Diseases of aquatic organisms最新文献

Comparative genomics of Photobacterium damselae from Penaeus (Marsupenaeus) japonicus: insights into pathogenicity and adaptation. 日本对虾（Marsupenaeus） damselae光杆菌的比较基因组学：致病性和适应性的见解。

IF 1.2 4区农林科学

Diseases of aquatic organisms Pub Date : 2026-10-08 DOI: 10.3354/dao03936

Wafaa Ragab, Satoshi Kawato, Jayasundara Mudiyanselage Sajani Nisansala Rathnapala, Reiko Nozaki, Ikuo Hirono

{"title":"Comparative genomics of Photobacterium damselae from Penaeus (Marsupenaeus) japonicus: insights into pathogenicity and adaptation.","authors":"Wafaa Ragab, Satoshi Kawato, Jayasundara Mudiyanselage Sajani Nisansala Rathnapala, Reiko Nozaki, Ikuo Hirono","doi":"10.3354/dao03936","DOIUrl":"https://doi.org/10.3354/dao03936","url":null,"abstract":"Photobacterium damselae subsp. damselae (PDD), a halophilic, Gram-negative bacterium of the family Vibrionaceae, infects a wide range of aquatic organisms. PDD isolates originating from fish have been characterized in detail, but much less is known about those infecting invertebrates. Currently, only 3 complete PDD genomes isolated from Kuruma shrimp Penaeus (Marsupenaeus) japonicus from Japan are publicly available, severely limiting comparative studies of host adaptation. To address this, we present complete, plasmid-resolved genome assemblies of 4 novel PDD strains (TUMSAT-PD1, -PD2, -PD3, and -PD4) isolated from diseased Kuruma shrimp across multiple prefectures in Japan. Phylogenomic analysis reveals that shrimp PDD strains are genetically heterogeneous and closely related to those infecting other aquatic organisms, suggesting that pathogenicity against shrimp arose independently in multiple PDD strains. While core virulence determinants are chromosomally encoded, we identified key plasmid-borne virulence factors that are likely to enhance the pathogenicity of PDD strains. Comparative analysis with 3 publicly available PDD genomes demonstrated both conserved core virulence determinants and strain-specific accessory genes, reflecting local adaptation and evolutionary diversification. Our findings provide the first geographically expanded genomic framework for Kuruma shrimp-associated PDD, integrating 4 novel Japanese isolates with the existing public genomes. This integrated data set demonstrates that PDD exhibits a generalist evolutionary strategy, capable of rapid adaptation to diverse hosts through conserved virulence machinery and mobile genetic elements. This work significantly expands the genomic basis for understanding PDD epidemiology and pathogenesis within aquaculture systems.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"168 ","pages":"1-17"},"PeriodicalIF":1.2,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149135455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Pathology of coral growth anomalies in the Maldives: insights from Acropora, Montipora, and Pachyseris. 马尔代夫珊瑚生长异常的病理学：来自Acropora、Montipora和Pachyseris的见解。

IF 1.2 4区农林科学

Diseases of aquatic organisms Pub Date : 2026-09-24 DOI: 10.3354/dao03934

Chiara Bises, Michelle M Dennis, Jacopo Gobbato, Greta S Aeby, Paolo Galli, Simone Montano

{"title":"Pathology of coral growth anomalies in the Maldives: insights from Acropora, Montipora, and Pachyseris.","authors":"Chiara Bises, Michelle M Dennis, Jacopo Gobbato, Greta S Aeby, Paolo Galli, Simone Montano","doi":"10.3354/dao03934","DOIUrl":"10.3354/dao03934","url":null,"abstract":"Coral growth anomalies (GAs) are chronic skeletal lesions that alter coral morphology and functionality, yet their etiology remains poorly understood, particularly in understudied regions such as the Maldives. This study provides the first comprehensive pathological description of 15 GAs from the Maldivian Archipelago across 3 coral genera, Acropora, Montipora, and Pachyseris, with the last still lacking a histopathological characterization to date. Despite varying gross morphologies (either bosselated, umbonate, nodular, or fimbriated masses), all lesions microscopically exhibited basal body wall hyperplasia corresponding to areas of lax, porous, and inconsistent skeletal architecture as observed by scanning electron microscopy. Common histological findings included calicoblast hypertrophy (74%), endosymbiont depletion in the surface body wall (60%) corresponding to grossly observed discoloration of the GA, absence of gonadal development (80%), and diffuse mucocyte hyperplasia (seen only in Pachyseris). Most GAs (60%) contained centrally located masses of organisms that corresponded to regions of skeletal cavitation observed on sub-gross examination. Organisms included fungi, algae, cyanobacteria, diatoms, and labyrinthulomycetes, which in 90% of cases were invading surrounding tissues, suggesting a role in pathogenesis. Additionally, some GAs had solitary endolithic sponges (26%) or degenerate sponge-like debris (13%) in gastrovascular cavities. These findings further suggest multifactorial etiologies for the lesions, reinforcing the complexity of GAs, the limitations of current diagnostic frameworks, and challenges to lesion nomenclature.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"167 ","pages":"1-20"},"PeriodicalIF":1.2,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149036958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Growth and sporulation differences of genetically distinct Saprolegnia parasitica strains in vitro. 不同遗传寄主菌的体外生长和产孢差异。

IF 1.2 4区农林科学

Diseases of aquatic organisms Pub Date : 2026-09-24 DOI: 10.3354/dao03935

Ossi Laurikainen, Jaakko Haverinen, Tiina Korkea-Aho, Matti Janhunen, Anssi Vainikka

{"title":"Growth and sporulation differences of genetically distinct Saprolegnia parasitica strains in vitro.","authors":"Ossi Laurikainen, Jaakko Haverinen, Tiina Korkea-Aho, Matti Janhunen, Anssi Vainikka","doi":"10.3354/dao03935","DOIUrl":"https://doi.org/10.3354/dao03935","url":null,"abstract":"Saprolegnia species are major oomycete pathogens of freshwater fishes, causing significant economic and ecological losses in aquaculture and wild populations. Most saprolegniosis disease outbreaks have been attributed to single or very few genetic clones, but potential differences among strains and the covariation of their virulence and transmission traits have remained largely unresolved. In this study, we investigated differences in laboratory growth and sporulation among 9 pathogenic S. parasitica isolates originating from infected salmonids from 6 aquaculture facilities and 1 wild waterbody across Finland. All isolates were assigned to distinct strains using either specific qPCR or by sequencing the internal transcribed spacer, species identification was confirmed and unified by genome reassembly, and phylogenetic analysis was performed to characterise genetic relationships among the strains. Hyphal growth, time to initiate spore production, spore numbers, and count of repeated zoospore emergence cycles were measured, and potential phenotypic associations among these functional measures were assessed. The strains formed 3 distinct clades with 7 out of the 9 strains clustering into clade I, whereas clades II and III were singletons. Phylogenetic clade, timepoint, and their interaction all significantly affected hyphal growth, indicating timepoint-dependent clade differences. Strains within clade I were faster to initiate sporulation and produced more spores than the singleton clades II and III. Associations between hyphal growth and sporulation metrics did not support trade-offs between transmission- and virulence-related traits; strains with fastest growth and sporulation produced the most spores.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"167 ","pages":"1-14"},"PeriodicalIF":1.2,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149036892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Chelonid alphaherpesvirus 5 qPCR of archived blood and skin samples underpredicts infections in juvenile green turtles Chelonia mydas. 龟类甲疱疹病毒5 qPCR对龟幼龟感染的预测不足。

IF 1.2 4区农林科学

Diseases of aquatic organisms Pub Date : 2026-08-27 DOI: 10.3354/dao03932

Jake R Kelley, Tamara Lee, Katherine R Martin, Leah T Rittenburg, Kate L Mansfield, Anna E Savage

{"title":"Chelonid alphaherpesvirus 5 qPCR of archived blood and skin samples underpredicts infections in juvenile green turtles Chelonia mydas.","authors":"Jake R Kelley, Tamara Lee, Katherine R Martin, Leah T Rittenburg, Kate L Mansfield, Anna E Savage","doi":"10.3354/dao03932","DOIUrl":"https://doi.org/10.3354/dao03932","url":null,"abstract":"Chelonid alphaherpesvirus 5 (ChHV5) is the putative pathogen of fibropapillomatosis, a tumor-forming sea turtle disease. Quantitative polymerase chain reaction (qPCR) techniques are commonly applied to evaluate the presence and quantity of ChHV5 in blood and tissue samples. However, samples can have little or no virus present despite coming from infected individuals. In addition, sample age and storage may further impact ChHV5 detection. This creates uncertainty in the interpretation of ChHV5 qPCR results for archived (>1 yr old) blood and skin because a negative sample does not imply an individual was free of ChHV5 infection, but rather that the sample itself was free of viable ChHV5 DNA. To assess the ability of qPCR to detect ChHV5 infections from archived samples, we tested blood, skin, and tumor samples collected from juvenile green turtles Chelonia mydas captured in the Indian River Lagoon, Florida, USA, between 1995 and 2018. Sample ages ranged from 1 to 24 yr old at the time of molecular analyses. We found very low overall prevalence of ChHV5 in blood (1.4% positive, n = 513) and skin (6.5% positive, n = 123) samples, and high prevalence in tumor samples (89.7% positive, n = 39). These results suggest that qPCR of archived blood and/or skin samples provides little inference on individual-level infection status.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"167 ","pages":"1-6"},"PeriodicalIF":1.2,"publicationDate":"2026-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148826077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stage-dependent efficacy of long double-stranded RNA administered after white spot syndrome virus infection in shrimp. 对虾感染白斑综合征病毒后给予长双链RNA的分期依赖性效果。

IF 1.2 4区农林科学

Diseases of aquatic organisms Pub Date : 2026-08-27 DOI: 10.3354/dao03933

Soon Joo Hong, Ki Hong Kim

{"title":"Stage-dependent efficacy of long double-stranded RNA administered after white spot syndrome virus infection in shrimp.","authors":"Soon Joo Hong, Ki Hong Kim","doi":"10.3354/dao03933","DOIUrl":"https://doi.org/10.3354/dao03933","url":null,"abstract":"White spot syndrome virus (WSSV) causes catastrophic losses in shrimp aquaculture, yet no antiviral interventions are available once infection has begun. In this study, we evaluated the stage-dependent efficacy of RNA interference (RNAi) by administering long double-stranded RNA (dsRNA) targeting the WSSV ribonucleotide reductase 2 (rr2) gene at defined time points following viral challenge in Penaeus vannamei. Delivery of dsRNA during the peri-infection period (0-12 h post-infection, hpi) resulted in near-complete protection, consistent with interference prior to extensive viral establishment. Importantly, administration during the early post-infection phase (24-48 hpi) significantly reduced mortality and viral loads, demonstrating that RNAi retains therapeutic relevance after viral replication has begun. In contrast, treatment during the late post-infection phase (72 hpi) provided only limited protection, indicating a sharp decline in efficacy once high viral burdens were established. Increasing dsRNA dosage enhanced viral suppression but did not proportionally improve survival, whereas higher viral challenge doses delayed rr2 transcript suppression and reduced therapeutic outcomes. Together, these results define a biologically constrained early post-infection therapeutic window for RNAi-based intervention against WSSV, determined by both infection stage and viral burden at the time of treatment. Although injection-based delivery limits immediate field application, this study provides a realistic framework for developing post-exposure RNAi strategies for disease management in shrimp aquaculture.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"167 ","pages":"1-10"},"PeriodicalIF":1.2,"publicationDate":"2026-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148826122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Whole plant disease severity is associated with reduced polyphenolic concentrations in lesioned but not green tissue in eelgrass Zostera marina. 全株疾病严重程度与大叶藻受损组织中多酚浓度降低有关，而与绿色组织中多酚浓度降低无关。

IF 1.2 4区农林科学

Diseases of aquatic organisms Pub Date : 2026-08-27 DOI: 10.3354/dao03930

Naomi A Murray, Katherine DuBois, John J Stachowicz

{"title":"Whole plant disease severity is associated with reduced polyphenolic concentrations in lesioned but not green tissue in eelgrass Zostera marina.","authors":"Naomi A Murray, Katherine DuBois, John J Stachowicz","doi":"10.3354/dao03930","DOIUrl":"https://doi.org/10.3354/dao03930","url":null,"abstract":"Plants possess an impressive range of chemical traits to defend themselves against pathogens. Describing and interpreting these traits can provide insights into plant resistance to infection and disease progression. To examine one potentially responsive chemical trait, we measured polyphenolic content of green and lesioned tissue from Labyrinthula-infected eelgrass shoots growing in both the field and a long-term common garden. Infection of eelgrass Zostera marina with wasting disease (Labyrinthula zosterae) leads to the formation of necrotic lesions on host tissue and is known to alter host photobiology and secondary metabolite production. It is common to quantify total polyphenolics as a potential measure of eelgrass defense against infection, yet there is no clear evidence that polyphenolics are a reliable indicator of host response or immunity. We found that polyphenolic concentrations in lesion tissue fell predictably as lesion cover increased, while polyphenolic concentrations in green tissue were more variable and increased only across large ranges of lesion cover. We hypothesize that while polyphenolic induction may be a part of the host plant response to L. zosterae infection, total polyphenolic concentrations in both green and lesioned tissue may also be influenced by genetic variability and localized metabolic processes. Further research is necessary to assess a causative relationship between plant defenses and disease severity in this system and may benefit from looking beyond phenolics.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"167 ","pages":"1-6"},"PeriodicalIF":1.2,"publicationDate":"2026-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148826175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dietary pineapple peel powder supplementation enhances resistance against Aeromonas veronii in Labeo rohita fingerlings. 日粮中添加菠萝皮粉可增强罗氏小龙虾鱼种对维罗氏气单胞菌的抵抗力。

IF 1.2 4区农林科学

Diseases of aquatic organisms Pub Date : 2026-08-13 DOI: 10.3354/dao03929

Chandan Debnath

{"title":"Dietary pineapple peel powder supplementation enhances resistance against Aeromonas veronii in Labeo rohita fingerlings.","authors":"Chandan Debnath","doi":"10.3354/dao03929","DOIUrl":"10.3354/dao03929","url":null,"abstract":"This study investigated the immunomodulatory effects of dietary pineapple peel powder (PPP) supplementation in Labeo rohita fingerlings (15.2 ± 0.3 g) through a 60 d feeding trial followed by a 15 d Aeromonas veronii infection challenge. Processing 1 kg of pineapple fruit generates approximately 30-35% waste, primarily peels, containing bioactive compounds including bromelain enzyme. Using a completely randomized design, 300 fingerlings were distributed into 5 treatment groups in triplicate: Control (0%), T1 (2%), T2 (4%), T3 (6%), and T4 (8%) PPP supplementation. Immunological, haematological, biochemical, and antioxidant parameters were assessed at 0, 15, 30, and 60 d, with bacterial challenge conducted on Day 61 and post-infection (PI) sampling at 7 and 15 d PI. Fish fed 6% PPP (T3) exhibited significantly enhanced immunological parameters, with serum lysozyme activity reaching 185.6 ± 8.4 unit ml-1 compared to 112.3 ± 5.7 unit ml-1 in control. Significant improvements occurred in haematological indices (red blood cells, white blood cells, hemoglobin, hematocrit), serum proteins (total protein, albumin, globulin), and antioxidant enzyme activities (superoxide dismutase, catalase, glutathione peroxidase). Following A. veronii challenge (1×107 CFU ml-1; 0.1 ml fish-1), T3 demonstrated the highest survival rate (82.5 ± 3.4%) compared to control (45.6 ± 2.7%). Growth performance also improved significantly, with specific growth rate (2.84 ± 0.12% vs. 2.15 ± 0.09% d-1) and feed conversion ratio (1.42 ± 0.06 vs. 1.85 ± 0.08) both enhanced in T3 compared to control. These results demonstrate that 6% PPP supplementation optimally enhances immunophysiological parameters, disease resistance, and growth performance in L. rohita, highlighting its potential as a natural immunostimulant in sustainable aquaculture health management.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"167 ","pages":"1-18"},"PeriodicalIF":1.2,"publicationDate":"2026-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148721307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Blood analytes in California sea lion Zalophus californianus pups: reference intervals and malnutrition effects, from admission to rehabilitation. 加利福尼亚海狮幼崽的血液分析：参考间隔和营养不良的影响，从入院到康复。

IF 1.2 4区农林科学

Diseases of aquatic organisms Pub Date : 2026-08-13 DOI: 10.3354/dao03931

Faye E Giebink, Alissa C Deming, Justin R Perrault, Malena Berndt, Sharon R Melin, Nicole I Stacy

{"title":"Blood analytes in California sea lion Zalophus californianus pups: reference intervals and malnutrition effects, from admission to rehabilitation.","authors":"Faye E Giebink, Alissa C Deming, Justin R Perrault, Malena Berndt, Sharon R Melin, Nicole I Stacy","doi":"10.3354/dao03931","DOIUrl":"10.3354/dao03931","url":null,"abstract":"Blood analyte data are limited for California sea lion Zalophus californianus pups despite frequent admission to rehabilitation facilities. The objectives of this study were to establish blood analyte reference intervals for rehabilitated California sea lion pups (n = 58) deemed clinically normal for release and for free-ranging California sea lion pups (n = 37) during routine health assessment on San Miguel Island, California, USA; to compare manual white blood cell (WBC) differentials to an in-house hematology analyzer (ProCyte Dx); and to evaluate paired blood analyte data of pups affected by malnutrition at time of intake compared to release and in comparison to free-ranging conspecifics. From 2020 to 2022, all stranded pups were thin or emaciated with various additional health concerns at admission (e.g. pneumonia, abscesses, ocular injuries). Average time in rehabilitation was 101 ± 27 d. Reference intervals were established for successfully rehabilitated and free-ranging pups. WBC differential counts evaluated by the analyzer compared to manual blood film review were inconsistent. Blood analytes of pups differed between intake and release, and with free-ranging conspecifics. These findings provide evidence for systemic inflammation, nutritional imbalances, and metabolic derangements in stranded malnourished pups and elucidate physiological changes undergone by growing pups during rehabilitation, particularly as they differ from free-ranging conspecifics. Moreover, the results herein underscore the importance of blood film review for obtaining accurate data for the establishment of reference intervals. These data aim to support clinical assessments of sea lion pups at intake and at release in context of other clinically relevant release criteria.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"167 ","pages":"1-27"},"PeriodicalIF":1.2,"publicationDate":"2026-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148721786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Causes of death in short-beaked common dolphins Delphinus delphis stranded in Cornwall, England (2018-2024), reveal the continued threat of bycatch. 被困在英格兰康沃尔郡（2018-2024）的短喙普通海豚的死亡原因揭示了副捕捞的持续威胁。

IF 1.2 4区农林科学

Diseases of aquatic organisms Pub Date : 2026-08-13 DOI: 10.3354/dao03937

J E F Barnett, H Chadwick, K Astley, N J Davison, R Deaville, B J Godley, A Hawtrey-Collier, G H Leeming, S K Macgregor, S K John, S E Nelms, S Trew, M E Wessels

{"title":"Causes of death in short-beaked common dolphins Delphinus delphis stranded in Cornwall, England (2018-2024), reveal the continued threat of bycatch.","authors":"J E F Barnett, H Chadwick, K Astley, N J Davison, R Deaville, B J Godley, A Hawtrey-Collier, G H Leeming, S K Macgregor, S K John, S E Nelms, S Trew, M E Wessels","doi":"10.3354/dao03937","DOIUrl":"10.3354/dao03937","url":null,"abstract":"The short-beaked common dolphin Delphinus delphis is the most frequently stranded cetacean species around the 700 km coastline of Cornwall, southwest England, with over 100 animals stranding each year. Between January 2018 and December 2024, 867 stranded common dolphins were reported, of which 175 (20%) individuals were necropsied. The most common cause of death was bycatch, accounting for 39% (n = 68; interannual range: 29-44%). Observed pathology and available fishing effort data suggest that smaller vessels engaged in static (and potentially drift net) fishing were the most probable cause of the majority of diagnosed bycatch mortality. Infectious disease was the probable cause of death in 25% of cases (n = 43), with severe parasitism being implicated in 32 of these cases. Live stranding of animals in relatively good health and nutritional status accounted for 10% (n = 17) of cases, where the only significant pathological changes found were lesions that could be attributed to the stranding event itself. Non-bycatch related trauma (n = 14) and starvation (n = 13) represented 8 and 7% of cases, respectively. Other causes of death included gastric impaction (n = 5), peritonitis (n = 3), intestinal impaction (n = 2), non-bycatch related asphyxia (n = 2) and gas embolism (n = 2). In 5 cases, the cause of death could not be established. Necropsies of common dolphins carried out in Cornwall make a substantial contribution to our knowledge of the threats faced by this species in UK waters and the wider region. This includes the continued impact of fisheries-related mortality, with Cornwall being the hotspot for bycatch of this species in the UK.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"167 ","pages":"1-23"},"PeriodicalIF":1.2,"publicationDate":"2026-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148720576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thyroid hormones and serum iodine in clinically normal versus chronically malnourished Florida manatees Trichechus manatus latirostris. 临床正常与慢性营养不良佛罗里达海牛的甲状腺激素和血清碘。

IF 1.2 4区农林科学

Diseases of aquatic organisms Pub Date : 2026-07-30 DOI: 10.3354/dao03928

Amber M Lum, Martine de Wit, Jorge A Hernandez, Sarah I Jacob, Stacy DiRocco, David Rotstein, Brittany Barbeau, Robert K Bonde, Nicole I Stacy

{"title":"Thyroid hormones and serum iodine in clinically normal versus chronically malnourished Florida manatees Trichechus manatus latirostris.","authors":"Amber M Lum, Martine de Wit, Jorge A Hernandez, Sarah I Jacob, Stacy DiRocco, David Rotstein, Brittany Barbeau, Robert K Bonde, Nicole I Stacy","doi":"10.3354/dao03928","DOIUrl":"https://doi.org/10.3354/dao03928","url":null,"abstract":"An unusual mortality event (UME) was declared from December 2020 to April 2022 after increased deaths of emaciated Florida (FL) manatees Trichechus manatus latirostris occurred in the Indian River Lagoon (FL, USA) following seagrass reduction. While thyroid hormones are known to fluctuate with fasting, stress, and disease in pinnipeds and cetaceans, investigations in sirenians are limited. Serum from clinically normal free-ranging FL manatees (n = 35) and individuals affected by the UME (n = 20) was analyzed via radioimmunoassay and chemiluminescent immunoassays for total triiodothyronine (TT3), total thyroxine (TT4), and free thyroxine (fT4) quantification after assay validation. Total iodine (TI) and inorganic iodine (INORG-I) were measured using inductively coupled plasma mass spectrometry; organic iodine (ORG-I) was calculated from these values. Reference intervals for TT3 and TT4 were generated for clinically normal manatees. There were no differences in TT3, TT4, TI, or INORG-I between groups. Body condition index weight difference expressed as a percentage of the population mean (BCI%) and fT4 were significantly lower in UME manatees, most consistent with chronic starvation. However, BCI% and fT4 were not significantly different between UME manatees who survived rehabilitation versus those who died, suggesting these are unreliable prognostic markers. Serum ORG-I was significantly higher in UME manatees. High thyroid tissue iodine in necropsied UME manatees (n = 6), associated with follicular cysts in a subset (n = 3), suggests a potential impact on thyroid gland metabolism. These data expand the current understanding of pathophysiological aspects of the UME due to chronic malnutrition and may help guide supportive care for FL manatees undergoing rehabilitation.","PeriodicalId":11252,"journal":{"name":"Diseases of aquatic organisms","volume":"167 ","pages":"1-12"},"PeriodicalIF":1.2,"publicationDate":"2026-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148618813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0