelonae, Mycobacterium salmoniphilum, Mycobacterium arcueilense and Mycobacterium marinum isolates recovered from diseased fish were initially evaluated using the minimal biofilm eradication concentration (MBEC) assay system. All Mycobacterium spp. were able to form biofilms within a 2-week period when incubated at 25°C, but M. chelonae, M. salmoniphilum and M. arcueilense produced a faster and greater biofilm than M. marinum. To investigate the susceptibility of mycobacterial biofilms to common disinfectants, mature biofilms were divided into six treatment groups based on disinfectant type and exposure time: povidone-iodine (50 mg L^-1 free iodine) and bleach (200 mg L^-1 free chlorine) were applied for 30 min each; hydrogen peroxide (3% H₂O₂) and Virkon Aquatic (10 g L^-1) were applied for 15 min each; and 70% ethanol was tested at both 15 and 30 min. Results demonstrated variable susceptibility among species. M. marinum was susceptible to all disinfectants, while M. arcueilense was susceptible to bleach, povidone-iodine and 70% ethanol (30-min exposure). None of the tested disinfectants at recommended doses effectively eradicated M. chelonae or M. salmoniphilum biofilms. These findings underscore species-specific differences in biofilm formation and resistance, emphasising the critical need for robust disinfection protocols in aquaculture settings to prevent mycobacteriosis transmission. Further research is essential to understand the mechanisms underlying disinfectant resistance among NTMs, optimise disinfection strategies and ensure the health and biosecurity of aquaculture facilities.</p>","PeriodicalId":15849,"journal":{"name":"Journal of fish diseases","volume":" ","pages":"e14091"},"PeriodicalIF":2.2,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143374341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Establishment and Application of a Rapid Detection Method of Cyprinid Herpesvirus 2 (CyHV-2) in Aquacultural Waters by Using a Novel One-Pot RAA-CRISPR/Cas12a Combined With Fe-Iron Flocculation Technology.","authors":"Zewei Hou, Zhaoyang Ding, Ye Zhang, Binghui Pang, Lang Gui, Ying Liu, Liqun Lu, Patarida Roengjitd, Hao Wang","doi":"10.1111/jfd.14089","DOIUrl":"https://doi.org/10.1111/jfd.14089","url":null,"abstract":"<p><p>Cyprinid herpesvirus 2 (CyHV-2) poses a substantial global threat to goldfish (Carassius auratus) and crucian carp (Carassius carassius). Despite the development of several sensitive molecular diagnostic techniques, there is an ongoing demand for alternative visualisation platforms to streamline the workflow, enhance safety profiles, and improve accessibility for end-users. In this study, we have integrated recombinase-aided amplification (RAA) technology with the CRISPR/Cas12a system to establish a rapid diagnostic system for CyHV-2, termed one-pot RAA-CRISPR/Cas12a. This method enables the results of detection within 60 min. The RAA-CRISPR/Cas12a platform is capable of detecting as few as 10 copies of CyHV-2 per reaction cycle without exhibiting cross-reactivity with other pathogens. The positive detection rate in clinical samples exceeds that of conventional PCR approaches, underscoring its high precision. Furthermore, the method could be used in conjunction with iron flocculation for the concentration and detection of viruses within aquaculture settings. This approach minimises the dissection of aquatic organisms, thereby maximising animal welfare and bolstering detection efficiency. Collectively, our findings validate the RAA-CRISPR/Cas12a method as a robust, specific, confirmatory, user-friendly and promising approach for on-site diagnosis of CyHV-2.</p>","PeriodicalId":15849,"journal":{"name":"Journal of fish diseases","volume":" ","pages":"e14089"},"PeriodicalIF":2.2,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143189422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Attenuating Vibrio harveyi Virulence Through Quorum Sensing Interference Using Piperine: An In Vitro and In Silico Approach.","authors":"Stephen Kyle C Arcan, Pattanan Yatip, Bamroong Munyoo, Mary Beth B Maningas, Chumporn Soowannayan, John Paul Matthew D Guzman","doi":"10.1111/jfd.14094","DOIUrl":"https://doi.org/10.1111/jfd.14094","url":null,"abstract":"<p><p>Aquaculture diseases caused by pathogens such as Vibrio spp., amplified by the emergence of antibiotic resistance, threaten the aquaculture industry. Due to its critical role in regulating the expression of genes related to antibiotic resistance and virulence, quorum sensing (QS) was proved to be an ideal target in disease control. In this study, we investigated the effects of the alkaloid piperine on the QS system of a fish pathogenic Vibrio harveyi strain. In vitro assays showed that piperine inhibits biofilm formation of V. harveyi without affecting their growth. Moreover, piperine specifically reduced QS activity in V. harveyi, as evident in the inhibition of biofilm and bioluminescence, likely through the AI-2 pathway. Molecular docking simulations showed significant binding energies between piperine and QS proteins-LuxP, LuxQ, LuxR and LuxS-revealing competitive inhibitory effects against LuxP, LuxR, and LuxS, and non-competitive interactions with LuxQ. This study demonstrated the effects of piperine against V. harveyi and elucidated its mechanism of action against V. harveyi QS, implying its potential application in aquaculture systems.</p>","PeriodicalId":15849,"journal":{"name":"Journal of fish diseases","volume":" ","pages":"e14094"},"PeriodicalIF":2.2,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143189419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Outbreak of Cryptocaryon irritans in Aquarium Quarantine-New Variations of an Old Theme.","authors":"Daniela Denk, Shane Boylan, Frank T Just, Matteo Sommer, Elsburgh O Clarke","doi":"10.1111/jfd.14084","DOIUrl":"https://doi.org/10.1111/jfd.14084","url":null,"abstract":"<p><p>An outbreak of Cryptocaryon irritans (Ci) occurred during the quarantine of marine teleost fish at a large aquarium facility, leading to 457 mortalities across 16 species. This study investigates the outbreak through a retrospective analysis of clinical and pathological findings, emphasising the role of detailed pathology in outbreak characterisation. Lesion diversity, host-specific susceptibility and mortality rates were examined alongside molecular diagnostics to confirm Ci presence. Key findings include significant differences in susceptibility and pathological presentations among fish families, with Chaetodontidae and Acanthuridae exhibiting severe gill and skin pathology, whereas Labridae and Scaridae showed enhanced parasite clearance associated with mucus production. A variety of treatment modalities were used, including formalin bath, Leteux-Meyer mixture and chloroquine, with variable treatment responses and species-specific drug sensitivities. Molecular analysis confirmed Ci with high sequence identity to isolates from the Red Sea and East Asia but highlighted primer limitations for frozen samples. This study outlines the challenges of managing a Ci outbreak in quarantine under unprecedented environmental conditions, underscores the importance of species-specific management strategies and provides detailed insights into host-pathogen interactions and treatment responses.</p>","PeriodicalId":15849,"journal":{"name":"Journal of fish diseases","volume":" ","pages":"e14084"},"PeriodicalIF":2.2,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143189415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overexpression of miR-155 Modulates Interferon Response and Inhibits Viral Replication of IHNV and IPNV in EPC Cells.","authors":"Najib Abdellaoui, Ik-Jun Park, Subin Choi, Minji Kim, Min Sun Kim","doi":"10.1111/jfd.14092","DOIUrl":"https://doi.org/10.1111/jfd.14092","url":null,"abstract":"<p><p>Infections caused by RNA viruses, including infectious haematopoietic necrosis virus (IHNV) and infectious pancreatic necrosis virus (IPNV), result in substantial economic losses in the aquaculture industry. MicroRNAs (miRNAs), particularly miR-155, play crucial roles in regulating host immune responses and viral infections. In this study, we investigated the overexpression effect of miR-155 in Epithelioma papulosum cyprini (EPC) cells infected with IHNV and IPNV and analysed the mechanisms underlying these antiviral activities. EPC cells were transfected with miR-155 at 40 pmol and then infected with IHNV or IPNV at an MOI of 0.01. The cytopathogenic effect (CPE) was observed for 5 days post-infection. The cells transfected with miR-155 did not show any signs of CPE or exhibit any viral growth over time after infection with both viruses. Additionally, real-time qPCR of type I interferon-related immune genes (ISG15 and Mx1) showed upregulation at 0, 24, and 48 h.p.i in cells transfected with miR-155. At 48 h post-infection, the cells transfected with miR-155 did not show any bands of viral protein by western blot. Furthermore, the overexpression of miR-155 in EPC cells significantly enhanced the expression of interferon response genes by targeting BCL2 and CYLD and suppressed the viral replication through directly targeting viral genes, including the L gene of IHNV and the VP2 gene of IPNV. These findings elucidate the dual mechanism of miR-155's antiviral effect through immune modulation and direct viral gene targeting, offering insights for developing novel antiviral strategies in aquaculture.</p>","PeriodicalId":15849,"journal":{"name":"Journal of fish diseases","volume":" ","pages":"e14092"},"PeriodicalIF":2.2,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143189447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal Dynamics of Immune Response Signalling in Largemouth Bass (Micropterus salmoides) Infected With Largemouth Bass Virus.","authors":"Xin Chu, Jing Chen, Lingyun Lin, Jiayun Yao, Lei Huang, Mingyue Gao, Jinyu Shen, Xiaoyi Pan","doi":"10.1111/jfd.14086","DOIUrl":"https://doi.org/10.1111/jfd.14086","url":null,"abstract":"<p><p>The largemouth bass virus (LMBV) significantly impacts Chinese largemouth bass aquaculture. The molecular mechanisms regulating LMBV virulence and the gene responses stimulated in the host during infection remain unclear. This study investigates the transcriptional dynamics and signalling pathways activated during the immune response to LMBV by analysing the transcriptome of head kidney tissues at 1, 4, 7, and 28 days post-infection (dpi) using RNA sequencing. Histopathological and viral load analyses indicated early tissue disruption, followed by extensive recovery by 28 dpi. Analysis of differentially expressed genes (DEGs) and weighted gene co-expression network analysis (WGCNA), combined with Venn analysis of samples at 1, 4, and 7 dpi, identified significant and common genes. Early infection triggered robust innate immunity through activation of the RIG-I like receptor and cGAS-STING signalling pathways, which activated type I interferons (IFNs) and interferon-stimulated genes (ISGs). Later stages indicated activation of adaptive immune responses. Validation of randomly selected genes via RT-qPCR confirmed the RNA-seq results, showing consistent expression patterns. This comprehensive study offers new insights into the sustained innate and adaptive immune responses to LMBV.</p>","PeriodicalId":15849,"journal":{"name":"Journal of fish diseases","volume":" ","pages":"e14086"},"PeriodicalIF":2.2,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143189450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Classification of Post-Delousing Mortality in Farmed Atlantic Salmon: A Case Study of Standardised Causal Classification at Fish-Level.","authors":"Nanna K Ringstad, Marit Stormoen, Paul J Midtlyng, David Persson","doi":"10.1111/jfd.14087","DOIUrl":"https://doi.org/10.1111/jfd.14087","url":null,"abstract":"<p><p>The study investigated cause-specific, fish-level mortality of farmed Atlantic salmon following mechanical delousing. We visited three populations at two marine sites belonging to one company at four different time points, from 1 day before to 13 days after the mechanical delousing. A total of 453 dead fish were collected and necropsied during the four visits. The underlying mortality cause was determined by macroscopic pathology in fish that died peracutely, acutely and subacutely after the procedure. The macroscopic pathological changes were recorded, and a cause of death was assigned to each fish by applying a uniform code system to classify mortality and losses in farmed Atlantic salmon. The findings revealed that mechanical delousing procedures can lead to mortality and pathological changes up to 13 days after the procedure. We identified cerebral haemorrhages in approximately 25% of the necropsied fish that died peracutely. Comparing the cause-specific mortality assignments at necropsy to daily mortality recordings by farmers showed that farmers assigned a smaller proportion of the fish to injury/trauma than the necropsy indicated. This implies that current practices for recording mortality causes by farmers after delousing may overlook the long-term negative effects of the procedure. Therefore, guidelines for farmers to more accurately record mortality causes following delousing are necessary to improve the value and precision of these records.</p>","PeriodicalId":15849,"journal":{"name":"Journal of fish diseases","volume":" ","pages":"e14087"},"PeriodicalIF":2.2,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143065949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Truncation-Enhanced Aptamer Binding Affinity and Its Potential as a Sensor for Macrobrachium rosenbergii Nodavirus Detection.","authors":"Norazli Ghadin, Syarul Nataqain Baharum, Nurul Hanun Ahmad Raston, Chen-Fei Low","doi":"10.1111/jfd.14093","DOIUrl":"https://doi.org/10.1111/jfd.14093","url":null,"abstract":"<p><p>White tail disease in Macrobrachium rosenbergii is caused by M. rosenbergii nodavirus (MrNV) infection, resulting in up to 100% mortality in larvae and post-larvae stages, severely impacting aquaculture production. Existing genome-based detection methods for MrNV are costly and time-consuming, highlighting the need for rapid and cost-effective diagnostic tests. This study evaluated the effects of truncating selected aptamer on its binding affinity to the MrNV capsid protein. The previously isolated and identified aptamer through magnetic-capture SELEX and Next Generation Sequencing demonstrated high binding affinity to the MrNV capsid protein. Truncation at the primer overhang was found to improve binding affinity, reducing the dissociation constant from 347 nM to 30.1 nM. The calculated limit of detection for the truncated aptamer decreased from 5.64 nM to 1.7 nM, while the limit of quantification decreased from 17.1 nM to 5.16 nM. These reductions indicate that the truncated aptamer has higher sensitivity compared to the full-length aptamer. In tests with MrNV-infected M. rosenbergii samples, both the enzyme-linked aptamer assay and the gold nanoparticle aptasensor assay showed consistent results when 0.5 μg of total protein lysate was used. This indicates that the prawn protein concentration interferes with the detection of the viral protein. These findings suggest the potential application of the truncated aptamer as a sensor in the development of a practical aptamer-based diagnostic kit. For instance, an aptamer-based lateral flow assay test kit could provide a user-friendly, cost-effective solution that eliminates the need for sophisticated instrumentation for diagnosis or data interpretation, making it ideal for detecting MrNV infection in M. rosenbergii aquaculture.</p>","PeriodicalId":15849,"journal":{"name":"Journal of fish diseases","volume":" ","pages":"e14093"},"PeriodicalIF":2.2,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143065950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hindcasting Farmed Salmon Mortality to Improve Future Health and Production Outcomes.","authors":"Benjamin R Knight, Eric A Treml, Zac Waddington, Ross Vennell, Kate S Hutson","doi":"10.1111/jfd.14058","DOIUrl":"https://doi.org/10.1111/jfd.14058","url":null,"abstract":"<p><p>Intracellular, free-floating and biofilm-forming bacterial pathogens have been implicated in summer mortality of farmed Chinook salmon, Oncorhynchus tshawytscha, in New Zealand. A mortality event in 2022 in the Pelorus Sound, Marlborough, was linked to high water temperatures (> 18°C), and bacterial skin disease associated with Piscirickettsia spp. (=Rickettsia-like organisms) and Tenacibaculum species. To understand the progression of infection and potential drivers of the mortality, simulation of the event was conducted using a networked susceptible, infectious and recovered (SIR) model. Parameter exploration shows that reconstruction of observed mortality rates across three affected farm sites was possible. The best SIR simulations identified plausible values for key drivers of disease, which are consistent with previously estimated disease parameter ranges for Piscirickettsia salmonis. Our modelling shows the 2022 Pelorus Sound event likely experienced spread of bacterial pathogens within healthy fish populations at salmon farm sites over a 10-week long incubation period, before elevated mortality was observed. We show evidence that vaccine use at one site likely prevented 10% higher mortality and that an alternative site for the vaccination could have further reduced mortalities. This result highlights the importance of future vaccine developments in aquaculture and the potential to improve vaccine efficacy through considered site selection.</p>","PeriodicalId":15849,"journal":{"name":"Journal of fish diseases","volume":" ","pages":"e14058"},"PeriodicalIF":2.2,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143046792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Associations Between Delousing Practices and Pasteurellosis in Farmed Atlantic Salmon.","authors":"Leif Christian Stige, Duncan J Colquhoun, Victor H S Oliveira","doi":"10.1111/jfd.14085","DOIUrl":"https://doi.org/10.1111/jfd.14085","url":null,"abstract":"<p><p>Infections with bacteria of the genus Pasteurella have increased in occurrence in Atlantic salmon (Salmo salar) farms in Norway since 2018. This increase coincides with increased use of non-medicinal treatments against the parasitic salmon louse, Lepeophtheirus salmonis, in the farms. Here, we analysed the statistical association between the use of non-medicinal delousing methods and pasteurellosis in salmon farming in western Norway, from 2018 to 2023. The analysed data covered 1161 production cycles from 356 farming localities, in which Pasteurella was detected in 166 production cycles from 115 localities. Results showed that in months with one or more thermal delousing using heated water to remove the lice, the odds for detection of Pasteurella were 2.5 times as high as in months with no delousing (95% credible interval, c.i.: 1.8, 3.6). In months with one or more mechanical delousing involving brushing or flushing, the odds were 1.8 times as high as in months with no delousing (c.i.: 1.04, 2.9). Delousing with freshwater was not associated with increased odds for Pasteurella. The odds for Pasteurella increased with increasing salmon weight and following a Pasteurella diagnosis in the previous production cycle. These results indicate that the use of thermal and mechanical delousing may play a role in maintaining the current pasteurellosis situation in western Norway, and that freshwater delousing may be a favourable alternative in this respect.</p>","PeriodicalId":15849,"journal":{"name":"Journal of fish diseases","volume":" ","pages":"e14085"},"PeriodicalIF":2.2,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143046732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}