Contemporary aquaculture: implications for human nutrition

Differential Modulation by Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) of Mesenteric Fat and Macrophages and T Cells in Adipose Tissue of Obese fa/fa Zucker Rats

Polyunsaturated fatty acids (PUFAs) can alter adipose tissue function; however, the relative effects of plant and marine n3-PUFAs are less clear. Our objective was to directly compare the n3-PUFAs, plant-based α-linolenic acid (ALA) in flaxseed oil, and marine-based eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) in high-purity oils versus n6-PUFA containing linoleic acid (LA) for their effects on the adipose tissue and oral glucose tolerance of obese rats. Male fa/fa Zucker rats were assigned to faALA, faEPA, faDHA, and faLA groups and compared to baseline fa/fa rats (faBASE) and lean Zucker rats (lnLA). After 8 weeks, faEPA and faDHA had 11-14% lower body weight than faLA. The oral glucose tolerance and total body fat were unchanged, but faEPA had less mesenteric fat. faEPA and faDHA had fewer large adipocytes compared to faLA and faALA. EPA reduced macrophages in the adipose tissue of fa/fa rats compared to ALA and DHA, while faLA had the greatest macrophage infiltration. DHA decreased (~10-fold) T-cell infiltration compared to faBASE and faEPA, whereas faALA and faLA had an ~40% increase. The n3-PUFA diets attenuated tumour necrosis factor-α in adipose tissue compared to faBASE, while it was increased by LA in both genotypes. In conclusion, EPA and DHA target different aspects of inflammation in adipose tissue.

Substitution of fishmeal: Highlights of potential plant protein sources for aquaculture sustainability

High protein content, excellent amino acid profile, absence of anti-nutritional factors (ANFs), high digestibility and good palatability of fishmeal (FM), make it a major source of protein in aquaculture. Naturally derived FM is at risk due to an increase in its demand, unsustainable practices, and price. Thus, there is an urgent need to find affordable and suitable protein sources to replace FM. Plant protein sources are suitable due to their widespread availability and low cost. However, they contained certain ANFs, deficiency of some amino acids, low nutrient bioavailability and poor digestibility due to presence of starch and fiber. These unfavourable characteristics make them less suitable for feed as compared to FM. Thus, these potential challenges and limitations associated with various plant proteins have to be overcome by using different methods, i.e. enzymatic pretreatments, solvent extraction, heat treatments and fermentation, that are discussed briefly in this review. This review assessed the impacts of plant products on growth performance, body composition, flesh quality, changes in metabolic activities and immune response of fishes. To minimize the negative effects and to enhance nutritional value of plant products, beneficial functional additives such as citric acid, phytase and probiotics could be incorporated into the plant-based FM. Interestingly, these additives improve growth of fishes by increasing digestibility and nutrient utilization of plant based feeds. Overall, this review demonstrated that the substitution of fishmeal by plant protein sources is a plausible, technically-viable and practical option for sustainable aquaculture feed production.

Granulicatella seriolae sp. nov., a Novel Facultative Anaerobe Isolated from Yellowtail Marine Fish

A bacterial strain, designated as S8T, was isolated from the gut contents of Seriola quinqueradiata from the coastal sea area of Jeju Island, South Korea. The strain is a Gram-staining positive, non-motile, non-spore-forming, facultative anaerobic coccus. Optimal growth was observed at 30 °C, pH 8.0-9.0, and 0-0.5% w/v NaCl, under anaerobic conditions. The predominant fatty acids were C18:1 ω9c, C16:0, C18:0, and C16:1 ω9c, while quinone was not detected. The genome was 2,224,566 bp long, with a GC content of 38.2%. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain S8T had 96.2% similarity with Granulicatella adiacens ATCC 49175T, its closest known species according to nomenclature. The DNA-DNA hybridization (dDDH), average nucleotide identity, and average amino acid identity values between strain S8T and G. adiacens ATCC 49175T were 25.7%, 85.5%, and 77.2%, respectively, all of which fall below the recommended threshold for species differentiation. Based on genomic, phenotypic, and phylogenetic evidence, we propose that strain S8T should be a novel species within the genus Granulicatella, for with the name Granulicatella seriolae sp. nov. is proposed. The type strain is S8T (KCTC 43438T = JCM 35604T).

Ferulic acid alleviates carp brain damage and growth inhibition caused by avermectin by modulating the Nrf2/Keap1 and NF-κB signaling pathways

The increasing concern over environmental pollution caused by the pesticide avermectin used in aquaculture has attracted significant attention. The use of avermectin, a neurotoxic pesticide, in aquatic environments leads to toxic effects on non-target organisms, particularly causing harm to fish. The phenolic compound ferulic acid possesses excellent anti-inflammatory and antioxidant capabilities. This study was conducted by establishing a chronic exposure experiment to avermectin, proposes the use of ferulic acid as a dietary additive to protect the carp brain from damage caused by exposure to avermectin. Furthermore, it investigates the anti-inflammatory and antioxidant effects of ferulic acid in the carp brain under chronic exposure to avermectin. The experimental results demonstrate that ferulic acid can alleviate brain tissue inflammation and oxidative stress by modulating the Nrf2/Keap1 and NF-κB signaling pathways. It protects the carp brain from chronic avermectin-induced damage, preserves the integrity of the carp blood-brain barrier, enhances the levels of feeding factors, and thereby alleviates carp growth inhibition. These findings provide new therapeutic strategies and a theoretical foundation for the sustainable development of carp aquaculture.

Advances on genomes studies of large DNA viruses in aquaculture: A minireview

Genomic studies of viral diseases in aquaculture have received more and more attention with the growth of the aquaculture industry, especially the emerging and re-emerging viruses whose genome could contain recombination, mutation, insertion, and so on, and may lead to more severe diseases and more widespread infections in aquaculture animals. The present review is focused on aquaculture viruses, which is belonged to two clades, Varidnaviria and Duplodnaviria, and one class Naldaviricetes, and respectively three families: Iridoviridae (ranaviruses), Alloherpesviridae (fish herpesviruses), and Nimaviridae (whispoviruses). The viruses possessed DNA genomes nearly or larger than 100 kbp with gene numbers more than 100 and were considered large DNA viruses. Genome analysis and experimental investigation have identified several genes involved in genome replication, transcription, and virus-host interactions. In addition, some genes involved in virus genetic variation or specificity were also discussed. A summary of these advances would provide reference to future discovery and research on emerging or re-emerging aquaculture viruses.

Climate change exacerbates nutrient disparities from seafood

Seafood is an important source of bioavailable micronutrients supporting human health, yet it is unclear how micronutrient production has changed in the past or how climate change will influence its availability. Here combining reconstructed fisheries databases and predictive models, we assess nutrient availability from fisheries and mariculture in the past and project their futures under climate change. Since the 1990s, availabilities of iron, calcium and omega-3 from seafood for direct human consumption have increased but stagnated for protein. Under climate change, nutrient availability is projected to decrease disproportionately in tropical low-income countries that are already highly dependent on seafood-derived nutrients. At 4 oC of warming, nutrient availability is projected to decline by ~30% by 2100 in low income countries, while at 1.5-2.0 oC warming, decreases are projected to be ~10%. We demonstrate the importance of effective mitigation to support nutritional security of vulnerable nations and global health equity.

Inhibition of the NF-κB signaling pathway affects gonadal differentiation and leads to male bias in Paramisgurnus dabryanus

In recent years, sex-controlled breeding has emerged as an effective strategy to enhance the yields of economic animals with different growth characteristics, while increasing the economic benefits of aquaculture. It is known that the NF-κB pathway participates in gonadal differentiation and reproduction. Therefore, we used the large-scale loach as a research model for the present study and selected an effective inhibitor of the NF-κB signaling pathway (QNZ). This, to investigates the impacts of the NF-κB signaling pathway on gonadal differentiation during a critical period of gonad development and after maturation. Simultaneously, the sex ratio bias and the reproductive capacities of adult fish were analyzed. Our results indicated that the inhibition of the NF-κB signaling pathway influenced the expression of genes related to gonad development, regulated the gene expression related to the brain-gonad-liver axis of juvenile loaches, and finally impacted the gonadal differentiation of the large-scale loach and promoted a male-biased sex ratio. Meanwhile, high QNZ concentrations affected the reproductive abilities of adult loaches and inhibited the growth performance of offspring. Thus, our results deepened the exploration of sex control in fish and provided a certain research basis for the sustainable development of the aquaculture industry.

Occurrence, distribution, and ecological risks of antibiotics in Honghu Lake and surrounding aquaculture ponds, China

Antibiotics are largely applied in aquaculture to increase production and control diseases, while how the antibiotics used in pond farming influence the distribution of antibiotics in receiving water seasonally is still not well understood. In this study, the variations of 15 frequently used antibiotics in Honghu Lake and surrounding ponds were investigated seasonally to figure out the impact of pond farming on antibiotics distributions in Honghu Lake. Results showed that the antibiotic concentrations in fish ponds ranged from 11.76 to 389.8 ng/L, while in crab and crayfish ponds were lower than 30.49 ng/L. The predominant antibiotic in fish ponds was florfenicol, followed by sulfonamides and quinolones, with generally low concentrations. Sulfonamides and florfenicol were the main antibiotics in Honghu Lake, affected by the surrounding aquaculture water partially. The antibiotics residue in aquaculture ponds showed obvious seasonal characteristics, with the lowest in spring. From summer, the concentrations of antibiotics in aquaculture ponds gradually increased and reached a peak in autumn, and the seasonal variation of antibiotics in the receiving lake was also related to the antibiotics in the aquaculture ponds. Risk assessment analysis showed that antibiotics such as enrofloxacin and florfenicol in fish ponds posed a medium and low risk to algae, and Honghu Lake acted as a natural reservoir of antibiotics and poses increased risks to algae. In general, our study demonstrated that aquaculture represented by pond farming brought significant risks of antibiotic pollution to natural water bodies. Therefore, reasonable control of the fish antibiotics usage in autumn and winter, as well as the rational use of antibiotics in aquaculture and the use of antibiotics before pond cleaning, is required to reduce the migration of antibiotics from aquaculture surface water to the receiving lake.

Transcriptomic and metabolomic insights into the role of the flgK gene in the pathogenicity of Pseudomonas plecoglossicida to orange-spotted grouper (Epinephelus coioides)

Pseudomonas plecoglossicida is the pathogen responsible for visceral white spot disease in large yellow croaker (Larimichthys crocea) and orange-spotted grouper (Epinephelus coioides). Previously, RNA sequencing showed that P. plecoglossicida flgK gene expression was significantly up-regulated in orange-spotted grouper spleens during infection. To explore the role of flgK in P. plecoglossicida pathogenicity, RNA interference (RNAi) was performed to silence the P. plecoglossicida flgK gene, and the mutant (flgK-RNAi strain) with the best silencing efficiency (89.40%) was chosen for further study. Results showed that flgK gene silencing significantly attenuated P. plecoglossicida motility, adhesion, and biofilm formation. Compared to those fish infected with the wild-type strain of P. plecoglossicida, orange-spotted grouper infected with the flgK-RNAi strain showed a 55% increase in the survival rate and a one-day delay in time of first death, with fewer pathogens in the spleen and fewer white spots on the spleen surface. RNAi of flgK significantly affected the transcriptome and metabolome of the spleen in infected orange-spotted grouper. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the C-type lectin receptor signaling pathway was the most significantly changed immune-related pathway and the mitogen-activated protein kinase (MAPK) signaling pathway was related to multiple immune-related pathways. Furthermore, arginine biosynthesis and glycerophospholipid metabolism were the most significantly changed metabolism-related pathways. These findings suggest that flgK is a virulence gene of P. plecoglossicida. Furthermore, flgK appears to be involved in the regulation of motility, adhesion, and biofilm formation in P. plecoglossicida, as well as in the regulation of inflammatory and immune responses of orange-spotted grouper to P. plecoglossicida infection.

Isolation and Characterization of a Novel Vibrio natriegens—Infecting Phage and Its Potential Therapeutic Application in Abalone Aquaculture

Phage-based pathogen control (i.e., phage therapy) has received increasing scientific attention to reduce and prevent the emergence, transmission, and detrimental effects of antibiotic resistance. In the current study, multidrug-resistant Vibrio natriegens strain AbY-1805 was isolated and tentatively identified as a pathogen causing the death of juvenile Pacific abalones (Haliotis discus hannai Ino). In order to apply phage therapy, instead of antibiotics, to treat and control V. natriegens infections in marine aquaculture environments, a lytic phage, vB_VnaS-L3, was isolated. It could effectively infect V. natriegens AbY-1805 with a short latent period (40 min) and high burst size (~890 PFU/cell). Treatment with vB_VnaS-L3 significantly reduced the mortality of juvenile abalones and maintained abalone feeding capacity over a 40-day V. natriegens challenge experiment. Comparative genomic and phylogenetic analyses suggested that vB_VnaS-L3 was a novel marine Siphoviridae-family phage. Furthermore, vB_VnaS-L3 had a narrow host range, possibly specific to the pathogenic V. natriegens strains. It also exhibited viability at a wide range of pH, temperature, and salinity. The short latent period, large burst size, high host specificity, and broad environmental adaptation suggest that phage vB_VnaS-L3 could potentially be developed as an alternative antimicrobial for the control and prevention of marine animal infections caused by pathogenic V. natriegens.

Probiotics Bacillus cereus and B. subtilis reshape the intestinal microbiota of Pengze crucian carp (Carassius auratus var. Pengze) fed with high plant protein diets

The intestinal dysfunction induced by high plant protein diets is frequently observed in farmed fish, and probiotics of Bacillus genus were documented to benefit the intestinal health through the modulation of intestinal microbiota without clearness in its underlying mechanism yet. Fusobacteria, Proteobacteria, and Firmicutes were observed to be the dominate phyla, but their proportion differentiated in the intestinal bacterial community of Pengze crucian carp (Carassius auratus var. Pengze) fed different diets in this study. Dietary supplementation of B. cereus and B. subtilis could reshape the intestinal bacterial community altered by high plant protein diets through a notable reduction in opportunistic pathogen Aeromonas together with an increase in Romboutsia and/or Clostridium_sensu_stricto from Firmicutes. Due to the alteration in the composition of bacterial community, Pengze crucian carp exhibited characteristic ecological networks dominated by cooperative interactions. Nevertheless, the increase in Aeromonas intensified the competition within bacterial communities and reduced the number of specialists within ecological network, contributing to the microbial dysbiosis induced by high plant protein diets. Two probiotics diets promoted the cooperation within the intestinal bacterial community and increased the number of specialists preferred to module hubs, and then further improved the homeostasis of the intestinal microbiota. Microbial dysbiosis lead to microbial dysfunction, and microbial lipopolysaccharide biosynthesis was observed to be elevated in high plant protein diets due to the increase in Aeromonas, gram-negative microbe. Probiotics B. cereus and B. subtilis restored the microbial function by elevating their amino acid and carbohydrate metabolism together with the promotion in the synthesis of primary and secondary bile acids. These results suggested that dietary supplementation of probiotics B. cereus and B. subtilis could restore the homeostasis and functions of intestinal microbiota in Pengze crucian carp fed high plant protein diets.

Intestinal microbiome-mediated resistance against vibriosis for Cynoglossus semilaevis

BACKGROUND

Infectious diseases have caused huge economic loss and food security issues in fish aquaculture. Current management and breeding strategies heavily rely on the knowledge of regulative mechanisms underlying disease resistance. Though the intestinal microbial community was linked with disease infection, there is little knowledge about the roles of intestinal microbes in fish disease resistance. Cynoglossus semilaevis is an economically important and widely cultivated flatfish species in China. However, it suffers from outbreaks of vibriosis, which results in huge mortalities and economic loss.

RESULTS

Here, we used C. semilaevis as a research model to investigate the host-microbiome interactions in regulating vibriosis resistance. The resistance to vibriosis was reflected in intestinal microbiome on both taxonomic and functional levels. Such differences also influenced the host gene expressions in the resistant family. Moreover, the intestinal microbiome might control the host immunological homeostasis and inflammation to enhance vibriosis resistance through the microbe-intestine-immunity axis. For example, Phaeobacter regulated its hdhA gene and host cyp27a1 gene up-expressed in bile acid biosynthesis pathways, but regulated its trxA gene and host akt gene down-expressed in proinflammatory cytokines biosynthesis pathways, to reduce inflammation and resist disease infection in the resistant family. Furthermore, the combination of intestinal microbes and host genes as biomarkers could accurately differentiate resistant family from susceptible family.

CONCLUSION

Our study uncovered the regulatory patterns of the microbe-intestine-immunity axis that may contribute to vibriosis resistance in C. semilaevis. These findings could facilitate the disease control and selective breeding of superior germplasm with high disease resistance in fish aquaculture. Video Abstract.

Perceptions and Liking Distortion from Information about the Nutritional Upgrades in Biofortified Seafood Products

(1) Background: As biofortified fish meat is becoming increasingly available, the use of supplements within fish feed may impact consumers’ perceptions and their willingness to pay (WTP) for the product. This study focused on evaluating the sensory liking of, and WTP for, fish produced with fortified feed while understanding the role played by the acquired information on fish fortification. (2) Methods: Hedonic ratings and WTP were measured in an experimental bid. The participants (n = 91) were asked to rate pleasantness and WTP during two different rounds: (i) appearance–information–tasting and (ii) appearance–tasting–information. A total of three fish species (carp, seabream, and trout) were presented to the consumers as being either fortified (with iodine, selenium, and omega-3 fatty acids) or conventional products. (3) Results: For pleasantness, no significant differences were found between the fortified and conventional fish. In contrast, substantial differences emerged when information regarding the products was provided. Providing the relevant information before tasting affected how much the consumers liked the conventional fish, resulting in a preference for it over the fortified fish. Additionally, consumers are willing to pay more for fortified fish, especially when information with respect to fortification is available. Nevertheless, when information about fortification was provided before tasting, the consumer’s expectations were not fulfilled. (4) Conclusions: The outcomes of this study clearly indicate that the presence of relevant information impacts how much people like fortified versus conventional fish, as well as their WTP.

Proteomic Applications in Aquatic Environment Studies

Genome determines the unique individualities of organisms; however, proteins play significant roles in the generation of the colorful life forms below water. Aquatic systems are usually complex and multifaceted and can take on unique modifications and adaptations to environmental changes by altering proteins at the cellular level. Proteomics is an essential strategy for exploring aquatic ecosystems due to the diverse involvement of proteins, proteoforms, and their complexity in basic and advanced cellular functions. Proteomics can expedite the analysis of molecular mechanisms underlying biological processes in an aquatic environment. Previous proteomic studies on aquatic environments have mainly focused on pollution assessments, ecotoxicology, their role in the food industry, and extraction and identification of natural products. Aquatic protein biomarkers have been comprehensively reported and are currently extensively applied in the pharmaceutical and medical industries. Cellular- and molecular-level responses of organisms can be used as indicators of environmental changes and stresses. Conversely, environmental changes are expedient in predicting aquatic health and productivity, which are crucial for ecosystem management and conservation. Recent advances in proteomics have contributed to the development of sustainable aquaculture, seafood safety, and high aquatic food production. Proteomic approaches have expanded to other aspects of the aquatic environment, such as protein fingerprinting for species identification. In this review, we encapsulated current proteomic applications and evaluated the potential strengths, weaknesses, opportunities, and threats of proteomics for future aquatic environmental studies. The review identifies both pros and cons of aquatic proteomics and projects potential challenges and recommendations. We postulate that proteomics is an emerging, powerful, and integrated omics approach for aquatic environmental studies.

Review of Medicinal Plants and Active Pharmaceutical Ingredients against Aquatic Pathogenic Viruses

Aquaculture offers a promising source of economic and healthy protein for human consumption, which can improve wellbeing. Viral diseases are the most serious type of diseases affecting aquatic animals and a major obstacle to the development of the aquaculture industry. In the background of antibiotic-free farming, the development and application of antibiotic alternatives has become one of the most important issues in aquaculture. In recent years, many medicinal plants and their active pharmaceutical ingredients have been found to be effective in the treatment and prevention of viral diseases in aquatic animals. Compared with chemical drugs and antibiotics, medicinal plants have fewer side-effects, produce little drug resistance, and exhibit low toxicity to the water environment. Most medicinal plants can effectively improve the growth performance of aquatic animals; thus, they are becoming increasingly valued and widely used in aquaculture. The present review summarizes the promising antiviral activities of medicinal plants and their active pharmaceutical ingredients against aquatic viruses. Furthermore, it also explains their possible mechanisms of action and possible implications in the prevention or treatment of viral diseases in aquaculture. This article could lay the foundation for the future development of harmless drugs for the prevention and control of viral disease outbreaks in aquaculture.

Intensive production of the harpacticoid copepod Tigriopus californicus in a zero-effluent 'green water' bioreactor

Aquaculture is looking for substitutes for fishmeal and fish oil to maintain its continued growth. Zooplankton is the most nutritious option, but its controlled mass production has not yet been achieved. In this context, we have developed a monoalgal 'green water' closed-loop bioreactor with the microalgae Tetraselmis chui that continuously produced the harpacticoid copepod Tigriopus californicus. During 145 days of operation, the 2.2 m³ bioreactor produced 3.9 kg (wet weight) of Tigriopus with (dry weight) 0.79 ± 0.29% eicosapentaenoic acid (EPA), 0.82 ± 0.26% docosahexaenoic acid (DHA), 1.89 ± 0,60% 3S,3'S-astaxanthin and an essential amino acid index (EAAI) of 97% for juvenile Atlantic salmon. The reactor kept the pH stable over the operation time (pH 8.81 ± 0.40 in the algae phase and pH 8.22 ± 2.96 in the zooplankton phase), while constantly removed nitrate (322.6 mg L^-1) and phosphate (20.4 mg L^-1) from the water. As a result of the stable pH and nutrient removal, the bioreactor achieved zero effluent discharges. The upscaling of monoalgal, closed-loop 'green water' bioreactors could help standardize zooplankton mass production to supply the aquafeeds industry.

Concentration dataset of 8 selected trace elements in cultured rainbow trout (Oncorhynchus mykiss) and dietary exposure risks in the Missouri adult population

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Concentrations of eight trace elements in O. mykiss from aquaculture.

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Only Cr, in some samples, exceeded the permissible limit.

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EWI values of analyzed trace elements were below the PTWIs.

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Arsenic was the highest contributor to non-carcinogenic risk in adult consumers.

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Cancer risk of As, Cd, Cr, and Pb in the adult population is probable.

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High intake per week of O. mykiss posed health risks to the adult risk group.

Aquaculture contributes to the global animal protein supply and the prevention of malnutrition and diet-related diseases (FAO (Food and Agriculture Organization of the United Nations); Fiorella et al., 2021). In particular, fish is a significant source of animal protein, fatty acids (e.g., docosahexaenoic acid, eicosapentaenoic acid), vitamins, and essential trace elements in the human diet. Nonetheless, fish bioaccumulates metals from their diet and habitat. This data article includes information on the concentrations of 4 essential and 4 non-essential trace elements in cultured rainbow trout (Oncorhynchus mykiss) and the human health risks through fish consumption in the adult population. Concentrations of four essential (Cr, Cu, Ni, and Zn) and four non-essential (As, Cd, Pb, and Hg) elements were quantified in ninety-one O. mykiss samples from an in-door production system. Total mercury (THg) levels in samples were determined by AAS, and other analyzed trace elements were measured by ICP-OES after microwave-assisted acid digestion. The highest concentrations of metals/metalloid (mg/kg wet weight) in fish muscle were Cr (0.44), Cu (4.21), Ni (1.01), As (0.47), Cd (0.045), Pb (0.65), THg (0.029), and Zn (6.21). The average concentrations of Cr and Pb exceeded their respective maximum limit. In most cases, median metal concentrations significantly (p < 0.05) differed across the fish size groups (small: 264–295 mm; medium: 300–395 mm; and large: 400–552 mm). The median concentrations of Cd, Zn, and THg in the large size group differed significantly (p < 0.05) between genders. The estimated weekly intake values of quantified elements from muscle were below the provisional tolerable weekly intakes. Non-carcinogenic risk assessment in adult consumers, being below one (THQ ≤ 1; and TTHQ ≤ 1), indicated an insignificant health hazard. The estimated incremental and cumulative cancer risks in the adult class through Cr, As, Ni, and Pb exposure were greater than the benchmark (10⁻⁵). Accordingly, high dietary intake of metals/metalloid from cultured O. mykiss posed a risk of carcinogenesis in the adult risk class.

Cultivated and Wild Juvenile Thick-Lipped Grey Mullet, Chelon labrosus: A Comparison from a Nutritional Point of View

The thick-lipped grey mullet (Chelon labrosus) is a nominee fish species for aquaculture diversification in Spain because it is an omnivore and euryhaline species, but limited knowledge about the nutritional attributes of this species is available. This study aimed to characterize the chemical composition of wild and cultured fish. The muscle proximate composition, and fatty acid and amino acid profiles were assessed. The cultivated specimens showed a higher lipid content and lower protein and ash contents compared with the wild specimens. The predominant tissue fatty acids in both the wild and cultivated fish were palmitic acid (16:0), oleic acid (18:1n-9) and docosahexaenoic acid (DHA, 22:6n-3). A higher content of arachidonic acid (ARA, 20:4n-6), eicosapentaenoic acid (20:5n-3) and DHA were detected in the muscle of wild mullets, while the fish supplied with commercial pellets showed higher quantities of monounsaturated fatty acids, and lower quantities of saturated fatty acids and polyunsaturated fatty acids (PUFAs). Regarding PUFAs, n-3 fatty acids were predominant in wild mullets, while n-6 and n-9 were more abundant in farmed fish. In terms of amino acid composition, except for histidine in wild specimens, the amino acid amounts were higher than the FAO/WHO standard. In conclusion, C. labrosus may contribute to improving the dietary intake of highly polyunsaturated n-3 fatty acids, with a benefit to human health, owing to that fact that a 100-g fillet portion of cultivated and wild C. labrosus can provide 770 mg and 1160 mg of EPA and DHA, respectively, which exceeds the 250 mg dietary daily intake recommended by the FAO/WHO.