The translocation of wild-caught fish into captive systems represents a pathway for the introduction of ectoparasites into closed marine environments. This report documents the first record of Neobenedenia sp. (Monopisthocotylea: Capsalidae) infesting Pacific tripletail ( Lobotes pacificus ) from Costa Rica; caligid copepods of the genus Caligus were also detected. Parasite transmission under captive conditions and subsequent control measures were evaluated. An adult specimen captured near Isla Venado (Gulf of Nicoya) was transferred to a marine park facility containing conspecifics. Approximately one month later, transmission of Neobenedenia sp. to resident fish was detected. Parasites were identified morphologically at the genus level. Control measures targeting the Neobenedenia infestation included temperature-adjusted freshwater baths and nylon-thread collectors to monitor egg deposition. Repeated treatments combined with egg monitoring resulted in absence of Neobenedenia sp. eggs, confirming interruption of its life cycle and cessation of transmission. This report provides baseline parasitological information for L. pacificus in Costa Rica and highlights the importance of parasite identification and structured quarantine protocols based on parasite developmental biology to prevent establishment of ectoparasite infestation in marine display and aquaculture systems.
Generative artificial intelligence (GenAI) is influencing how research is conducted and reported, however there is limited agreement on what constitutes acceptable use in scholarly publishing. Publishers contribute to shaping norms around GenAI, yet journal policies vary. This study compared GenAI policies across aquaculture journals, especially those publishing research on aquatic animal diseases, to raise awareness to variability in acceptable use. GenAI policies for nine journals were analysed within four domains: Policy Status, Scope and Permissions, Author Responsibilities, and Accountability. All journals explicitly or implicitly permitted GenAI use in manuscript preparation, although detailed guidance was often lacking for specific tasks. Considerable variation existed between journals concerning the creation of figures, from permitted (1/9) and implicitly permitted (3/9) to prohibited (3/9). All journals required disclosure of GenAI use and generally provided instructions, although in some cases certain tasks did not require disclosure including use for grammar and spelling (4/9 journals). Authors were explicitly responsible for accuracy (4/9) and originality (6/9) of GenAI-assisted content, while most journals provided little explicit guidance on legalities of GenAI use or for issues pertaining to data privacy, confidentiality, intellectual property rights, and data ownership, with 4/9 journals not providing any guidance on these matters. Most journals (7/9) explicitly prohibited GenAI authorship. Actions that may help protect research integrity and trust include clearer journal guidance for GenAI use, standardised disclosure statements, and support for researcher training. This is the first study to highlight gaps and variations in aquaculture journal policies to GenAI, which supports authors and contributes to the ongoing debate around acceptable practices.
Mediterranean aquaculture is a strategic component of regional food production and the blue economy, supplying high-value marine species with a comparatively lower environmental footprint to many other animal protein systems. Yet the sector is entering a period of intensified pressure. Climate change, resource constraints, rising production costs, market competition, fragmented production structures, and increasingly complex regulatory demands are reshaping the conditions under which Mediterranean fish farming operates. At the same time, conventional husbandry practices remain heavily dependent on labor-intensive routines and limited observation of biological and environmental processes in open marine systems. This paper examines how digital transformation and precision fish farming can support a more resilient, efficient, and sustainable Mediterranean aquaculture sector. After outlining the current characteristics of marine fish farming in the region, the paper discusses the main structural, environmental, and economic challenges affecting production. It then presents precision fish farming as a management paradigm based on continuous observation, reliable data collection, quantitative analysis, and timely decision-making. Key enabling technologies are reviewed, including sensor networks, cameras, Internet of Things systems, remote sensing, drones, remotely operated and autonomous underwater vehicles, automated feeding systems, artificial intelligence, decision support systems, and digital twins. The paper also highlights current application areas such as environmental monitoring, forecasting and modeling, non-invasive monitoring of fish behavior and morphology, feeding optimization, site suitability analysis, and cage inspection. Particular attention is given to barriers to adoption, including investment cost, data quality, interoperability, capacity building, cybersecurity, data ownership, and the responsible use of artificial intelligence. The central argument is that digital transformation is no longer optional for Mediterranean aquaculture: it is becoming a prerequisite for adapting production systems to environmental uncertainty, improving operational performance, and strengthening long-term sustainability. However, successful implementation will depend not only on technology availability, but also on skills development, organizational readiness, and cross-disciplinary collaboration.
Prior to this study, only three ichthyoparasitological investigations had been conducted on the Sakarya chub, Squalius pursakensis (Hankó, 1925), an endemic cyprinid fish species in Türkiye. The present study aimed to determine the occurrence and infection parameters of caryophyllidean tapeworms naturally parasitizing this host species. A total of 98 specimens of S. pursakensis were seasonally collected throughout four seasons in 2023 from Sarısu Stream (Eskişehir, Türkiye). Seventeen individuals (17.34%) were found to be infected with one or more caryophyllidean cestodes. Only a single species, Caryophyllaeides fennica , was identified from the intestinal tract. Seasonal variation in infection parameters, as well as differences related to host length and sex, were analyzed. In addition, this study provides the first global description of histopathological alterations caused by C. fennica in a cyprinid fish species. Histopathological examination revealed erosion and degeneration of the intestinal mucosal epithelium at the scolex attachment site, characterized by close contact between the parasite and host epithelial cells, localized tissue destruction, and infiltration of inflammatory cells. The parasites were predominantly located in the anterior to middle regions of the intestine. Furthermore, S. pursakensis is reported as a new host record for C. fennica , thereby expanding the known host range and geographical distribution of this caryophyllidean cestode species.
We provide an update from the 1st PKD Network workshop, organised in 2025 during the EAFP Conference in Heraklion, Crete. The aim of the of the workshop was to link representatives of aquaculture industry, wild fisheries and academia, all interested in tackling the salmonid health challenges arising from the Proliferative Kidney Disease. This event also marked the formal launch of the PKD Network, accessible at https://pkdnetwork.wordpress.com/
The 12th Symposium on Diseases in Asian Aquaculture (DAA12) was held symposium was organized by the Fish Health Section (FHS) of the Asian Aquaculture and Fisheries, Chennai under the theme "Transformative innovations shaping the future of aquatic animal health management." A total of 470 delegates from 21 countries, including scientists, students, policymakers, and aquaculture industry representatives from Asia and other regions, attended the meeting. The scientific programme was comprehensive, comprising 18 keynote and lead presentations, 49 oral presentations, and 189 poster presentations. Major thematic areas included finfish and shrimp health, mollusc and seaweed diseases, aquatic animal diagnostics and therapeutics, emerging technologies, One Health, biosecurity, and disease surveillance.
Spontaneous Staphylococcus warneri infection was found in rainbow trout broodstocks in raceway culture where the fish were kept at a density of 110 kg m-3 and at water temperature of 7- 9 degrees C. Signs of disease occurred a week after the transport and transfer of the fish and the clinical signs of moribund fish manifested themselves as anorexia, lethargy and slow swimming on the surface of the water. The external clinical signs included exophthalmos, eye haemorrhage and pale gill. Internally there were hyperaemia over the abdominal fat in pyloric region, pale liver, yellow liver, ecchymotic or petechial haemorrhages in liver and hyperaemia of the intestinal wall; on histological examination, there was eye oedema, the liver displayed moderate or severe acute haemorrhagic hepatitis, inflammatory reaction around bile ducts, moderate focal vacuolation of hepatocytes, and congested haemorrhagic spleen, with infiltration into visceral fat. Haematological examination revealed moderate to severe cytoplasmic lesions on peripheral smear of the observed erythrocytes. The case description suggests that this might represent a secondary or opportunistic infection associated with immunosuppression due to handling stress.
Viral nervous necrosis (VNN) is a disease caused by Betanodavirus that leads to outbreaks mortality in wild or farmed marine fish. This study aimed to investigate the presence of Betanodavirus in grouper from different sites along the Algerian coast and to characterize the isolates using molecular tools. A total of twenty-three individuals were examined: one dusky grouper (Epinephelus marginatus Lowe, 1834) and twenty-two goldblotch groupers (Epinephelus costae Steindachner, 1878). The RT-qPCR detected the presence of VNN in seven individuals of Epinephelus costae, three from the center of the Algerian coast (two from Algiers and one from Gouraya) and four from the west (Mostaganem). Phylogenetic analyses of the partial sequences of RNA1 and RNA2 viral genome fragments revealed the presence of the red-spotted grouper nervous necrosis virus (RGNNV) genotype, closely related to strains previously detected in Algerian groupers and wild grouper from Spain. The results of this study confirm further that VNN disease is endemic among grouper populations in Algeria, which could be a determining factor in the observed decline of this species.
From the 1st to the 4th of September 2025, the 22nd International Conference on Diseases of Fish and Shellfish, organized by the European Association of Fish Pathologists (EAFP), was held in Heraklion, Greece. Within this international context, a dedicated workshop entitled “Nodavirus in wild fish: addressing the Mediterranean grouper mortality crisis” took place on the 3rd of September. This workshop represented the first coordinated scientific initiative focused entirely on understanding the increasing mortality events associated with Betanodavirus infection in wild groupers across the Mediterranean Sea, where unprecedented mortality levels have been recorded in Spain, Italy and Greece during the past two years.
Four large dams were removed from the Klamath River in Oregon and California, USA in 2023-24. This was the largest dam removal and restoration project in U.S. history, with a primary aim to restore critical habitat for threatened and endangered salmon populations that the dams had constrained to the lower half of the river basin for over a century. The dam removals resulted in profound physical changes to the river that are expected to alter host-pathogen dynamics in significant ways. Reconnecting the lower and upper portions of the river basin has increased habitat available to salmon, and adult salmon have already begun to return to streams upstream from the former dams where they were historically present. These fish now have longer migration routes, altering the distribution and abundance of both hosts and pathogens. To develop a management plan for the reconnected river, our workgroup drew from a combination of Western Science and Traditional Ecological Knowledge to inform disease risk predictions. While our initial synthesis included multiple pathogens for which there was evidence of disease related impacts, in this forum we focus on Ceratonova shasta, which is considered the primary pathogen limiting salmon recovery in this river system. For juvenile salmon, we predict a reduction in disease risk resulting from the decrease in overlap between infected salmonid and annelid hosts, attributable to the restoration habitats that favor salmonids but are less suitable for annelids. habitats, we predict increased risk of infection and disease resulting from associated with prespawn mortality, previously not observed in salmon in this cycle.
The Histopathology Workshop of the 22nd International Conference on Diseases of Fish and Shellfish was held in Heraklion, Greece, on 31st August 2025, one day prior to the main conference. Organized by Barbara Nowak, Heike Schmidt-Posthaus, Diane Elliott, and Patricia Noguera, the event brought together international diagnosticians, researchers, educators as well as students with a shared interest in histopathology. This year’s theme focused on finfish gill—an essential subject for diagnostics, research, and the aquaculture industry. The workshop included a keynote lecture, five introductory talks, and fourteen case presentations from contributors around the world. The next workshop is scheduled for 2027.
Carp edema virus disease, caused by the Carp Edema Virus (CEV), is an emerging disease affecting common carp (Cyprinus carpio). During early April 2023, Rama Lake in Bosnia and Herzegovina (B&H) experienced significant daily mortalities of wild common carp (Cyprinus carpio), predominantly affecting adult specimens. Despite the presence of other fish species in the lake, the mortality was exclusively observed in the common carp. The sample of 10 moribund fish was caught in a landing net and transported on ice to the Laboratory for Aquaculture of the Veterinary Institute Sarajevo. In order to examine possible viral aetiology, tissue samples were collected and DNA was extracted using standard procedures. CEV was detected by real-time PCR. All samples were real-time PCR negative for the presence of KHV and SVCV. In this study, we describe the first detection of CEVD caused by carp edema virus in wild carp in Bosnia and Herzegovina.
Lactococcosis, a disease caused by Lactococcus garvieae, L. formosensis, and L. petauri, has been continuously documented to inflict significant economic losses on cultured fish species globally. This study reported the first identification of Lactococcus petauri from reared turbot (Scophthalmus maximus) using biochemical tests, 16S rRNA gene sequence, and multiplex PCR assay with species-specific primers. The 16S rRNA partial sequence generated in this study has been deposited in the GenBank database under accession number PQ669659 and compared with available sequences in the GenBank database. To our knowledge, this study reports a L. petauri infection for the first time in flat fish aquaculture, offering valuable contributions to understanding lactococcosis systematics and molecular epidemiology both in T & uuml;rkiye and globally. This first report provides valuable insights into this species' ecological distribution, pathogenicity, and adaptability, laying the groundwork for future fish pathology and aquatic microbiology studies.
There has been an increase in the annual number of affected sites, and clinical impacts, with piscirickettsiosis in marine Atlantic salmon farms in Ireland and Scotland since 2019. A novel species of Piscirickettsia has also been confirmed in affected salmon in both countries. The aim of this note is to communicate the current status and highlight the increasing significance of the disease in European salmon farms.
Skin ulceration syndrome (SUS) is a significant disease affecting the marbled flounder (Pseudopleuronectes yokohamae) in aquaculture. This study aimed to identify the pathogen responsible for SUS outbreaks. Three bacterial species were isolated from infected flounder, with isolate Isolated strain 1 confirmed as pathogenic through artificial infection experiments. Isolated strain 1 is highly pathogenic, significantly reducing the survival rate of P. yokohamae. The strains were identified using morphological, physiological, biochemical analyses, 16S rRNA, and gyrB gene sequencing. Isolated strain 1 was found to be a Gramnegative bacillus, closely related to Vibrio splendidus. Phylogenetic analysis showed that the 16S rRNA and gyrB gene sequences of Isolated strain 1 clustered with V. splendidus, with high bootstrap confidence levels (99.09% and 100%, respectively). Consequently, V. splendidus was identified as the causative agent of SUS in P. yokohamae. Antibiotic susceptibility tests revealed that Isolated strain 1 was sensitive to norfloxacin, ciprofloxacin, enrofloxacin, ceftazidime, doxycycline and florfenicol, but resistant to tetracycline, gentamicin, erythromycin and amoxicillin. These findings provide a foundation for developing disease prevention and treatment strategies in marbled flounder aquaculture.
Antibiotics are essential medicines used in aquaculture, but their application can contribute to the global challenge of antimicrobial resistance (AMR). Effective mitigation of AMR requires concerted international effort, and countries are now expected to develop National Action Plans for Antimicrobial Resistance (NAPs) through a One Health approach. The aquaculture sector is included in NAPs, and this article seeks to raise awareness for NAPs particularly amongst aquatic health professionals and others concerned with aquatic animal health, describing what NAPs are and how they can affect the aquaculture sector. Heightened awareness of NAPs can help to prepare for the policy changes these documents drive, and may open up opportunities to contribute to and influence the content of subsequent versions.
Turbot (Scophthalmus maximus) is a key representative species in flatfish aquaculture, known for its rapid growth and high meat yield, making it economically significant. Vibriosis, caused by various Vibrio species, continues to result in substantial economic losses in marine aquaculture worldwide. This study investigated bacterial diseases in cultured juvenile turbots throughout a year. Partial 16S rRNA sequences from all bacterial isolates were analyzed by comparison with sequences in the GenBank database, and accession numbers were deposited accordingly. Sixteen bacterial isolates representing eight species, primarily Vibrio spp., were identified using partial 16S rRNA gene sequencing. All isolates were sensitive to enrofloxacin, florfenicol, and gentamicin, while resistance was observed against penicillin, amoxicillin, and others. This study provides critical insights into the bacterial agents related to flatfish aquaculture, contributing to the systematics and molecular epidemiology of turbot bacterial flora. Notably, as the first report focusing on T & uuml;rkiye's turbot production, it offers valuable perspectives on the ecological distribution, pathogenicity, and adaptation of bacteria, thereby establishing a foundation for future research in turbot pathology and aquatic microbiology.
Peruvian ornamental fish industry is based on the trade of wild-caught Amazonian species, which are exported to several countries. Throughout the ornamental fish value chain, fish are exposed to different stressors, which enhance their susceptibility to pathogens. Major emerging viral diseases in ornamental fish may result in trade restrictions. Therefore, it is important for authorities to monitor the health status of ornamental fish populations. The aim of this study was to detect the presence of the genera Megalocytivirus and Ranavirus in five ornamental fish species from the Peruvian Amazon. A total of 600 wild-caught ornamental fish of five species were collected from ornamental fish wholesale facilities in the city of Iquitos, Peru, between June and September 2022. The samples included the species Hyphessobrycon erythrostigma, Corydoras splendens, Carnegiella strigata, Pterophylum scalare and Ancistrus temminckii and were analyzed by quantitative PCR (qPCR) and histopathology. The qPCR results did not detect Megalocytivirus and Ranavirus. In addition, histopathology revealed the presence of monogenoids and Piscinoodinium sp. in the gills and metacercarial cysts in the liver. Furthermore, histopathological examination revealed an unusual finding of Ichthyophthirius sp. in the esophagus of A. temminckii. The results showed that Megalocytivirus and Ranavirus were not detected during the sampling periods in at least five wild-caught ornamental fish species from the Peruvian Amazon and there are no histopathological lesions related to Megalocytivirus-infected fish. Finally, we advise that additional monitoring is necessary to detect the occurrence of the World Organization for Animal Health (WOAH) listed diseases in ornamental fish and develop strategies that ensure surveillance plans to consider the wide variety of Amazonian fish species in the ornamental fish trade, as well as the presence of disease-susceptible ornamental fish species.
This pilot research focused on investigation of the parasites infecting carpet shell clam (Ruditapes decussatus L.) from & Idot;zmir Bay. The sampling material consisted of randomly selected 360 carpet shell clams collected from & Idot;zmir Bay during the period between October 2023 and September 2024. Rich parasite fauna was unveiled consisting of one protozoan and five metazoans, respectively a protozoan Ancistrum spp. and metazoans Cercaria tapidis (Monorchis parvus Looss 1902), Urastoma cyprinae, symbiotic copepod, nematode larva and cestode larva. The most severe pathological impact was observed in the tissues infected with the nematode larvae. There was discernable pattern in seasonal abundances, more parasites encontered in warmer months except the symbiotic copepod which preffered clams as its host in cooler months.
Despite continued growth in aquaculture, infectious diseases remain a critical concern causing annual losses of up to 10 pound billion. Many chemical treatments, widely used in the past, have now been banned due to their toxic effects on humans, fish and the environment. This sparked a shift towards natural compounds and herbal remedies that can reduce fish pathogens when incorporated in host diets. The challenge though is to find that 'needle in the haystack'- which of these compounds are most effective. Here, a reliable and consistent method was used that allows us to test the anti-parasitic activities of a botanical compound in multiple rounds, using the guppy-Gyrodactylus turnbulli system. Our blind feed trials confirm the efficacy of a commercially available product, Apex (R) (a mixture of organic acids, inactivated yeast and yeast extracts, herbal extracts and essential oils) significantly reduced parasite burden and increased host survival rate. Even though efficacy of natural compounds is both dose-and source-dependent, they can be adjusted according to host-parasite species and method of application. Additionally, feeding prior to parasite exposure likely enhances fish immune function, working synergistically with the direct effect that therapeutants have on the parasite. Concluding, Apex is a promising health-supporting natural functional feed additive, and botanicals can provide significant health benefits, urgently needed to protect the increasing global demand for suitable fish food.
