Aquaculture Sector Research Articles

Aquaculture in Algeria: Current Status, Analysis, and Considerations for Commercial Development

Aquaculture in Algeria has developed significantly since the 1920s, primarily focusing on oyster and mussel farming. Establishing the Ministry of Fisheries and Marine Resources (MPRH) in 1999 marked a crucial milestone for the industry. Despite challenges in data collection, Algerian aquaculture production reached only 4,779.29 tonnes in 2021, showing a mere 0.2% of African production and 0.0044% of world aquaculture production. More than half of production comes from marine fish cultured in private-sector sea cages. However, shrimp production is almost null. The taxonomic composition of Algerian aquaculture is diverse, with marine and freshwater fish species playing prominent roles. Despite these challenges, the aquaculture field in Algeria has demonstrated an impressive annual growth rate of 12.49% and receives continuous government support. Nevertheless, limited infrastructure, a shortage of expertise, and the need for further research pose significant obstacles. Efforts are underway to integrate aquaculture with agriculture in Saharan zones, further facilitated by governmental support. Overcoming challenges and promoting sustainability through strengthening research capacities, fostering collaboration, and providing financial support is crucial for the advancement of industry. By addressing challenges and embracing sustainability, the aquaculture sector in Algeria can unlock its full potential, ensuring food security, economic growth, and environmental sustainability.

Technological innovation in fisheries and aquaculture: What are the “discourses” of the Italian policy network?

This paper aims to explore the point of view of experts of the Italian policy network of the fisheries and aquaculture sectors on technological innovation. This type of research is still very recent and unexplored, and it is important to stress that most studies have been conducted to primarily analyze the point of view of producers. Over the past decades, there has been a growing recognition that the adoption of new technological innovation in the fisheries and aquaculture sectors should consider the perspective of all the stakeholders acting on the captured or farmed resource. The perspective of the experts involved in the political processes, or, in other words, the view of the “policy network” remains a largely unexplored field of analysis which deserves much more attention. With this purpose, the Q methodology is highlighted as an effective strategy for examining the policy network’s perception toward technological innovation. The findings pointed out four macro discourses summarised in two main approaches to innovation: conservative, for which technological innovation is merely seen as a tool, the potential of which can be found in the perspective of improving a company’s management; and progressive, which recognizes a wider effectiveness of innovation, even outside the functional unit of the company. The results could provide new insights to understand the people-policy gap in blue sectors, prompting European policymakers to rethink existing policies to stimulate the diffusion of innovative technologies.

Innovative Thermal Renders Incorporating Oyster Shells for Sustainable Insulation

In accordance with current sustainable development objectives, it is intended to implement innovative and sustainable solutions at economic, environmental, and functional levels, boosting the construction sector to increasingly contribute to society. Expanded cork is an alternative to sand aggregate in improving the thermal insulating properties of renders. In addition, other materials can be incorporated as aggregates in an attempt to contribute to both the improvement of the physical characteristics that the render must fulfil as well as the improvement of thermal behaviour (if possible). In this sense, bio-based materials generated by the aquaculture sector, such as oyster shells, can contribute as a bio-based insulation material for thermal renders. In this study, thermal natural hydraulic lime mortars were produced from a mixture of expanded cork (EC) insulating aggregate and oyster shells (OSs). The percentages of replacing EC by OSs were 20, 30, 40, and 50%. The tests were carried out in fresh and hardened states. The studied mortars presented a thermal conductivity and compressive strength of 0.151 W/(m·K) and 0.63 MPa, respectively. The most interesting performance between thermal conductivity and compressive strength was for the composite with 50% of each bio-based material. The potential of incorporating oyster shells as a bio-based insulation material could contribute to a sustainable blue circular economy.

Growth Performance and Biochemical Composition of Nile Tilapia (Oreochromis niloticus) Reared in Membrane Bioreactor Treated Wastewater

The aquaculture sector in Africa has great potential for growth; however, it faces several challenges, one of them being the scarcity of clean water. This prompts the need for water recycling. The present study was conducted to investigate the effects of rearing Nile tilapia (Oreochromis niloticus) using municipal wastewater treated with membrane bioreactor (MBR) technology. A total of 270 Nile tilapia fingerlings (0.15±0.05 g) were reared in three treatment groups in triplicate. There were 2 treatments, including; MBR treated wastewater and stabilization pond treated wastewater (maturation pond), while the municipal tap water was used as the control. The growth performance (weight and length) of the fish was monitored over a 24-week period. After the experimental period, the biochemical composition of the fish muscle was analysed using standard AOAC methods. The results showed that the highest weight gain, length gain, survival rate, and specific growth were obtained in the fish in the control followed by the MBR treatment. Additionally, the crude protein, as well as the crude fiber and dry matter, were significantly higher in the fish in the maturation ponds at 23.10%, 0.29%, and 25.35%, respectively, while the crude ash was highest in the MBR at 1.22%. Results also showed that the MBR and maturation pond treatments meet the permissible levels for BOD, COD, NH4, and NO3 for water to be used in aquaculture. The bioaccumulation of heavy metals in the fish was mainly from the feed, with copper being the highest contaminant at 1.75 mg/100 g. In conclusion, both the MBR and maturation pond treated wastewater are viable for use in the rearing of Nile tilapia without adverse effect on the growth. However, MBR treatment showed better growth performance, suggesting that it could be used to increase productivity in fish farming.

Comparative study of the programs and actions on fisheries and aquaculture, based on three PPAS in the state of Pará

The present study analyzed the scarce data available to date from the fishing and aquaculture sectors in the twelve Integration Regions of the state of Pará, which may serve in the future as a subsidy for the development of public policies for sustainable growth, management and administration of fishing and aquaculture. This scientific contribution analyzed the main State Government Programs included in the Multi-Year Plans that cover Fisheries and Aquaculture from 2013 to 2022, contextualizing their respective Actions (planned and carried out) with the Federal and State Laws, which deal respectively with the National Policy for Sustainable Development of Aquaculture and Fisheries and Fisheries and Aquaculture Policy in the state of Pará.

ECOPHAGE: Combating Antimicrobial Resistance Using Bacteriophages for Eco-Sustainable Agriculture and Food Systems.

The focus of this meeting was to discuss the suitability of using bacteriophages as alternative antimicrobials in the agrifood sector. Following a One Health approach, the workshop explored the possibilities of implementing phage application strategies in the agriculture, animal husbandry, aquaculture, and food production sectors. Therefore, the meeting had gathered phage researchers, representatives of the agrifood industry, and policymakers to debate the advantages and potential shortcomings of using bacteriophages as alternatives to traditional antimicrobials and chemical pesticides. Industry delegates showed the latest objectives and demands from consumers. Representatives of regulatory agencies (European Medicines Agency (EMA) and Spanish Agency of Medicines and Health Products (AEMPS)) presented an update of new regulatory aspects that will impact and support the approval and implementation of phage application strategies across the different sectors.

Species Selection for Profitable Commercial Fish Culture Through Biofloc Technology

Biofloc technology is a recent concept in Bangladesh, it has numerous advantages for enhancing aquaculture production in several countries, thereby contributing to achieve sustainable development goals. To identify the most suitable fish species for profitable commercial fish culture through Biofloc, a 100-day experiment was conducted at Pran Fisheries Project in Razapur Village, situated in Sreemangal Upazilla of Moulvibazar district, commencing in March 2021. The experiment comprised three treatments: Oreochromis niloticus, Anabus testudineus, and Labeo rohita with two replicates for each treatment. Water quality parameters were meticulously monitored to ensure optimal conditions. All treatments were conducted at a temperature of 26°C, with pH levels of 7.6-7.8, dissolved oxygen concentrations of 5-6 ppm. During the study, O. niloticus exhibited the highest body weight (66.23 ± 0.94) compared to A. testudineus (50.82 ± 0.94) and L. rohita (53.92 ± 0.17). Furthermore, L. rohita displayed a higher average daily weight gain (1.8 ± 0.003) and specific growth rate (3.29 ± 0.29). The best feed conversion ratio (FCR) was observed both for O. niloticus (0.98 ± 0.33) and A. testudineus (0.98 ± 0.03). In terms of survival rate, O. niloticus outperformed the other species, with a rate of 98%. However, O. niloticus demonstrated better aquaculture performance compared to the other species using biofloc technology. This research provides valuable insights in effective cultural techniques that can enhance fish production through biofloc technology, contributing to economic growth in aquaculture sector and national development. J. Bio-Sci. 31(1): 71-85, 2023

A SWOT Analysis of Aquaculture for Sustainable Management in Coastal Waters of Ba Ria – Vung Tau Province, Vietnam

Aquaculture stands as a vital marine economic sector in Vietnam's coastal provinces, with specific significance in Ba Ria - Vung Tau. The steady growth of this sector plays a pivotal role in local socio-economic development. However, this growth has led to legitimate concerns about environmental sustainability and socio-economic progress. Building on the findings from sociological surveys conducted through questionnaires and comprehensive interviews in 2022, this article has applied the Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis method to pinpoint the existing issues that need attention in the aquaculture sector. Moreover, this study proposes strategies and guidelines for aquaculture development in a manner that ensures responsible environmental management while balancing economic growth with societal well-being. The aquaculture industry in Ba Ria-Vung Tau is presented with numerous growth opportunities, driven by the rising consumer demand for seafood consumption, ongoing technological advancements, and the pursuit of sustainable development goals. Yet, it has to navigate challenges such as resource scarcity, market competition, regulatory constraints, and the perpetual threats of climate change and disease. The industry's advancement is contingent on the collaboration of stakeholders to leverage strengths, address weaknesses, seize opportunities, and confront threats, all while minimizing adverse impacts on nature, ecosystems, and socio-economic aspects. To secure long-term sustainability, the industry must embrace prudent management practices, foster innovation, encourage collaboration, and proactively tackle these challenges. This work underscores the multifaceted nature of sustainable aquaculture and underscores the indispensable role of informed, forward-thinking management in ensuring its enduring viability.

Potential Role of Plant Polysaccharides as Immunostimulants in Aquaculture – A Review

Abstract Aquaculture is one of the primary food-producing sectors in the world that ensures human nourishment. However, aqua farmers are facing serious problems due to disease outbreaks and development of antimicrobial resistance. Until now, chemical or antibiotic based strategies have been applied to control disease related concern in aquaculture. Frequent usage of antibiotics in feed or usage of disinfectant to overcome the disease may end up with negative impacts to the environment and human. Utilization of plant derived polysaccharides has been drastically increased due to their effective roles and could serve as a best replacement for chemical agents and antibiotics. In addition, plant derived compounds and plant extracts were utilized to improve the immunity, intestinal health and growth performance of aquaculturable organisms. In addition, large number of plant-based polysaccharides was utilized as immunostimulants in aquaculture. Hence, this review aims to highlight the multifunctional properties of plant-based polysaccharides in aquaculture. Moreover, advantages and different concentration of plant polysaccharides as a feed additive in aquaculture sector have been discussed herein.

Resource-process approach to the aquaculture industry development

Aquaculture is one of the most promising industries in the world. The relevance of the research topic is due to the fact that in order to effectively use the potential of this industry, the organizational and economic mechanisms for ensuring business processes in fish farming developed by world practice were studied. Business processes are considered in general for aquaculture. During the research, a resource-process matrix was developed for the aquaculture sector. The result of the study is the identified mechanisms for ensuring business processes in aquaculture, which can help improve the situation of this industry in Ukraine. As a conclusion, the relevance of applying an integrated approach based on business processes along the value chain in combination with resource provision is determined. Also, the research proposes organizational and economic mechanisms for the development of each link of the matrix "resources-processes" of the chain of value creation in the aquaculture sector.

Understanding the effect of design parameters on the filtration efficiency of trawls intended for commercial harvesting of zooplankton

A major challenge for the aquaculture sector is access to sustainable and cost-effective raw materials for feed. Copepods (Calanus spp.) have potential to meet this need for large volumes of marine raw materials to enable sustainable growth of aquaculture production worldwide. However, the lack of an energy- and catch-efficient trawl technology has limited the development of this fishery in the Northeast Atlantic. Therefore, the goal of this study was to develop a next generation trawl for harvesting zooplankton that was less energy demanding and more catch efficient than current trawl designs. We assessed the filtration efficiency of low porosity nets with different solidities and studied the effects of design parameters (mesh opening, twine thickness, porosity, taper angle) at various flow velocities in a flume tank. We found that the filtration efficiency for a square meshed net increased with increasing velocity and decreasing solidity and taper angle. A large open area ratio (the ratio between the open netting area and the net's mouth area) improved the filtration efficiency at towing velocities below 0.5 ms−1. These results provided an indication of the initial filtration efficiency of the net designs (i.e., before any clogging occurs) but not of the sustained filtration efficiency.

The Role of Shrimp Breeding Innovation in Improving Aquaculture Productivity and Fisheries Business Sustainability in Sumbawa, West Nusa Tenggara

The aquaculture sector has come to be recognized as a key engine of both economic growth and seafood production worldwide. Shrimp farming in particular, and aquaculture in general, are major contributors to local livelihoods and food security in Sumbawa, West Nusa Tenggara, Indonesia. However, as this industry expands, it will have to contend with issues pertaining to productivity, sustainability of the environment, and the long-term viability of the fishing industry. Innovations in shrimp breeding have been implemented in the area to solve these problems. The various effects of these advances on aquaculture productivity and the long-term viability of Sumbawa's fishing enterprises are examined in this qualitative investigation. The results show how innovation, productivity, sustainability, and the particular socio-environmental setting of the area interact in a complicated way. Shrimp growth and disease resistance have increased thanks to selective breeding techniques, but genetic manipulation is still up for discussion. Sustainable feed methods are a viable way to lessen the impact on the environment. Effective disease management, together with market access and adherence to international quality standards, are critical components of a sustainable fisheries enterprise. This study promotes sustainable aquaculture methods and the long-term success of Sumbawa's fishing enterprises by offering useful insights and suggestions.

Molecular fingerprint of gilthead seabream physiology in response to pollutant mixtures in the wild

The increase in trace element concentrations in the aquatic environment due to anthropogenic activities, urges the need for their monitoring and potential toxicity, persistence, bioaccumulation, and biomagnification at different trophic levels. Gilthead seabream is a species of commercial importance in the Mediterranean Sea, both for the aquaculture and fisheries sectors, however very little is known about their trace element contamination accumulation and the resulting effect on their health status. In the present study, 135 juveniles were collected from seven coastal lagoons known to be essential nursery areas for this species. We measured seventeen different inorganic contaminants at the individual level in fish muscle (namely Al, As, Be, Bi, Cd, Cr, Cu, Hg, Li, Ni, Pb, Rb, Sb, Sr, Ti, Tl and Zn). Our results revealed the accumulation of multiple trace elements in individuals and distinct contamination signatures between lagoons which might lead to contrasted quality as nurseries for juveniles of numerous ecologically and economically relevant fish species in addition to seabreams. We further evaluated the potential adverse effect of these complex contamination mixtures on the liver (the main organ implicated in the metabolism of xenobiotics) and red muscle (a highly metabolic organ) using a proteomic approach. Alterations in cellular organization pathways and protein transport were detected in both tissues (albeit they were not similarly regulated). Chromosome organization and telomere maintenance in the liver appeared to be affected by contaminant mixture which could increase mortality, age-related disease risk and shorter lifetime expectancy for these juveniles. Red muscle proteome also demonstrated an upregulation of pathways involved in metabolism in response to contamination which raises the issue of potential energy allocation trade-offs between the organisms’ main functions such as reproduction and growth. This study provides new insights into the cellular and molecular responses of seabreams to environmental pollution and proposed biomarkers of health effects of trace elements that could serve as a starting point for larger-scale biomonitoring programs.

The Application of Synthetic Flavors in Zebrafish (Danio rerio) Rearing with Emphasis on Attractive Ones: Effects on Fish Development, Welfare, and Appetite.

The aim of the present study was to test synthetic flavors as potential feed attractants in zebrafish (Danio rerio) during early development. Six experimental groups were set up in triplicate: (i) a CTRL group fed a zebrafish commercial diet; (ii) a PG group fed a control diet added with Propylene Glycol (PG); (iii) A1+ and A2+ groups fed a control diet added with 1% of the two attractive flavors (A1+ cheese odor made by mixing Propylene Glycol (PG) with the aromatic chemicals trimethyamine, 2-acetylpyrazine, 2-acetylpyridine, and dimethyl sulfide; and A2+ caramel odor, made of PG mixed with the aromatic chemicals vanillin, maltol, cyclotene, acetoin, butyric acid, and capric acid with traces of both gamma-octalactone and gamma-esalactone) or the repulsive flavor (A- coconut odor, made by mixing PG with the aromatic chemicals gamma-eptalactone, gamma-nonalactone, delta-esalactone, and vanillin with trace of both delta-octalactone and maltol), respectively; (iv) an ROT group fed the two attractive diets, each administered singularly in a weekly rotation scheme. All the tested synthetic flavors did not affect the overall health of larval and juvenile fish and promoted growth. Due to the longer exposure time, results obtained from the juvenile stage provided a clearer picture of the fish responses: zebrafish fed both attractive diets showed higher appetite stimulus, feed ingestion, and growth, while the brain dopaminergic activity suggested the A2+ diet as the most valuable solution for its long-lasting effect over the whole experiment (60-day feeding trial, from larvae to adults). The present study provided important results about the possible use of attractive synthetic flavors for aquafeed production, opening new sustainable and more economically valuable opportunities for the aquaculture sector.

Antibacterial protein fraction derived from Streptomyces fradiae against septicemia infection in Labeorohita: Breakthrough in marine drug discovery

The aquaculture sector continues to be an essential source of food, revenue, nutrition, and a means of subsistence for numerous people globally. Intensive aquaculture in a confined region induces environmental stress in farmed fish, which indirectly increases their vulnerability to many diseases. Aeromonas hydrophila, Pseudomonas aeruginosa, and Vibrio harveyi are the causative bacterial pathogens for septicemia, the most prevalent and commonly seen illness. Disease outbreaks result in a rise in mortality or a decrease in the quality of the meat, consequently inflicting substantial economic losses to carp production. In contrast, the continual use of antibiotics for infection management has contributed to the proliferation of drug-resistant bacteria in aquatic environments. In this context, marine actinobacteria are emerging as possible sources of new secondary metabolites to combat the problem. Actinobacteria are undoubtedly the most prolific producers of secondary metabolites, and they comprise several commercially and biotechnologically significant species. In this investigation, marine actinobacteria were isolated and evaluated for their antibacterial effectiveness against septicemia pathogens. Effective strains were identified as Nocardiopsis sp., Streptomyces sp., and Pseudonocardia sp. Candidate strains culture filtrates were treated with acetone to precipitate complete proteins. The antibacterial and anti-quorum sensing properties of the crude protein against A. hydrophila MTCC 1739 and P. aeruginosa MTCC 9425 were also examined using the agar well diffusion method. In addition, in vivo investigations of the low molecular weight fraction on Labeorohita demonstrated the fraction's efficacy in reducing septicemia infection. After the 8th day of bathing, fish were found to have recovered.

The role of Aeromonas genotyping in virulence for Dicentrarchus labrax.

Aeromonas septicemia still represents a serious challenge facing the global aquaculture sector. In the present study, Aeromonas caviae and A. veronii were isolated from four diseased European seabass (Dicentrarchus labrax) farms experiencing a high mortality rate. Diseased fish showed haemorrhages on the external body surface with exophthalmia, cataracts, scale desquamation, skin ulcers and fin erosions. The most common post-mortem findings were congested internal organs, particularly the liver and posterior kidney. Twenty-eight A. Veronii and 11 A. caviae isolates were identified biochemically by the Vitek 2 system and then confirmed by PCR and phylogenetic analysis. Hemolysin (hlyA) and aerolysin (aer) were the most abundant virulence genes in the recovered isolates, followed by cytotoxic enterotoxin (act) and heat-stable enterotoxin (ast). A. caviae was more virulent than A. veronii for D. labrax fingerlings as LD50 ranging between (>1 × 108 -6.2 × 107 ) for A. veronii and (2.9 × 107 -8.3 × 107 ) for A. caviae. The sensitivity test indicated the effectiveness of norfloxacin, doxycycline and oxytetracycline against the tested isolates. Serum cortisol significantly increased in the infected groups, while catalase and glutathione peroxidase activities significantly decreased at 2 days post-infection (DPI) and then increased at 6 DPI. The presence of virulence genes was associated with bacterial pathogenicity expressed in fish mortality rate. Virulence genes also drastically affect cortisol levels more than catalase and glutathione peroxidase levels.

Growth performance and physiological responses of striped catfish (Pangasianodon hypophthalmus) under different carbohydrates supplemented biofloc aquaculture systems

Biofloc technology is booming in inland aquaculture sector across the world especially in the places where water scarcity is high and land cost is expensive. Currently, the lack of appropriate selection and application feasibility of suitable carbohydrate in water quality management and fish health in biofloc aquaculture system are the major concern for wider adaptability of the technology. Therefore, the present experiment investigated the effect of different carbohydrate sources on overall wellbeing of striped catfish (Pangasianodon hypophthalmus) fingerlings. The experiment was randomly designed in four treatments (T1, T2, T3 and T4) and one control in triplicates in indoor tanks (1.0 m3). T1, T2, T3 and T4 groups supplemented with tapioca flour, sugarcane bagasse, molasses and jaggery, respectively under biofloc system at C:N ratio of 15:1, whereas the control group was not supplemented with carbohydrate source. Pre-acclimatized 525 fingerlings (7.2 ± 0.03 cm, 7.4 ± 0.003 g) were randomly stocked (35 nos. m−3) in the tanks and reared for 90 days. Overall, better water quality, fish performance and health status were observed in all the carbohydrates supplemented treatments than the control. Higher abundance of heterotrophic bacteria (5.88–118.18%) and biofloc associated microorganisms in jaggery supplemented biofloc, significantly (P ≤ 0.05) reduced total ammonia nitrogen, nitrite‑nitrogen, and increased nitrate‑nitrogen concentrations than other treatments. In the T4 treatment, jaggery supplementation enhanced biofloc volume, which influenced enhancement of fish body weight gain, specific growth rate, and improvement of feed conversion ratio than other biofloc treatments. Enhanced gut microbial population and digestive enzymes activity in fish significantly enhanced protein efficiency ratio, apparent net protein utilization, and flesh protein content in the T4 treatment. Fish showed significantly (P ≤ 0.05) higher haematological, immunological, and improved antioxidative responses in the T4 treatment than other treatments. Consumption of biofloc significantly (P ≤ 0.05) improved intestinal villi microarchitecture as higher villi surface area, width and height were detected in the T4 treatment. Collectively, the findings suggested that jaggery was the suitable carbohydrate source in terms of overall improvement of the culture system including growth performance and health status of P. hypophthalmus, if applied appropriately in biofloc aquaculture system. The present study comprehensively addressed carbohydrate sources, biofloc formation, total ammonia nitrogen management, fish growth and health resulting in better adoptability of biofloc technology by farmers in aquaculture.

Widespread dominance of methane ebullition over diffusion in freshwater aquaculture ponds

An ever-increasing demand for protein-rich food sources combined with dwindling wild fish stocks has caused the aquaculture sector to boom in the last two decades. Although fishponds are potentially strong emitters of the greenhouse gas methane (CH4), little is known about the magnitude, pathways, and drivers of these emissions. We measured diffusive CH4 emissions at the margin and in the center of 52 freshwater fishponds in Brazil. In a subset of ponds (n = 31) we additionally quantified ebullitive CH4 fluxes and sampled water and sediment for biogeochemical analyses. Sediments (n = 20) were incubated to quantify potential CH4 production. Ebullitive CH4 emissions ranged between 0 and 477 mg m−2 d−1 and contributed substantially (median 85%) to total CH4 emissions, surpassing diffusive emissions in 81% of ponds. Diffusive CH4 emissions were higher in the center (median 11.4 mg CH4 m−2 d−1) than at the margin (median 6.1 mg CH4 m−2 d−1) in 90% of ponds. Sediment CH4 production ranged between 0 and 3.17 mg CH4 g C−1 d−1. We found no relation between sediment CH4 production and in situ emissions. Our findings suggest that dominance of CH4 ebullition over diffusion is widespread across aquaculture ponds. Management practices to minimize the carbon footprint of aquaculture production should focus on reducing sediment accumulation and CH4 ebullition.

The fatty acid composition of black soldier fly larvae: the influence of feed substrate and applications in the feed industry

Abstract The need to reduce, reuse and recycle materials by applying new strategies of circular economy instead of linear systems of disposal is becoming increasingly urgent. The black soldier fly (BSF), Hermetia illucens (L.) (Diptera: Stratiomyidae), is being studied for its outstanding capacity to convert organic waste into high-value biomass and as a valuable nutrient source for animal feed. A systematic literature review identified 35 articles on BSF rearing and use in animal feed. This review summarizes our current knowledge about the lipid composition of BSF larvae, in particular their fatty acid (FA) profile and the mechanisms through which the feeding substrate influences the FA profile. BSF larvae are shown to synthesize certain FAs, such as lauric and myristic acid, even when these components are absent from their diet. Furthermore, enriching the rearing substrate with eicosapentaenoic and docosahexaenoic acid is reported to increase the accumulation of these FAs. The saturated FA content increases when BSF larvae are reared on a vegetable-based diet. Moreover, enriching the rearing media with materials high in omega-3 and omega-6 FAs increases their concentration in the larvae and enhances their value as a feed substrate for other animals. Indeed, the supplementation of animal feeds with BSF larvae products is being studied for application in the aquaculture, poultry, and pig farming sectors. BSF larval fats are shown to have a positive effect on animal growth performances, body composition, and gut histology, establishing BSF larvae as an environmentally-sustainable feed ingredient. This review highlights the importance of deepening our knowledge on the various aspects of BSF larvae rearing and treatments which enhance the accumulation of specific lipids and minimize lipid quality deterioration and loss. By summarizing the existing literature on BSF larvae, this article contributes to the advancement of circular economies and the development of sustainable feed practices.

Synthesis and characterization of gold nanoparticles using Brevibacterium casei (SOSIST-06) isolated from Southern Ocean water samples and their in vitro and in silico anti-WSSV activity

The worldwide shrimp aquaculture business, which is expanding and producing food, has experienced significant economic losses due to a variety of disease outbreaks. One of the main viral pathogens for the global shrimp aquaculture sector is the white spot syndrome virus (WSSV). There have been several attempts to eradicate the virus in shrimp, but none of them have been successful in the long-term effectiveness. In the present work, we establish the isolated strain identified as Brevibacterium casei SOSIST-06 from the Southern Ocean water sample and its capacity for green synthesis of gold nanoparticles. The nanoparticles were characterized using UV–vis spectroscopy, X-ray diffraction, and Transmission electron microscopy. The morphology of nanoparticles is most spherical and there are a few triangles with an average size ranging from 9.5 to 52.3 nm. In vitro anti-wssv activity was carried out using hybrid cell line PmLyo-Sf9 cells, and the synthesized gold nanoparticles were shown to inhibit the virus infection (attachment inhibitory and virucidal activity) with a dose-dependent effect. Further, the interaction of gold nanoparticles and VP28 envelope protein was confirmed using in silico approach. To our knowledge, this is the first study to identify that an actinobacterium, Brevibacterium casei synthesized gold nanoparticles could fight against the white spot syndrome virus. These findings do point the way towards creating potent antiviral or therapeutic techniques for aquaculture that utilize gold nanoparticles.