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The rapid increase in aquaculture over the last several decades has led to concerns about the environmental impact of fish feeds relying on marine resources for fishmeal (FM). We aim to assess Nannochloropsis sp. QH25 co-product as a viable and sustainable replacement for FM in juvenile rainbow trout, Oncorhynchus mykiss, feeds. We formulated four experimental diets: a reference (FM based), 33N, 66N, and 100N diet (33%, 66%, and 100% co-product replacement). Rainbow trout were randomly assigned to one of 16 tanks and randomly assigned an experimental diet to consume throughout the experiment (64 days total), with four replicate tanks per diet. We compared the phosphorus (P) and nitrogen (N) digestibility, emissions, and growth between diets and, compared six environmental impacts (biotic resource use (BRU), global warming potential (GWP), water use, land use, marine eutrophication potential (MEP), and freshwater eutrophication potential (FEP)) of each diet. Our results indicate that replacing FM with co-product did not significantly alter growth. P digestibility of the experimental and reference diets was comparable. BRU conversion ratio was significantly lower in the experimental diets. However, there were significantly higher water and land use conversion ratios but insignificantly higher results in GWP, MEP, and FEP between the reference and 100N diet.

Integrated multi-trophic aquaculture, or IMTA, attempts to reduce or eliminate nutrient loading by introducing lower trophic organisms to consume waste matter. These organisms should be capable of consuming bottom detritus with dissolved and particulate organic matter such as feces and unconsumed feed from upper trophic species. The viability of sea cucumber integration into land-based aquaculture production facilities was investigated and discussed. The focus of the study was on the role of the sea cucumber as an ecosystem service. Consumption of nutrient-loaded waste is essential in reducing eutrophication and maintaining an ecological balance. I worked with Kauai Sea Farm’s (KSF) Dave Anderson (MAS MBC ’16), investigated and compiled the most recent findings in integrating sea cucumbers into their aquaculture farm at Nomilo Fishpond with a focus on sediment analysis and comparison of biomass of sea cucumbers used in this study.The primary goal of this preliminary study was to investigate the potential benefit of integrating sea cucumbers into existing aquaculture systems to clean up and reduce waste and at the same time improve environmental outcomes. This study highlights the viability of sea cucumber integration into land-based aquaculture farms, which addresses the value of waste reprocessing,and will significantly impact the future success of aquaculture farms.Please see media created in support of this project here: https://storymaps.arcgis.com/stories/13539350ebe648baa3b3ab1a1fb61e8a

The global seaweed aquaculture industry is rapidly expanding due to the diversity of applications and sustainability benefits. Despite its global historical and cultural significance, seaweed remains underutilized in Western diets. This project investigates barriers to the culinary use of domestically-farmed seaweed in the United States, focusing on chefs' perceptions and knowledge gaps. Through collaboration with chefs and seaweed farms, the project developed educational resources and recipes to showcase the culinary versatility of eight seaweed species. The findings highlight challenges in seaweed accessibility and consumer acceptance, proposing targeted educational initiatives to enhance the domestic seaweed market and promote its culinary adoption.Please see media created for this project here: https://tinyurl.com/5n88mk8n

The blue economy is an area of growing investment and evolution across industries, governments, and communities. The rising global population coupled with rapid development in technology and trade has spurred governments across the world to look to the ocean for new sources of economic growth. While the ocean has historically been seen as an endless source of protein and extractive resources, the impacts of climate change are revealing the fallacy of this long-held assumption. Ocean acidification, warmer temperatures, and rising sea levels are resulting in habitat and biodiversity loss, extreme weather patterns, and changes to fish stock compositions and migration patterns. As a result of these changes, it is increasingly important to ensure a sustainable coexistence between humans and marine ecosystems. By developing a blue economy that prioritizes not only economic growth, but also the health of the environment and the livelihoods of local communities, it is possible to build a lasting blue economy for generations to come. The following paper analyzes existing blue economy frameworks utilized around the world to inform a model that assesses the feasibility of implementing blue economy programs in U.S. National Marine Sanctuaries.

UNLABELLED: Piscine lactococcosis is a significant threat to cultured and wild fish populations worldwide. The disease typically presents as a per-acute to acute hemorrhagic septicemia causing high morbidity and mortality, recalcitrant to antimicrobial treatment or management interventions. Historically, the disease was attributed to the gram-positive pathogen Lactococcus garvieae. However, recent work has revealed three distinct lactococcosis-causing bacteria (LCB)-L. garvieae, L. petauri, and L. formosensis-which are phenotypically and genetically similar, leading to widespread misidentification. An update on our understanding of lactococcosis and improved methods for identification are urgently needed. To this end, we used representative isolates from each of the three LCB species to compare currently available and recently developed molecular and phenotypic typing assays, including whole-genome sequencing (WGS), end-point and quantitative PCR (qPCR) assays, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), API 20 Strep and Biolog systems, fatty acid methyl ester analysis (FAME), and Sensititre antimicrobial profiling. Apart from WGS, sequencing of the gyrB gene was the only method capable of consistent and accurate identification to the species and strain level. A qPCR assay based on a putative glycosyltransferase gene was also able to distinguish L. petauri from L. garvieae/formosensis. Biochemical tests and MALDI-TOF MS showed some species-specific patterns in sugar and fatty acid metabolism or protein profiles but should be complemented by additional analyses. The LCB demonstrated overlap in host and geographic range, but there were relevant differences in host specificity, regional prevalence, and antimicrobial susceptibility impacting disease treatment and prevention. IMPORTANCE: Lactococcosis affects a broad range of host species, including fish from cold, temperate, and warm freshwater or marine environments, as well as several terrestrial animals, including humans. As such, lactococcosis is a disease of concern for animal and ecosystem health. The disease is endemic in European and Asian aquaculture but is rapidly encroaching on ecologically and economically important fish populations across the Americas. Piscine lactococcosis is difficult to manage, with issues of vaccine escape, ineffective antimicrobial treatment, and the development of carrier fish or biofilms leading to recurrent outbreaks. Our understanding of the disease is also widely outdated. The accepted etiologic agent of lactococcosis is Lactococcus garvieae. However, historical misidentification has masked contributions from two additional species, L. petauri and L. formosensis, which are indistinguishable from L. garvieae by common diagnostic methods. This work is the first comprehensive characterization of all three agents and provides direct recommendations for species-specific diagnosis and management.

Blood cockle sampling and water quality monitoring were conducted monthly between September 2011 and June 2013 at four blood cockle aquaculture farms situated along the Selangor coast, of Malaysia. Histological observations of the gonads were performed to identify male and female blood cockles. The maturation of gonadal tissue was evaluated, and the relationship between the maturation status of blood cockles and water quality factors, such as salinity and chlorophyll a concentration, was examined at each station. Mature and spawning male cockles were present year-round at all stations except at Station C, where males were more susceptible to the influence of the estuary. Females exhibited a distinct seasonal change in gonadal tissue compared with males, with a higher proportion of spent-stage individuals during the dry season. In addition, the number of immature individuals, for which it was difficult to distinguish between males and females, increased during that period. These results showed that spawning activity on the Selangor coast is more prominent during the rainy season and less pronounced during the dry season. The relationship between salinity, chlorophyll a concentration, and the gonadal tissue maturation stage of the cockle was identified. These findings reveal that sexual maturation progressed in brackish water with a salinity of approximately 28 in both males and females. As salinity decreased to less than 25, the proportion of immature and spent-stage individuals that released sperm or eggs increased. Additionally, immature individuals' percentage increased when chlorophyll a concentration was low ( KEY WORDS: sexual maturation, blood cockle, Tegillarca granosa, Selangor, Malaysia, INTRODUCTION Also known as Anadara granosa (Linnaeus, 1758), Tegillarca granosa (Linnaeus, 1758) is a blood cockle. It is morphologically defined by approximately 18 ribs and numerous nodules on the shell [...]

Globalization of fishery products is playing a significant role in shaping the harvesting and use of aquatic foods, but a vigorous debate has focused on whether the trade is a driver of the inequitable distribution of aquatic foods. Here, we develop species-level mass balance and trophic level identification datasets for 174 countries and territories to analyze global aquatic food consumption patterns, trade characteristics, and impacts from 1976 to 2019. We find that per capita consumption of aquatic foods has increased significantly at the global scale, but the human aquatic food trophic level (HATL), i.e., the average trophic level of aquatic food items in the human diet, is declining (from 3.42 to 3.18) because of the considerable increase in low-trophic level aquaculture species output relative to that of capture fisheries since 1976. Moreover, our study finds that trade has contributed to increasing the availability and trophic level of aquatic foods in >60% of the worlds countries. Trade has also reduced geographic differences in the HATL among countries over recent decades. We suggest that there are important opportunities to widen the current focus on productivity gains and economic outputs to a more equitable global distribution of aquatic foods.

The global population consumes more seafood from aquaculture today than from capture fisheries and although the aquaculture industry continues to grow, both seafood sectors will continue to be important to the global food supply into the future. As farming continues to expand into ocean systems, understanding how wild populations and fisheries will interact with farms will be increasingly important to informing sustainable ocean planning and management. Using a spatially explicit population and fishing model we simulate several impacts from ocean aquaculture (i.e., aggregation, protection from fishing, and impacts on fitness) to evaluate the mechanisms underlying interactions between aquaculture, wild populations and fisheries. We find that aggregation of species to farms can increase the benefits of protection from fishing that a farm provides and can have greater impacts on more mobile species. Splitting total farm area into smaller farms can benefit fishery catches, whereas larger farms can provide greater ecological benefits through conservation of wild populations. Our results provide clear lessons on how to design and co-manage expanding ocean aquaculture along with wild capture ecosystem management to benefit fisheries or conservation objectives.

ABSTRACT The cobia (Rachycentron canadum) is important to fisheries in Northeastern Brazil. To restore stocks in Rio Grande do Norte, cobia were stocked and the fishery was monitored over 4 years. We evaluated effects of stocking on cobia size composition in this data‐limited fishery to understand stocking limitations and explore possibilities for future projects. Total length of cobia was significantly shorter after stocking than before stocking, with mostly small fish caught mainly by nets, an unusual pattern for cobia. Total length also varied significantly among bottom types. Most of the cobia harvested were below the size at first maturity, which suggests that stocking increased the catch, but most fish harvested were immature, thereby potentially hindering stock recovery. For future projects, we recommend against the use of plastic tags for tagging hatchery cobia and propose releases that emulate natural spawning dynamics, alongside releasing fish at older ages. Further, we recommend robust post‐stocking fishery monitoring, and management strategies, such as a release of net‐caught cobia in the initial 2 years and incorporating validated fisher knowledge into decision‐making. [ABSTRACT FROM AUTHOR]

Aeromonas salmonicida and Yersinia ruckeri are common pathogenic bacteria that impact salmonid aquaculture. Although vaccinations are available against both organisms, large-scale vaccination efforts can be expensive, cumbersome, and are not always reliable. Alternatively, these pathogens have been effectively inactivated using UV radiation from mercury-based systems. These systems are energy intensive and fragile which currently limits their use to closed and semi-closed production systems. UV light emitting diodes (UV LEDs) have recently emerged as a novel alternative to traditional mercury-based treatment. UV LEDs have durable housing, a relatively low energy draw, can be powered by a battery source and are adaptable to challenging environments. This study examined the effectiveness of three UV LED wavelengths for disinfection of A. salmonicida and Y. ruckeri in pure culture and resuspended in a wastewater matrix. All tested UV LEDs were effective in disinfecting both organisms. 267 and 279 nm wavelengths outperformed 255 nm disinfection in both test matrices. Particulate matter from wastewater reduced the upper limit of treatment for A. salmonicida but results still indicated that all wavelengths were effective for disinfection in a challenging matrix. This study represents the first use of UV LEDs for disinfection of A. salmonicida and Y. ruckeri and provides impact to aquaculture producers looking to implement novel technologies for disease control. [ABSTRACT FROM AUTHOR]

ABSTRACT This research introduces an innovative power management approach for wireless sensor networks in aquatic environmental monitoring. The study presents a dynamic algorithm that optimizes energy consumption in long range (LoRa) communication nodes by adaptively adjusting transmission power based on sensor–gateway distances. Leveraging GPS data and a log‐normal shadowing model, the method enables efficient power allocation. Field testing in an aquaculture setting demonstrates the energy‐aware power control (EAPC) algorithm's efficacy. Nodes at 500 m from gateways achieve up to 39% reduction in power consumption compared to fixed‐power systems. At 1250 m, savings decrease to 22%, and at 1500 m, to 11%, while maintaining reliable communication. This research advances sustainable aquatic resource management, offering applications in aquaculture, environmental conservation, and water resource management. By optimizing power usage, the approach contributes to more effective long‐term monitoring of aquatic environments. [ABSTRACT FROM AUTHOR]

Aquaculture contributes to agricultural development, economic growth, and poverty reduction initiatives in Zambia. In northern and rural regions of the country, development requires improvements to the management of local and farm-generated inputs. Fish farmers have limited market access and purchasing power, which restricts access to commercial inputs, such as formulated feeds and chemical fertilizers. Instead, farmers adopt integrated-agriculture-aquaculture (IAA) practices, whereby on-farm resources supply essential inputs. Research is limited regarding local systems of resource management, and this hinders development of innovations for improving efficiency. This mixed-methods study explored local patterns of resource utilization. Smallholders (n = 63) participated in surveys and interviews regarding resource management. A series of quantitative analyses, including descriptive statistics, principal component analyses (PCA), and multinomial logistic regression (logit) models, identified relationships between these resources, household livelihood, and system productivity. Qualitative analyses explored farmer perceptions regarding seasonal resource availability. Results suggested that livestock manure, homemade feeds comprising maize and soybean, garden residues, and kitchen wastes were the most frequently selected inputs. Logit models of feeding intensity found that income, proximity to Luwingu Town, experience in aquaculture, and access to extension services were key household resources. High-intensity feeding strategies incorporated commercial feeds, chemical fertilizers, as well as home-made feeds containing a wide diversity of both high- and low-quality ingredients. Low-intensity feeding strategies incorporated only farm waste and termites. Potential innovations that may improve system performance in resource poor contexts are considered and recommendations for additional research are offered. [ABSTRACT FROM AUTHOR]

ABSTRACT Fin abnormalities are common in reared fish. They mainly consist of partial to complete lack of rays and severe abnormalities of fin‐supporting skeletal elements, which develop during the larval stage, up to the completion of fin skeleton ontogeny. This study reports a new abnormal condition, ray‐resorption syndrome (RSS), which developed after the completion of fin ontogeny in initially normal European seabass larvae, leading to extensive loss of fin rays. At 49 days post‐fertilisation (dpf) (15 mm standard length, SL) all fish presented normal fins. However, nineteen days later (21 mm SL), significant fin damage, characterised by ray loss or fractures, was observed in all studied populations. The dorsal fin was most affected (55%–84%), followed by the pelvic (27%–53%) and anal fins (7%–17%). Microscopically, multiple non‐mineralised areas resembling resorption lacunae were evident along all fin lepidotrichia. By 98 dpf (40 mm SL), the fin‐ray loss had advanced, reaching its higher frequency in the dorsal (74%–83%) and caudal fins (71%–94%). Gene expression analysis revealed a significant upregulation of bglap (osteoblast maturation marker), acp5a (osteoclast maturation marker) and mmp13a (extracellular‐matrix remodelling marker) in RSS specimens. The results are discussed in respect of the possible causative factors of RSS. [ABSTRACT FROM AUTHOR]

Introduction: Aquaculture has been considered a major food-producing sector in the world during the last few decades. The foremost constraint in the development of aquaculture is bacterial disease control and management. Since various fish pathogens are resistant to conservative treatments, it is essential to screen new and effective alternative antibacterial agents. Endophytic fungi are microorganisms that live in the plant's internal tissues without harming its host. Endophytic fungi have proven themselves as reliable sources of novel bioactive compounds that can be used as antibacterial agents. Methods: In the present study, fifteen morphologically different endophytic fungi were isolated from the fresh and healthy stem section of Centella asiatica. The active endophytic fungal crude extracts were tested for agar well diffusion assay, Minimum Inhibitory Concentration, Minimum Bactericidal Concentration assays, Time-kill kinetic analysis, Brine shrimp lethality assay. Results and Discussion: Agar plug diffusion and agar well diffusion assays revealed that endophytic fungus CAS1 exhibits maximum antagonistic activity against bacterial fish pathogens. The ethyl acetate crude extract of CAS1 exhibited the maximum zone of inhibitions against Aeromonas hydrophila (21 ± 0.11 mm), Aeromonas caviae (18 ± 0.1 mm), Edwardsiella tarda (23 ± 0.11 mm), Vibrio anguillarum (19 ± 0.05 mm) and Vibrio harveyi (20 ± 0.27 mm). The MIC and MBC values extract varied reliant on the trial pathogens ranging between 12.5-100 μg/mL and 25-100μg/mL correspondingly. The morphological and molecular characterization of potential isolate CAS1 was confirmed as Paradendryphiella arenariae by 18S rRNA ITS gene sequencing with 99.18% identity. This is the foremost findings to study the antagonistic effect of Paradendryphiella arenariae isolated from the stem of Centella asiatica against bacterial fish pathogens which can be used as natural effective antibacterial agents in aquaculture. [ABSTRACT FROM AUTHOR]

The sustainability of the salmon farming industry is being challenged by increased mortality rates. Scotland's open-source salmon production data provides the possibility of developing an industry-wide mortality monitoring model, valuable for identifying and addressing unexpected increases in mortality without needing data sharing agreements across different companies. This study aimed to utilize these data to develop a hierarchical dynamic linear model (DLM) for monitoring monthly mortality of maricultured Atlantic salmon in Scotland. We evaluated whether considering the hierarchical structure present in the data (country, region, and site) would improve mortality predictions when compared to the production cycle level DLMs developed in a previous study. Our findings demonstrated that the hierarchical DLM outperformed the production cycle level DLMs, confirming the value of this more complex modelling approach. Nevertheless, the hierarchical model, like the production cycle level DLMs, exhibited some uncertainty in the mortality predictions. When mortality is higher than expected, site level warnings are generated, which can encourage producers and inspectors to further investigate the cause. Between 2015 and 2020, approximately 25% of the production cycles and 50% of the sites encountered at least one warning, with most warnings happening in the summer and autumn months. Additionally, the hierarchical model enabled monitoring mortality at multiple levels. This information is useful for various stakeholders as part of a monitoring system, offering insights into mortality trends at national, regional, and sites levels that may benefit from strategic resource management. Recommendations for model improvements include utilizing shorter data aggregation periods, such as weekly, which are not currently available as open-source data. [ABSTRACT FROM AUTHOR]

Aquaculture in exposed and/or distant ocean sites is an emerging industry and field of study that addresses the need to improve food security along with the challenges posed by expansion of urban and coastal stakeholders into nearshore and sheltered marine waters. This move necessitates innovative solutions for this industry to thrive in high-energy environments. Some innovative research has increased understanding of the physics, hydrodynamics, and structural requirements enabling the development of appropriate systems. The blue mussel (Mytilus edulis), the New Zealand green shell or green lipped mussel (Perna canaliculus), and the Pacific Oyster (Magallana gigas), are the primary targets for commercial exposed bivalve aquaculture. Researchers and industry members are actively advancing existing structures and developing new structures and methodologies for these and alternative high-value species suitable for such conditions. For macroalgae (seaweed) cultivation, such as sugar kelp (Saccharina latissimi), oar weed (Laminaria digitata), or kelp sp. (Ecklonia sp.), longline systems are commonly used, but further development is needed to withstand fully exposed environments and improve productivity and efficiency. In marine finfish aquaculture, three primary design categories for open ocean net pens are identified: flexible gravity pens, rigid megastructures, closed pens, and submersible pens. As aquaculture ventures into more demanding environments, a concerted focus on operational efficiency is imperative. This publication considers the commercial and research progress relating to the requirements of aquaculture's expansion into exposed seas, with a particular focus on the cultivation of bivalves, macroalgae, and marine finfish cultivation technologies and structural developments. [ABSTRACT FROM AUTHOR]

Research that informs the New Hampshire Aquaculture industry, which has grown significantly over the past few years, and helps the overall associated watershed community to keep Great Bay Estuary healthy is vital. Specific study of green crabs, Carcinus maenas , and their potential effects on oysters, Crassostrea virginica , is important to gain a better understanding of the impact invasive species may have on these ecologically and economically important bivalves. The aim of this study was to document and understand New Hampshire (NH) oyster growers' perspectives on the issue of green crab predation of oysters. Through a survey, this study documented a preliminary understanding of farmer perspectives and research needs regarding the population of green crabs in NH waters. More specifically, this survey provided a social science perspective and information on areas of potential research - abundance, distribution, and diet of green crabs - that could be beneficial to the oyster industry. This study fills knowledge gaps, helps improve future research (including how to better engage with end users), and facilitates creating and implementing solutions that benefit the NH oyster aquaculture industry. [ABSTRACT FROM AUTHOR]

Viral nervous necrosis (VNN) poses a significant threat to the aquaculture industry, causing substantial losses and economic burdens. The disease, attributed to nervous necrosis viruses within the Betanodavirus genus, is particularly pervasive in the Mediterranean region, affecting various fish species across all production stages with mortality rates reaching 100%. Developing effective preventive measures against VNN is imperative. In this study, we employed rigorous immunoinformatics techniques to design a novel multi-epitope vaccine targeting VNN. Five RNA-directed RNA polymerases, crucial to the lifecycle of Betanodavirus, were selected as vaccine targets. The antigenicity and favorable physicochemical properties of these proteins were confirmed, and epitope mapping identified cytotoxic T lymphocyte, helper T lymphocyte, and linear B lymphocyte epitopes essential for eliciting a robust immune response. The selected epitopes, characterized by high antigenicity, non-allergenicity, and non-toxicity, were further enhanced by adding PADRE sequences and hBD adjuvants to increase immunogenicity. Two vaccine constructs were developed by linking epitopes using appropriate linkers, demonstrating high antigenicity, solubility, and stability. Molecular dynamics simulations revealed stable interactions between the vaccine constructs and Toll-like receptors (TLRs), essential for pathogen recognition and immune response activation in fish. Notably, vaccine construct V2 exhibited superior stability and binding affinity with TLR8, suggesting its potential as a promising candidate for VNN prevention. Overall, our study presents a comprehensive approach to VNN vaccine design utilizing immunoinformatics, offering safe, immunogenic, and effective solutions across multiple Betanodavirus species. Further experimental validation in model animals is recommended to fully assess the vaccine's efficacy. This research contributes to improved vaccine development against diverse fish pathogens by addressing emerging challenges and individualized immunization requirements in aquaculture. [ABSTRACT FROM AUTHOR]

\nIMPACT STATEMENTPrevious studies have achieved success in obtaining cultured juveniles of the sea urchin Salmacis sphaeroides, but few have reported their reproduction potential and development rates. This comprehensive study examined the spawning potential of broodstock and described embryonic, larval and juvenile development. The broodstock consisted of wild-caught specimens from Singapore’s coastal waters that were regularly provided a mixed animal-plant diet comprising 3 g prawn and 3 g corn. Gametes were obtained using 0.5 M of potassium chloride (KCl) injection into the coelomic cavity. Fertilization rates of the 32 spawning attempts varied from 42.9% to 100%. Hatched larvae were subsequently reared with a density of 0.5 larvae ml−1 in 50 µm filtered seawater at 28°C and fed 20,000 cells ml−1 of Tisochrysis lutea once every 2 days. Despite the presence of natural biofilms as settlement cues, the settlement rates in culture were very low and variable (2.08–9.78%). The majority of juvenile S. sphaeroides from F1 and F2 generations was sexually mature at ≥35 mm in test diameter, and the sex ratios were female-biased, ranging from 1:1.14 to 1:8. Findings from this study open up new opportunities for developing tropical sea urchin cultures under controlled rearing systems that can guarantee production. Salmacis sphaeroides metamorphosis was induced using natural biofilms but had poor settlement ratesRecommendation to induce spawning only in adult Salmacis sphaeroides that are at ≤35 mm in test diameter and at least 10 months oldFemale-biased sex ratios of lab-grown F1 and F2 generationsSalmacis sphaeroides metamorphosis was induced using natural biofilms but had poor settlement ratesRecommendation to induce spawning only in adult Salmacis sphaeroides that are at ≤35 mm in test diameter and at least 10 months oldFemale-biased sex ratios of lab-grown F1 and F2 generations [ABSTRACT FROM AUTHOR]

The quality of water used in aquaculture ponds is one of the crucial factors influencing the smell and sensory properties of fish. The water samples were taken from the rainbow trout fish ponds from three different fish farms in three provinces in Türkiye in four different seasons. The samples were analyzed for the volatile components by employing HS-SPME/GC–MS. Seven different volatile groups including aldehydes, ketones, esters, alcohols, volatile phenols, terpenes and other aromatic substances were identified in the samples. Among these, aldehydes were found to be the most dominant. (E)-2-Heptenal, nonanal, acetophenone, and 2-ethyl-1-hexanol are thought to be responsible for the off-odors in the water that have the potential to cause off-odors in fish. It was also determined that the amounts of these compounds increases in winter due to lower water temperature. Fish producers should monitor water quality on a regular basis to prevent off-odor compounds that degrade fish quality. [ABSTRACT FROM AUTHOR]

Bay-scale empirical evaluations of how bivalve aquaculture alters plankton composition, and subsequently ecological functioning and higher trophic levels, are lacking. Temporal, inter- and within-bay variation in hydrodynamic, environmental, and aquaculture pressure complicate plankton monitoring design to detect bay-scale changes and inform aquaculture ecosystem interactions. Here, we used flow cytometry to investigate spatio-temporal variations in bacteria and phytoplankton (< 20 μm) composition in four bivalve aquaculture embayments. We observed higher abundances of bacteria and phytoplankton in shallow embayments that experienced greater freshwater and nutrient inputs. Depleted nutrient conditions may have led to the dominance of picophytoplankton cells, which showed strong within-bay variation as a function of riverine vs marine influence and nutrient availability. Although environmental forcings appeared to be a strong driver of spatio-temporal trends, results showed that bivalve aquaculture may reduce near-lease phytoplankton abundance and favor bacterial growth. We discuss confounding environmental factors that must be accounted for when interpreting aquaculture effects such as grazing, benthic-pelagic coupling processes, and microbial biogeochemical cycling. Conclusions provide guidance on sampling considerations using flow cytometry in aquaculture sites based on embayment geomorphology and hydrodynamics. [ABSTRACT FROM AUTHOR]

Lymphocystis viral disease (LVD) is a highly transmissible disease known to affect multiple fishes worldwide. Although this disease is usually benign, mortalities can occur in cases where infection is severe or secondary infection with bacterial pathogens and parasites occur. However, little is known about the bacterial dynamics of fish with LVD or what bacterial pathogens may be responsible for secondary infections. Here we assessed the effects of LVD on the skin microbiome of gilthead seabream by comparing 30 symptomatic, asymptomatic and recovered (three weeks after infection) fish using 16S rRNA high-throughput sequencing. Our results show that LVD is associated with significant changes in microbiome structure and function. Importantly, fish pathogens like Tenacibaculum maritimum and some Vibrio species increased their abundance. Moreover, microbial metabolic activities of the commensal microbiota that may confer some protection to fish were suppressed in diseased fish. After reducing fish cage density to treat symptoms and three weeks of recovery, the abundance of pathogens was significantly reduced and microbiome functionality was recovered, although community structure remained significantly different. These results show that LVD can severely disrupt the bacterial communities of the skin of the gilthead seabream, leading to an increase in bacterial pathogens responsible for relevant diseases in gilthead seabream farms. [ABSTRACT FROM AUTHOR]

Evaluating the breeding performance of cultivable fish using gonadotropin-releasing hormone (GnRH) analogues is crucial for optimizing reproductive efficiency and enhancing the sustainability of aquaculture practices. However, there is a lack of understanding regarding which GnRH analogue performs best under hatchery conditions for stinging catfish. Therefore, this study was conducted to assess the breeding performance of stinging catfish (Heteropneustes fossilis) using three commercially available GnRH analogs: Wova-FH, Ovaprim, and Easy-spawn. For this purpose, an experiment was set up in a commercial hatchery by dividing the samples into three groups, each treated with one of the analogs: Wova-FH, Ovaprim, or Easy-spawn. In the experiment, a ratio of 1.5:1 male to female was maintained, and 1 mL syringes were used to inject the analogs. The results showed that the spawning induction efficiency differed among the three inducing agents. Compared to Ovaprim and Easy-spawn, Wova-FH-treated H. fossilis exhibited higher breeding success in all measured aspects. Specifically, Wova-FH achieved a latency period of 8 h, an ovulation rate of 87.25%, a fertilization rate of 89.33%, a hatching rate of 88.85%, and an incubation period of 16 h. In comparison, Ovaprim and Easy-spawn had incubation periods of 18 h and 24 h, respectively. In Ovaprim-induced individuals, the latency period was approximately 8.30 h, with an ovulation rate of 82.08%, a fertilization rate of 86.75%, and a hatching rate of 85.97%. In contrast, the Easy-spawn-induced individuals had a latency period of 9 h, an ovulation rate of 27.50%, a fertilization rate of 27.10%, and a hatching rate of 26.15%. Significant differences (p < 0.05) were observed among the treatments in both the ovulation rate, fertilization rate, latency period incubation period, and hatching rate. The findings suggest that Wova-FH is a superior alternative to Ovaprim and Easy-spawn for GnRH analogs in the induced breeding programs of H. fossilis , offering optimal yield. [ABSTRACT FROM AUTHOR]

In this paper, we develop a bioeconomic model to determine an optimal wild catch harvest and freshwater commercial aquaculture production in a lake that uses cages or floating rafts. Although off-bottom aquaculture activities have less impact on the environment compared to on-bottom aquaculture, it has negative externalities. It takes away the fishing area and hence creates pressure in the open-access fishing ground. It also changes the nutrient and ecological composition of the environment. We recommend the implementation of a reserved area to minimize the impact of fishing and aquaculture activities. The reserve also helps in improving the habitat and restocking the fish population which is declining rapidly. We determine the optimal sizes of the aquaculture and reserve and the optimal effort level that maximizes social welfare. We illustrate our findings using numerical simulations and perform an analysis of the optimal solutions with respect to biological and economic parameters involved in the model. [ABSTRACT FROM AUTHOR]

Simvastatin (SIM), a commonly prescribed drug for lowering serum-lipid, has been detected in many aquatic environments. Exposure to high concentrations of SIM in rats and aquatic organisms resulted in toxicity to hepatocytes and negative effects on development. However, there is a paucity of studies on the effects of long-term exposure to low concentrations of SIM on aquaculture species. This study aimed to analyze the effects of environmentally relevant concentrations (0.1 µg/L and 1 µg/L) of SIM exposure for two months on developing Mozambique tilapias. Surprisingly, the growth of male tilapias was enhanced after a 2-month SIM exposure. The analysis of testis histology revealed that after the SIM exposure, the development of the testis was delayed, and sperm production was reduced. Sequencing of testis transcriptomes showed that the exposure to SIM altered the expression of many genes related to the development of testes and spermatogenesis. These data suggest that a 2-month exposure to environmentally relevant concentrations of increases the growth of male tilapias by inhibiting sexual development of males. [ABSTRACT FROM AUTHOR]

Recirculating Aquaculture System (RAS) is introduced in aquaculture farming industry to reduce water resource utilization, efficient the energy and land uses, and also help minimalize the water exchange. This system enables utilization of unsuitable land and promotes a sustainable environment in aquaculture industry. Furthermore, this technology has been established and proved efficient in monitoring the aquatic animal condition subsequently helps in maintaining the water quality and help remove solid particle wastes from the aquaculture treatment. As today, RAS has been developed with more effective technologies such as the use of UV irradiation, solid capture, protein skimmer and also provided with highly techno bio-filtration set. Basically, this system was applied for broodstock maturation, nursery phase, and grow-out production. In this review article, we provide an overview of RAS between the clear water, probiotic, and biofloc technology, and the advantages of its combination. Even though RAS and biofloc is two different parallel system, the application of the probiotic and biofloc in the semi-RAS application system is intense to be investigated. The synergistic effect of RAS using this combination towards high yield aquaculture production will be highlighted in this review paper. Expectantly this review paper will generate awareness and useful information on the RAS application in the aquaculture system operation with help in maximize the impact to the aquaculture yield production. [ABSTRACT FROM AUTHOR]

Sentinel-2/MSI and Landsat-8/OLI sensors enable the mapping of ocean color-related bio-optical parameters of surface coastal and inland waters. While many algorithms have been developed to estimate the Chlorophyll-a concentration, Chl-a, and the suspended particulate matter, SPM, from OLI and MSI data, the absorption by colored dissolved organic matter, acdom, a key parameter to monitor the concentration of dissolved organic matter, has received less attention. Herein we present an inverse model (hereafter referred to as AquaCDOM) for estimating acdom at the wavelength 412 nm (acdom (412)), within the surface layer of coastal waters, from measurements of ocean remote sensing reflectance, Rrs (λ), for these two high spatial resolution (around 20 m) sensors. Combined with a water class-based approach, several empirical algorithms were tested on a mixed dataset of synthetic and in situ data collected from global coastal waters. The selection of the final algorithms was performed with an independent validation dataset, using in situ, synthetic, and satellite Rrs (λ) measurements, but also by testing their respective sensitivity to typical noise introduced by atmospheric correction algorithms. It was found that the proposed algorithms could estimate acdom (412) with a median absolute percentage difference of ~30% and a median bias of 0.002 m−1 from the in situ and synthetic datasets. While similar performances have been shown with two other algorithms based on different methodological developments, we have shown that AquaCDOM is much less sensitive to atmospheric correction uncertainties, mainly due to the use of band ratios in its formulation. After the application of the top-of-atmosphere gains and of the same atmospheric correction algorithm, excellent agreement has been found between the OLI- and MSI-derived acdom (412) values for various coastal areas, enabling the application of these algorithms for time series analysis. An example application of our algorithms for the time series analysis of acdom (412) is provided for a coastal transect in the south of Vietnam. [ABSTRACT FROM AUTHOR]

Quinolone antibiotics are widely utilized in aquaculture, but little is known about the health effects of their residues. This study used UPLC-MS/MS to analyze the distribution of 11 quinolone antibiotics in cultured fish sold in a coastal city in southeast China - Fujian Province and to assess their health risks. The study found 35.77% of 260 cultured fish samples detected quinolones, with three exceeding the MRL and one containing the banned drug ofloxacin. Of the 11 quinolones tested, three were found in cultured fish, with enrofloxacin at up to 246.0 μg kg−1, followed by ciprofloxacin and ofloxacin. The distribution of antibiotic detection rates showed no significant differences across regions or time periods; however, notable variations were observed among different fish species. The dietary exposure assessment revealed that consuming cultured fish does not pose a health risk to residents. Nevertheless, there are still instances that exceed regulatory limits. Therefore, routine monitoring and risk assessment are essential for enhancing regulatory measures and protecting public health. [ABSTRACT FROM AUTHOR]

Community composition in aquatic environments can be shaped by a broad array of factors, encompassing habitat conditions in addition to abiotic conditions and biotic interactions. This paper pertains to reaction–diffusion–advection predator–prey model featuring a variable predator habitat in advective environments, governed by a unidirectional flow. First, we establish the near‐complete global dynamics of the system. In instances where the functional response to predation conforms to Holling‐type I or II, we explore the uniqueness and stability of positive steady‐state solutions via the application of particular auxiliary techniques, the comparison principle for parabolic equations, and perturbation analysis. Furthermore, we obtain the critical positions at the upper and lower boundaries of the predator's habitat, which determine the survival of the prey irrespective of the predator's growth rate. Finally, we show how the location and length of the predator's habitat affect the persistence and extinction of predators and prey in the event of a small population loss rate at the downstream end. From the biological point of view, these results contribute to our deeper understanding of the effects of habitat on aquatic populations and may have applications in aquaculture and the establishment of protection zones for aquatic species. [ABSTRACT FROM AUTHOR]

Aquafeed additive quality and quantity remain pivotal factors that constrain the sustainability and progress of aquaculture feed development. This study investigates the impact of incorporating the benthic diatom Amphora coffeaeformis into the diet of Nile tilapia (Oreochromis niloticus) broodstock, on the blood biochemistry, steroid hormone (SH) levels and seed production efficiency. Broodstock females displaying mature ovary indications were initially combined with males at a ratio of three females to one male. A total of 384 adult Nile tilapia (288 females and 96 males) were used, with 32 fish (24 females and eight males) assigned to each of 12 concrete tanks (8 m³; 2 m × 4 m × 1 m), with three replicate tanks for each dietary treatment, throughout a 14‐day spawning cycle until egg harvest. Fish were fed one of four different dietary treatments: AM0% (control diet), and AM2%, AM4% and AM6% enriched with the diatom A. coffeaeformis at levels of 20, 40 and 60 g/kg of diet respectively. At the trial's conclusion, total protein, albumin, triglyceride and creatinine), SHs (follicle‐stimulating hormone, luteinizing hormone, free testosterone, total testosterone, progesterone and prolactin) and seeds production efficiency of Nile tilapia improved significantly (p < 0.05) in alignment with the increment of A. coffeaeformis supplementation. The findings propose that including A. coffeaeformis at levels ranging from 4% to 6% could be effectively employed as a feed additive during the Nile tilapia broodstock's spawning season. [ABSTRACT FROM AUTHOR]

The world's increasing need for protein faces challenges in aquaculture production. New applications and tools will need to be added at every stage of the manufacturing line to attain this expansion sustainably, safely, and effectively. Utilizing experimental methods to increase aquatic animal production has become more common as aquatic biotechnology has advanced. High‐throughput omics technologies have been introduced to address these issues, including transcriptomic, metabolomic, proteomic, and genomes. But it also faces many difficulties, like other food manufacturing industries. One of the best and most durable approaches to address these issues is probably to understand nutritional requirements and modify diet based on need. Molecular approaches are a subset of multiomics technology. Previously, most of the published work was devoted to the biochemical aspects of protein–lipid interactions in biological systems. In this review, we explore this idea and highlight various works that fall under the umbrella of nutrigenomics, with a particular emphasis on protein utilization and its interactions with carbohydrates and lipids. [ABSTRACT FROM AUTHOR]

The Bangiales are one of the most common seaweeds in sub-Antarctic and Southeastern Pacific upper intertidal habitats. Here we report records of an 'olpidioid' marine obligate parasite infecting Bangiales between 39°20′–41°44′S in the Southeastern Pacific for the first time. The disease resembles the 'Olpidiopsis blight disease' reported for farmed Bangiales in Japan and Korea and wild Pyropia from Scotland morphologically and developmentally. The Chilean isolate infects commercial Chilean laver or 'luche' (Porphyra sensu lato) and Bangia sensu lato from wild populations in the Southeastern Pacific. Phylogenetic markers (cox2, 18S) identify it as Olpidiopsis porphyrae. We relate the occurrence of this pathogen to both 'luche' fisheries in Chile and the potential consequences for its emergent aquaculture in the Southeastern Pacific. Highlights: The parasite Olpidiopsis porphyrae (Oomycota) is reported in Chile and the Southeastern Pacific for the first time. O. porphyrae infects Chilean Porphyra and Bangia sensu lato. The prevalence of O. porphyrae is very variable between populations, and highly seasonal in a locality of Southern Chile. [ABSTRACT FROM AUTHOR]

This study aimed to perform in vitro antiparasitic and antimicrobial tests with the essential oil (EO) of Schinus terebinthifolius against of fish and shrimp. The chemical composition of the EO of S. terebinthifolius was determined by gas chromatography. For the antiparasitic test, the protozoan Epistylis sp. obtained from parasitized Oreochromis niloticus was used, and exposed to different concentrations of EO (2%, 1%, 0.5%, 0.25%), and control with 1% grain alcohol. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) test with EO of S. terebinthifolius evaluated the antimicrobial potential, with serial dilutions starting at 2% and control with 1% grain alcohol, using the strains of Aeromonas hydrophila (2.2 × 108 CFU mL−1), Edwardsiella tarda, Vibrio parahaemolyticus, V. harveyi, and V. alginolyticus (2.0 × 108 CFU mL−1). Chemical analysis revealed that the major EO compounds of S. terebinthifolius were δ‐3‐Carene (56.00%) and α‐Pinene (16.89%). In the antiparasitic test, the concentration of 2% EO showed 100% efficacy against Epistylis sp. within 5 min. In the antimicrobial tests, the concentration of 2% EO was effective against all bacteria tested. The EO of S. terebinthifolius demonstrated antiparasitic and antimicrobial activity at a concentration of 2%, standing out as an alternative to conventional antibiotics. [ABSTRACT FROM AUTHOR]

Channel catfish (Ictalurus punctatus) and Nile tilapia (Oreochromis niloticus) are two aquaculture species of great importance. Intensive production is often hindered by poor growth performance and disease mortality. The aim of this study was to evaluate the potential of a commercial fermented yeast product, DVAQUA, on channel catfish and Nile tilapia growth performance metrics and disease resistance. Channel catfish and Nile tilapia were fed practical diets supplemented with 0%, 0.1% or 0.4% of DVAQUA over approximately 2‐month feeding periods in recirculation aquaculture systems. To assess the potential of the postbiotic against common aquaculture pathogens, juvenile catfish were subsequently challenged by immersion with Edwardsiella ictaluri S97‐773 or virulent Aeromonas hydrophila ML09‐119. Nile tilapia juveniles were challenged by injection with Streptococcus iniae ARS‐98‐60. Serum lysozyme activity, blood chemistry and growth metrics were measured at the end of the feeding period, but no differences were observed across the different metrics, except for survival. For the pathogen challenges, there were no differences in endpoint mortality for channel catfish with either pathogen (p >.05). In contrast, Nile tilapia survivability to S. iniae infection increased proportionally to the inclusion of DVAQUA (p =.005). Changes to sera lysozyme activity were also noted in the tilapia trial, with a reduction of activity in the fish fed the 0.4% DVAQUA diet compared to the control diet (p =.031). Expression profiles of proinflammatory genes and antibodies were also found to be modulated in channel catfish fed the postbiotic, indicating some degree of protective response. These results suggest that this postbiotic may be beneficial in protecting Nile tilapia against S. iniae infection by influencing immune parameters and additional research is needed to evaluate the potential of this DVAQUA for improving catfish health and disease control. [ABSTRACT FROM AUTHOR]

In 2021, White Trevally or Striped Jack cultured in the western part of Japan exhibited mild, but chronic mortalities from late September through early October. The cumulative mortality rate was approximately 0.02% per a net pen containing approximately 50,000 fish. Although the cumulative mortality rate was not high, most of the fish in net pens showed characteristic gross signs and an abnormal swimming behaviour. The body of diseased fish became pale and the yellow lines on the lateral sides of fish body became darken. In addition, silver lines along the dorsal fin became apparent. Loss of schooling behaviour was noted during the mortality event. In addition, affected fish became lethargic and failed to swim against current, or frequently stopped swimming and sank to the bottom of net pens after feeding. The goal of this study was to identify the cause of the mortality event. To achieve the goal, we used histopathology and metatranscriptome analysis. Histopathological examination revealed that xenoma of microsporidian were frequently observed in the nerve axon in the brain and spinal cord. Spores observed in the sections were stained with a fluorescent dye, Uvitex 2B, indicating those spores are microsporidian. The data from metatranscriptome analysis indicated that the microsporidian is Spraguea sp. The microsporidian was frequently detected from diseased fish with similar symptoms collected in the same region, suggesting that the microsporidian was highly associated with abnormal swimming behaviour of fish. [ABSTRACT FROM AUTHOR]

The Pacific oyster (Crassostrea gigas) has been cultured for its flesh in the Seto Inland Sea, western Japan, over the last half‐century. Its production has been reported as 'fluctuating', yet little is known about changes in oyster growth performance throughout long‐term culturing in this locality. To effectively manage oyster production under future environmental challenges, this study investigated the long‐term environmental influences on oyster growth performance. Environmental data and oyster biological data were obtained from observations in Hinase waters, Seto Inland Sea, and compared for the two periods 1990 and 2015–2021. Water temperature has not significantly changed in this locality during the oyster culturing period. Lower salinity was found in July of 2015–2021 due to heavy seasonal rainfall, which had a negative impact on oysters, specifically on survival rate and total weight. A high growth rate and high meat weight at harvest were found in the individuals cultured during the period 2015–2021, yet oyster total weight showed no significant difference. Further research on shell characteristics is required to have a better understanding of oyster growth characteristics. [ABSTRACT FROM AUTHOR]

Shellfish aquaculture is a globally expanding industry, including in urban estuaries that support non‐breeding waterfowl. The effects of shellfish aquaculture on the spatial distribution of non‐breeding waterfowl, however, are poorly understood and depend on the ecology of waterfowl and cultivated shellfish species. We investigated how proximity to shellfish aquaculture influenced habitat selection and movement patterns of American black ducks (Anas rubripes) during the non‐breeding season (~Oct–May) in 2020–2023 in Rhode Island, USA. The extent to which proximity to aquaculture influenced habitat selection of black ducks depended on factors specific to individuals' primary non‐breeding sites, although proximity to aquaculture did not have biologically meaningful influences on black duck movement rates across all sites. Black ducks across sites consistently selected for areas better suited for aquaculture (i.e., areas of potential future development) relative to areas poorly suited for aquaculture (i.e., areas less likely to be developed). The continued expansion of aquaculture into preferred black duck habitats will increase black duck interactions with aquaculture and therefore should be considered in the decision‐making process for siting future aquaculture leases. Future studies should quantify the extent to which continued expansion of aquaculture in those preferred coastal habitats directly influences black ducks. [ABSTRACT FROM AUTHOR]

Aquaculture activities can affect water quality and phytoplankton composition. Our study estimated phytoplankton density and composition relating to aquaculture-impacted environmental factors. We analyzed water quality and phytoplankton at 35 sites in a tropical brackish lagoon, including inside aquaculture ponds (integrated farming of fish, shrimp, and crab), at wastewater discharge points, within 300 m of these points, and farther out in the lagoon. Measurements were taken after aquaculture activities started in March and again in July. In both periods, total nitrogen (TN), total phosphorus (TP), chlorophyll-a (Chl-a), and turbidity decreased from the aquaculture ponds to the farther lagoon areas. Principal component analysis showed that nutrients, turbidity, and Chl-a were critical factors in aquaculture ponds, while salinity, temperature, pH, dissolved oxygen (DO), and water depth influenced water quality outside the ponds. Phytoplankton density was higher in July than in March due to aquaculture characteristics. Redundancy analysis indicated that phytoplankton, typical of inorganic, turbid, shallow lakes, was present throughout, whereas marine phytoplankton characterized the open water area (OWA). Marine phytoplankton caused a higher Shannon–Wiener index in July compared to March for OWA. Phytoplankton in aquaculture ponds was dominated by Oscillatoria spp., while Thalassiosira spp. dominated outside the ponds. We also identified indicator genera for two connected lagoons. Although constant water exchange prevented identifying specific indicator phytoplankton groups for aquaculture, this revealed the impact of wastewater from aquaculture ponds on the natural environment in the lagoons. Research on phytoplankton communities is necessary for the sustainable development of aquaculture and environmental management in coastal lagoons. [ABSTRACT FROM AUTHOR]

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Aquaculture systems globally face significant environmental challenges, particularly concerning wastewater management. This review explores the innovative application of oxygenic photosynthetic microorganisms (OPhMs), specifically microalgae and cyanobacteria, as a sustainable solution for wastewater treatment within these systems. OPhMs offer a dual role in wastewater treatment by removing harmful pollutants such as nitrogen, phosphorus, and heavy metals, while simultaneously improving water quality through oxygenation. We evaluate the integration of OPhMs into existing aquaculture operations, considering key factors such as system design, operational conditions, and economic viability. Additionally, we discuss the potential of algal biomass as a secondary resource for producing biofuels, animal feed, and other bio-products, contributing to the circular economy model. Our findings highlight the ability of OPhM systems to significantly reduce the ecological footprint of aquaculture while recovering valuable resources. However, challenges such as process stability, especially under low-temperature conditions, and the efficiency of biomass harvesting, require further research. This study provides a comprehensive framework for future development and optimization of OPhM-based wastewater treatment systems to improve the sustainability of aquaculture operations. [ABSTRACT FROM AUTHOR]

Lake Maninjau, like many surface water bodies worldwide, faces significant water pollution challenges due to extensive aquaculture activities, making it an ideal site to study the impact of fish farming on water quality, which has contributed to eutrophication and declining water quality. This study investigates the physicochemical parameters and pollution levels in the lake, aiming to provide insights into its environmental health. In August 2022, a comprehensive sampling campaign was undertaken at nine stations within the upper layers of open water and littoral zones of Lake Maninjau. In situ measurements, including temperature, dissolved oxygen, and pH, were conducted, accompanied by water sample collection for laboratory analysis of trace elements and heavy metals. Our study revealed notable variability in water parameters across different sites, with surface water layers exhibiting the greatest differences. While certain parameters such as temperature and conductivity remain relatively stable, pH levels show a decreasing trend with increasing water depth. Dissolved oxygen levels vary widely, while oxidation–reduction potential indicates water pollution, particularly in littoral zones. Potassium dominance within cations likely suggests anthropogenic influences, notably from aquaculture activities, that may also contribute to nutrient enrichment and heavy metal pollution. Elevated levels of total nitrogen and ammonia underscore the lake's moderate pollution levels, with heavy metals such as mercury exceeding permissible limits, posing risks to aquatic life and human health. [ABSTRACT FROM AUTHOR]

Aquaculture stakeholders have mental models, which are the internal cognitive representations of how they understand and prioritize the different features of their aquaculture systems. Individuals and stakeholder groups are likely to have different mental models, with implications for making cooperative governance work and guiding the rapidly emerging sector's sustainable development. We apply a participatory approach called fuzzy cognitive mapping to capture and compare the mental models of community-based coastal pond aquaculture stakeholders in Indonesia, including farmers, government managers, and researchers who need to work together to govern a rapidly expanding aquaculture sector which faces critical sustainability challenges. To conceptually structure our comparison, we use Elinor Ostrom's social–ecological systems framework. Our results highlight important differences between stakeholder group mental models which represent potential conflicts of interest and barriers for collaborative governance. Fish farmer models emphasize resource system challenges relating to production instability and risk, while government managers emphasize increasing production intensity to meet sectoral growth targets. Researchers, in contrast, tend to focus on pond waste treatment and water quality management. Governance attributes were consistently perceived as less frequent and less influential compared to other social–ecological dimensions, reflecting perceptions of weak governance in the sector. We identify a critical need for programs aimed at strengthening community-level institutional arrangements for governing shared aquaculture resources, increasing technical knowledge capacity, and managing financial risk. By merging all stakeholder models into a single "community" model, we identify key consensus action situations across the three groups as potential focal points for aquaculture development which may serve as a starting point for actors to work together to identify context-appropriate institutional solutions to these sustainability challenges. [ABSTRACT FROM AUTHOR]

Introduction: Bivalve aquaculture has direct and indirect effects on plankton communities, which are highly sensitive to short-term (seasonal, interannual) and long-term climate changes, although how these dynamics alter aquaculture ecosystem interactions is poorly understood. Methods: We investigate seasonal patterns in plankton abundance and community structure spanning several size fractions from 0.2 µm up to 5 mm, in a deep aquaculture embayment in northeast Newfoundland, Canada. Results: Using flow cytometry and FlowCam imaging, we observed a clear seasonal relationship between fraction sizes driven by water column stratification (freshwater input, nutrient availability, light availability, water temperature). Plankton abundance decreased proportionally with increasing size fraction, aligning with size spectra theory. Within the bay, greater mesozooplankton abundance, and a greater relative abundance of copepods, was observed closest to the aquaculture lease. No significant spatial effect was observed for phytoplankton composition. Discussion: While the months of August to October showed statistically similar plankton composition and size distribution slopes (i.e., food chain efficiency) and could be used for interannual variability comparisons of plankton composition, sampling for longer periods could capture long-term phenological shifts in plankton abundance and composition. Conclusions provide guidance on optimal sampling to monitor and assess aquaculture pathways of effects. [ABSTRACT FROM AUTHOR]

Farmed aquaculture species play an important role in regulating nutrient cycles in farming systems. Compared with nitrogen and phosphorus, the role of farmed species in the silicon (Si) cycle remains poorly understood. To help reduce this uncertainty, we clarified the sources and sinks of silicate and quantified the Si pools in an aquaculture system in Sanggou Bay (SGB). The results showed that dissolved inorganic nutrient levels were significantly lower during the dry season than during the wet. Dissolved silicate (DSi) is a potential limiting factor for phytoplankton growth during spring, and phosphorus limitation occurs during summer. The budget results indicated that large amounts of nitrogen, phosphate (DIP), and DSi were buried in the sediment or transformed into other forms during both the wet and dry seasons. The nitrogen and DIP cycles were strongly influenced by bivalve excretion and farmed species harvesting; however, these processes had little impact on the Si cycle. Si availability depends on both external inputs and internal recycling. DSi was primarily supplied from the Yellow Sea, with a minor contribution from the river due to river discharge during spring. However, during summer, riverine inflow (accounting for 83% of the total influx) was the major DSi source followed by benthic flux (12%). Biogenic silica (BSi) burial efficiency in the sediment was estimated to be 78% during spring and 23% during summer. The BSi preservation efficiency in bivalves during spring was high (53%), leading to a higher Si retention than in river discharge. Bivalves biodeposition plays an important role in the Si burial process. We suggest that this high retention is essentially controlled by the biodeposition mechanism, which is directly controlled by the exotic suspension feeders. Bivalves have the potential to alter Si retention in the bay by producing large amounts of biodeposits and accelerating the silica cycle, which may lead to more carbon dioxide being absorbed by diatoms. [ABSTRACT FROM AUTHOR]

The editorial "Blue foods security and sustainability" discusses the importance of aquatic foods in global nutrition and food security, supporting over 3.2 billion people worldwide. Despite the significant growth in blue food production, persistent hunger remains a global issue, with 28.9% of the population food insecure in 2023. The editorial emphasizes the need for innovative practices and sustainable management to address ecological and environmental challenges, ensuring the continued contribution of blue foods to global food security and environmental resilience. [Extracted from the article]

Introduction: Piscirickettsia salmonis, the causative agent of Piscirickettsiosis, poses a significant threat to the Chilean aquaculture industry, resulting in substantial economic losses annually. The pathogen, first identified as specie in 1992, this pathogen was divided into two genogroups: LF-89 and EM-90, associated with different phenotypic mortality and pathogenicity. Traditional genotyping methods, such as multiplex PCR, are effective but limited by their cost, equipment requirements, and the need for specialized expertise. Methods: This study validates Loop-mediated Isothermal Amplification (LAMP) as a rapid and specific alternative for diagnosing P. salmonis infections. We developed the first qPCR and LAMP assay targeting the species-conserved tonB receptor gene (tonB-r, WP_016210144.1) for the specific species-level identification of P. salmonis. Additionally, we designed two genotyping LAMP assays to differentiate between the LF-89 and EM-90 genogroups, utilizing the unique coding sequences Nitronate monooxygenase (WP_144420689.1) for LF-89 and Acid phosphatase (WP_016210154.1) for EM-90. Results: The LAMP assays demonstrated sensitivity and specificity comparable to real-time PCR, with additional benefits including rapid results, lower costs, and simplified operation, making them particularly suitable for field use. Specificity was confirmed by testing against other salmonid pathogens, such as Renibacterium salmoninarum, Vibrio ordalii, Flavobacterium psychrophilum, Tenacibaculum maritimum, and Aeromonas salmonicida, with no cross-reactivity observed. Discussion: The visual detection method and precise differentiation between genogroups underscore LAMP's potential as a robust diagnostic tool for aquaculture. This advancement in the specie detection (qPCR and LAMP) and genotyping of P. salmonis represents a significant step forward in disease management within the aquaculture industry. The implementation of LAMP promises enhanced disease surveillance, early detection, and improved management strategies, ultimately benefiting the salmonid aquaculture sector. [ABSTRACT FROM AUTHOR]

In this paper, a biological aerated filter (BAF) based on ferromanganese oxide-biochar (FMBC) was constructed to investigated the removal performance and mechanism for conventional pollutants and four kinds of antibiotic, in contrast of conventional zeolite loaded BAF (BAF-A) and bamboo biochar filled BAF (BAF-B). Results showed that the average removal efficiency of total nitrogen (TN), total phosphorus (TP) and antibiotics in a FMBC-BAF (named by BAF-C) were 52.97 ± 2.27%, 51.58 ± 1.92% and 70.36 ± 1.00% ~ 81.65 ± 0.99% respectively in running period (39–100 d), which were significantly higher than those of BAF-A and BAF-B. In the BAF-C, the expression of denitrification enzyme activities and the secretion of extracellular polymeric substance (EPS) especially polyprotein (PN) were effectively stimulated, as well as accelerated electron transfer activity (ETSA) and lower electrochemical impedance spectroscopy (EIS) were acquired. After 100 days of operation, the abundance of nitrogen, phosphorus and antibiotic removal functional bacteria like Sphingorhabdus (4.52%), Bradyrhizobium (1.98%), Hyphomicrobium (2.49%), Ferruginibacter (7.80%), unclassified_f_Blastoca tellaceae (1.84%), norank_f_JG30-KF-CM45 (6.82%), norank_f_norank_o_SBR1031 (2.43%), Nitrospira (2.58%) norank_f_Caldilineaceae (1.53%) and Micropruina (1.11%) were enriched. Mechanism hypothesis of enhanced performances of nutrients and antibiotics removal pointed that: The phosphorus was removed by adsorption and precipitation, antibiotics removal was mainly achieved through the combined action of adsorption and biodegradation, while nitrogen removal was realized by biologic nitrification and denitrification in a FMBC-BAF for aquaculture wastewater treatment. [ABSTRACT FROM AUTHOR]

The pomfret fish, particularly the black pomfret (Parastromateus niger), serves as a significant economic resource in South Asia, particularly in the coastal regions of Balochistan, Pakistan. This study investigates various biological parameters of Parastromateus niger collected from the Gaddani coastal area of Pakistan, focusing on length-weight relationships, gut fullness, and population demographics. A total of 117 fish specimens were collected, with females dominating the samples. Length and weight data were analyzed separately for males and females, with statistical calculations revealing strong correlations (r2 values ranging from 0.918 to 0.985) between length and weight for both sexes. Gut fullness was categorized into five levels, with the highest percentage observed during July, suggesting potential breeding activity during this period. The zooplanktons were identified as primary dietary components of Parastromateus niger. The study also highlights the importance of regulatory measures to sustainably manage fish populations, especially during breeding seasons, and calls for further research into the intensive culturing and feeding regimes of black pomfret to enhance its production. Overall, these findings contribute to a better understanding of the biological characteristics and potential for aquaculture development of Parastromateus niger in the region. [ABSTRACT FROM AUTHOR]