Commercial Fish Species Research Articles

Effect of Habitat and Feeding Pattern on the Chemical Composition and Accumulation of Heavy Elements in Some Marine Fish Species in the Syrian Coast

The study was conducted during the year 2021 to measure chemical composition and heavy elements (cadmium, lead, copper, and nickel) within the muscle tissue of four commercial fish species (Sardinella aurita, Siganus rivulatus, Parupeneus forsskali and Chelon auratus) caught in the marine waters of Latakia Governorate-Syria.

Chromosome-level genome assembly of the small yellow croaker, Larimichthys polyactis (Perciformes: Sciaenidae)

Small yellow croaker (Larimichthys polyactis) represents an important commercial fish species in China. A high-quality genome is essential for evaluating the fine-scale genetic structure, which has significant implications for the conservation of wild stocks, fishery management, and the utilization of germplasm in L. polyactis. This study presents a chromosome-level genome of L. polyactis generated by employing the PacBio high-fidelity (HiFi) and high-throughput chromosome conformation capture (Hi-C) technologies. The complete genome spans 677.35 Mb with a scaffold N50 size of 28.51 Mb. A substantial portion of the genome, totaling 663.13 Mb (97.90%), was anchored to 24 chromosomes. Based on Benchmarking Universal Single-Copy Ortholog (BUSCO) analysis, L. polyactis exhibits high genomic completeness (98.00%). A total of 28,640 annotated genes were identified, with 25,801 being functionally annotated. The comparisons of 24 chromosomes between L. polyactis and L. crocea proved high conservation of synteny between this pair of relatives. These findings provide valuable resources for the conservation, functional genomics, molecular breeding and evolutionary studies of L. polyactis.

Single and joint toxicity of ethoprophos and bispyribac-sodium to Oreochromis niloticus: biochemical and genotoxic responses

Pesticides can bioaccumulate in fish tissues, and there are serious concerns around the world about their effects on consumer health. The objective of this study was to highlight the effects of two commercial pesticides, ethoprophos and bispyribac-sodium, commonly used on high-consumption crops in Egypt, either individually or in mixture, on some biomarkers of Nile tilapia, Oreochromis niloticus, an important commercial fish species. Low concentrations of ethoprophos (96 µg/L) and bispyribac-sodium (1.28 µg/L) were selected to evaluate the effect of these substances on neurotoxic marker (acetylcholine esterase, AChE), liver function parameters (alkaline phosphatase, ALP; alanine aminotransferase, ALT; and aspartate aminotransferase, AST), and renal function parameters (creatinine and urea), as well as genotoxic marker (micronuclei, MN; and other nuclear abnormalities) during variable periods (7, 14, 21, and 28 days). The results demonstrate that ethoprophos and bispyribac-sodium pose a risk to native freshwater fish by causing detrimental effects. Both compounds, separately and in combination, induced neurotoxicity, hepatorenal biomarkers inductions, and increases in MN frequency and other erythrocytic nuclear abnormalities in a time-dependent manner. Moreover, the mixture displayed both synergistic and antagonistic interactions for examined parameters. This study highlights the importance of using validated biomarkers to monitor fish health, which may be utilized as early alarms of environmental risks.Graphical

The research of the main commercial fish species in the Sea of Azov during the accounting trawl survey in October-November 2024

The aim: quantitative account and collect material on the qualitative characteristics of commercial fish species and monitor the habitat of aquatic biological resources of the Sea of Azov in the autumn period of 2024.Methods: during the execution of trawl survey, the collection and primary processing of materials were carried out in accordance with generally accepted methods.Innovations: materials on the biological state of fish, qualitative and quantitative composition of aggregations have been collected, identified patterns in the spatial and seasonal distribution of the main commercial fish species of the Sea of Azov.Results: the average water temperature in the Sea of Azov was 10,8 °C, in the Taganrog Bay – 6,5 °C. The average weighting salt’s concentration of the Sea of Azov was 15,22‰, and that of the Taganrog Bay was 11,67‰. The first place in catches was occupied by the Black and Caspian Sea sprat (26,3%), the second by the European anchovy (25,4%), and the third by the Danube sturgeon (20,3%). Black and Caspian Sea sprat and European anchovy were concentrated mainly in the central part of the Sea of Azov and the Taganrog Bay, with the largest catches amounting to 100 and 55 kg/hour of trawling. Concentration of Danube sturgeon was observed in the western part of the sea off the coast of Crimea and in the northern part of the sea in the area of Byriuchyi Island. The largest catch was 102 kg/hour of trawling. Concentration of Black Sea turbot were mainly recorded in the northwestern and central parts of the Sea of Azov, with the largest catch being 16 kg/ hour of trawling. The Pontic shad was mainly found in the northwestern, southwestern, and central parts of the Sea of Azov and in the pre-strait, with a maximum catch of 6 kg/hour of trawling.The practical significance: the results of the work will be used to refine and develop forecasts of the recommended volume of extraction (catch) of aquatic biological resources and recommendations for effective fishing.

Biological indicators of the main commercial fish species (Caspian roach, kutum, bream, Caspian vimba, shemaya) of the Samur coast of the Caspian Sea

Biological indicators of the main commercial fish species (Caspian roach, kutum, bream, Caspian vimba, shemaya) of the Samur coast of the Caspian Sea

Evaluation of some heavy metals in water and health implications for fish consumers of the Great Cairo Sector of the Nile River

Rivers serve crucial functions in the worldwide hydrological cycle. The industrial revolution, climate change, and urban development generated diverse water contaminants. This work aimed to assess the regional and seasonal distribution of some heavy metals (HMs) in the hot spot sites along the Great Cairo Sector, Nile River during 2021–2022. In addition, two commercial fish species (O. niloticus and C. gariepinus) were selected for assessing heavy metal content and human health risk. The results of heavy metals in water varied within; (1–7), (45–85.5), (19–84), (148–376), and (65–170) µg/l for Cd, Cu, Pb, Mn, and Zn, respectively over the study period. The heavy metal pollution index (HPI) results categorized the water status as unsuitable for drinking and aquatic life, but ideal for irrigation purposes. Based on Metal Index (MI) values, all examined sites were significantly at risk of metal contamination (> 1) over all uses. In the two investigated species, The results of Cd, Cu, Pb, Mn, and Zn varied in the edible part of fish species within (0.2–0.28), (2.01–5.41), (0.21–1.11), (12.1-15.25), (20.91–32.52) mg/g ww, respectively, for O. niloticus and within (0.2–0.35), (3.12–6.5), (1.52–3.62), (15.01–17.72), (15.12–26.93) mg/g ww, respectively, for C. gariepinus over the study period. The total annual daily intake of HMs was estimated to be 0.03625 and 0.03725 mg/kg.bw.day from the human consumption of O. niloticus and C. gariepinus, respectively. The Target Hazard Quotient (THQ) ranked in the order of Cd > Pb > Mn > Zn > Cu for O. niloticus and in the order of Pb > Cd > Mn > Cu > Zn for C. gariepinus with values lower than 1 that reported non-carcinogenic risk for consumers from the ingestion of investigated HMs seperately. Moreover, the Health Hazard Index (HI) slightly exceeded the threshold value of 1 of C. gariepinus, classified as moderate risk levels for consumers. Conversely, HI values were below 1 for O. niloticus, suggesting no risk from this species’ consumption. This study recommended an assertive water-quality monitoring strategy to mitigate health-related outbreaks and disruptions in aquatic ecosystems. The supplied data will undeniably assert environmental policymakers to implement sustainable pollution management and remediation measures.

The molecular mechanism of ovary development in Thamnaconus septentrionalis induced by rising temperature via transcriptomics and metabolomics analysis

The greenfin horse-faced filefish, Thamnaconus septentrionalis, which is widely distributed in the Indo-West Pacific Ocean, is an important commercial fish species with characteristic blue-green fins, rough skin, and a spine-like first dorsal fin. Recently, T. septentrionalis has captured the attention of conservation and development due to its sharply declining population, and its great economic value as an important marine aquaculture fish species. To protect the resources of T. septentrionalis and develop its fishery industry, artificial breeding is essential and has been carried out gradually in local farms in China. A previous study has shown that temperature can effectively influence the gonadal development in T. septentrionalis in its overwintering state. However, the molecular mechanisms underlying the effects of temperature on the gonadal development in T. septentrionalis are still unrevealed and worth further study. In the present study, we systematically investigated the effects of temperature on ovary development in T. septentrionalis through transcriptomics and metabolomics analysis. The results showed that temperature rises significantly regulated the metabolic status of T. septentrionalis and promoted ovary development and maturation process through the regulation of the pathways of ECM-receptor interaction, regulation of actin cytoskeleton, oocyte meiosis, steroid hormone biosynthesis, lipid metabolism, ABC transporters, protein digestion and absorption, biosynthesis of amino acids pathways, etc. The histological, scanning electron microscope, and transmission electron microscope analyses showed that the oocytes in the ovaries of T. septentrionalis experiencing the temperature rises developed from phase II to III with increased gonadal somatic index and 17β-estradiol level. The present study for the first time elucidated the potential molecular regulatory mechanism of ovary development in T. septentrionalis induced by temperature and will provide valuable information for the artificial breeding of T. septentrionalis and conservation of T. septentrionalis fishery resources in the future.

Comparing Ecosystem Structure and Function of the Geheyan Reservoir Based on the Ecopath Model After a Fishing Ban

The Geheyan Reservoir, located on the Qingjiang River, a tributary of the Yangtze River, is important for regional water supplies and ecological conservation. Understanding changes in ecosystem structure and function has become critical for assessing efficacy after the implementation of a fishing ban. This study employs the Ecopath model to examine the ecosystem characteristics of the Geheyan Reservoir before (2017) and after (2022) the fishing ban. The results show significant differences in trophic levels, energy transfer efficiency, and ecosystem maturity between the two periods. The trophic levels increased from 3.36 pre-fishing ban to 3.89 post-ban, indicating an enhanced complexity in the food web structure. The highest eco-trophic efficiency for major commercial fish species increased after the ban, indicating improved energy utilization efficiency. However, energy transfer bottlenecks were still observed between trophic levels II and IV, suggesting ongoing challenges in nutrient cycling. The total primary production-to-total respiration ratio (6.93) and the connectivity index (0.25) indicate that the ecosystem’s maturity and stability have improved after the fishing ban. These findings underscore the ban’s effectiveness and provide a scientific foundation for sustainable management of Geheyan Reservoir and similar ecosystems in the Yangtze River Basin.

Natural and Regenerated Cellulosic Microfibers Dominate Anthropogenic Particles Ingested by Commercial Fish Species from the Adriatic Sea.

This study investigated the occurrence of fibrous microplastics and natural and artificial cellulose microfibers in the gastrointestinal tracts of Mullus barbatus and Merluccius merluccius specimens from the Adriatic Sea (Central Mediterranean), an important hotspot for marine litter accumulation. Red mullet and European hake were chosen due to their roles as bioindicators of marine pollution in the Mediterranean, and their economic relevance as fishery resources. Microfibers were found in 72% of M. barbatus and 68% of M. merluccius, at levels ranging from 1 to 67 particles/individual. Most of the microfibers extracted were textile fibers that were blue (33.6%), clear (26.1%), and black (20.3%) in color, while the length distribution showed the prevalence of microfibers in the size range of 350-950 µm. This visual identification, corroborated by the micro-FTIR analysis of a sub-sample of microfibers, revealed that natural and artificial cellulose microfibers were more common (80%) than fibrous microplastics. The results confirmed that both of these fish species are susceptible to microfiber ingestion and indicated the high availability of natural and artificial cellulosic fibers in the Adriatic Basin. Despite the increased evidence of microfiber pollution in the marine ecosystem, only a limited number of studies examine natural/artificial microfiber contamination and ingestion by marine biota. Therefore, greater attention should be given to this new type of contaminant, considering its implications in terms of environmental health, food security, and food safety.

Chinese yam polysaccharide induces the differentiation and natural antibody secretion of IgM+ B cells to prevent Aeromonas hydrophila infection in grass carp.

Chinese yam polysaccharide induces the differentiation and natural antibody secretion of IgM+ B cells to prevent Aeromonas hydrophila infection in grass carp.

Life history of sprat (Sprattus sprattus) in the Black Sea under warming and fishing: current state and patterns of variability.

Sprat Sprattus sprattus (Linnaeus, 1758) is one of the most significant commercial fish species in the Black Sea. This study examines the sex ratio, size-age structure, growth, and mortality of sprat in the waters of Crimea from 2021 to 2023. The paper discusses the geographic variability and the influence of temperature, food availability, and fishing pressure on the life history of this species. In total, 2113 individuals from commercial catches were examined. The sex ratio was slightly skewed towards females (1:0.83). The maximum total length for both males and females was 10.0 cm, with a maximum weight of 8.51 g for females and 6.73 g for males. The lifespan for both sexes was 4 years. The Bertalanffy growth equation parameters were calculated, with L∞ = 13.79 cm, W∞ = 16.3 g, K = 0.237 year-1 and t0 = -1.53 year. The exponent value in the length-weight relationship was 3.14 (positive allometric relationship). The total, natural and fishing mortality coefficients for both sexes were 2.13, 0.65 and 1.48 year-1, respectively, and the exploitation ratio was 0.70, indicating excessive fishing pressure. It was determined that sprat from lower latitudes had smaller sizes, slower growth rates and shorter lifespans compared to sprat from higher latitudes. A strong negative correlation was found between the size and lifespan of sprat and sea surface temperature. Excessive fishing pressure against the backdrop of climate warming was identified as the cause of the reduction in lifespan and size of sprat in the Black Sea, therefore it is recommended to reduce the volume of sprat fishing and increase its minimum landing size to preserve the population of sprat in the Black Sea.

Assessment of the state of fishery and results of research on stocks of commercial fish species in retrospective aspect and at the present stage of fishery development of Tsimlyansk reservoir

The Tsimlyansk Reservoir is one of the most important inland freshwater bodies of water in the Russian Federation, which continues to provide an annual catch of aquatic bioresources of up to 8–10 thousand tons, which is 5–7 % of the fish caught in freshwater bodies of water in the country. The Tsimlyansk Reservoir, for more than 70 years of history from the moment of its formation to the present day, remains one of the most fish-productive among inland water bodies with commercial fish productivity of 45–50 kg / ha in previous years, maintaining a fairly high commercial and economic importance for a long time. Multi-species fishing is carried out on the reservoir, the total catch consists of bioresources of seventeen fish species. In this regard, the targets and corresponding biological reference points for stock assessment and exploitation vary among fish species.

Arsenic Speciation, an Evaluation of Health Risk Due to the Consumption of Two Fishes from Coastal Marine Areas of the Southwestern Atlantic Ocean (SWAO).

Arsenic (As) is naturally occurring and is found in different forms, some of which are considered toxic to human health and frequently present in fishery resources. The aim of this work was to determine the contribution of toxic As species to the total As in muscle of two commercial fish species (Micropogonias furnieri and Urophycis brasiliensis) and to assess the toxicological risk associated with their consumption, considering different exposed groups. The total As concentrations found exceeded local guideline recommendations (> 1mgkg-1 wet weight), but the concentrations of the toxic As species were below this threshold. The inorganic As levels do not exceed the international guideline recommendations (0.03-0.15μgkg-1 bw per day of iAs). Both interspecific and intraspecific differences in As concentrations were found. Non-carcinogenic and carcinogenic risk values indicated that the exposed groups would not experience health risks through consumption of either fish species. However, due to the lack of an established safe consumption limit for iAs or As species worldwide, there are currently no legal tools to ensure that these fish species are safe for human consumption.

Integrated Biotechnological Strategies for the Sustainability and Quality of Mediterranean Sea Bass (Dicentrarchus labrax) and Sea Bream (Sparus aurata).

This review examines the current state of the supply chain management for Dicentrarchus labrax (sea bass) and Sparus aurata (sea bream), two key commercial fish species in the Mediterranean. It provides a comprehensive analysis of sustainable innovations in aquaculture, processing, and packaging, with particular attention to circular economy-based biopreservation techniques. A major focus is on the Integrated Multi-Trophic Aquaculture (IMTA) system, an advanced farming approach that enhances sustainability, promotes circular resource utilization, and improves fish welfare. By fostering ecological balance through the co-cultivation of multiple species, IMTA contributes to the overall quality of fish products for human consumption. Beyond aquaculture, the review addresses the critical challenge of food loss, which stems from the high perishability of fish during storage and processing. In this regard, it highlights recent advancements in biopreservation strategies, including the application of antagonistic microorganisms, their metabolites, and plant-derived extracts. Particular attention is given to the development of edible antimicrobial films, with a focus on the valorization of citrus processing by-products for their production. By centering on innovations specific to the Mediterranean context, this review underscores that a holistic, integrative approach to supply chain management is essential for transitioning the aquaculture sector toward greater efficiency and sustainability.

Size-Selective Harvesting Effects on Reproductive Investment in Marine Medaka (Oryzias melastigma)

Long-term selective fishing pressure often leads to miniaturization, smaller size, and early sexual maturity in many commercial fish species. To adapt, these species increase energy allocations toward maturation and reproduction, which can reduce population productivity and recruitment. However, how different fishing pressures affect reproductive investment and energy allocation between growth and reproduction remains unclear. In this study, we designed three size-selective harvesting strategies—large, random, and small harvests—to examine their effects on the growth and reproductive investment of marine medaka (Oryzias melastigma). We analyzed changes in length, weight, and gonad weight across different harvest times. Results showed that the “large harvest” group allocated more energy to reproduction, leading to miniaturization and earlier maturation, while the “small harvest” group focused more on growth, resulting in larger fish at the same age. This study provides experimental evidence on how size-selective harvesting alters reproductive investment in fish populations, offering valuable insights for the sustainable exploitation of fishery resources.

Extraction and Characterization of Biogenic Nano-Calcium Derived from Daysciaena albida and Otolithes ruber: Potential Applications.

In India, widespread dietary deficiency in calcium and vitamin D is a significant public health concern. Over the past five decades, evidence has shown a decline in dietary calcium intake in rural, tribal and urban populations. This persistent deficiency poses a serious risk to bone health and contributes to the development of rickets, osteoporosis and osteopenia, as well as potential disturbances in metabolic rates and physiological functions. A key factor in this decline appears to be the reduced consumption of calcium-rich dairy products. As a result, research is exploring alternative, highly bioavailable sources of calcium, such as those derived from fish bone waste. The potential of nano-calcium supplements to improve absorption and bone density compared to traditional supplements is an area of active investigation. Nano-calcium powder was synthesised from the bones of two commercial fish species, Daysciaena albida and Otolithes ruber, ethically sourced from the Kerala coast following relevant regulations. Alkali extraction method was used and the resulting nano-calcium powder was characterized by various physiological and chemical analyses. The yield percentage of two samples was different. Notably, both samples had different colour properties, proximate composition and results of scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). The nano-calcium from D. albida also contains slightly more calcium and phosphorus than that from O. ruber. The nanoparticles of the calcium from D. albida (d=153.8 nm) were also smaller than the nanoparticles of the calcium from O. ruber (d=337.1 nm). Interestingly, further analyses using techniques such as Fourier transform infrared spectroscopy (FTIR), zeta potential, thermogravimetric analysis (TGA) and X-ray diffraction (XRD) showed significant similarity between the nano-calcium samples from D. albida and O. ruber, despite the initial differences in yield, composition and particle size. This result suggests that the choice of fish species significantly affects the yield, composition and properties of the synthesised nano-calcium powder with D. albida appearing to be a more favorable source, but both products can exhibit similar functionality and warrant further investigation. This is the first report on the extraction and characterization of biogenic nano-calcium from two commercial fish, Daysciaena albida and Otolithes ruber from the Malabar Coast, India. The extracted nano-calcium powders from these two fish are a good source of calcium and help overcome calcium-related disorders.

Deploying artificial nurseries in port areas: A complementary strategy to fisheries management for supporting coastal fish populations.

Conservation measures are essential for supporting biodiversity in areas impacted by human activities. Over the last decade, efforts to rehabilitate fish nursery habitats in ports through eco-engineering have gained attention. While these interventions show promise at a local level such as increased juvenile fish densities on artificial eco-engineered habitats compared to unmodified port environments there has been no comprehensive assessment of their contribution to coastal fish population recovery or their effectiveness relative to traditional conservation measures like fishing regulations. In this study, we employed the ISIS-Fish model, which integrates fish population dynamics with fisheries management, to examine the commercial coastal fish species, white seabream (Diplodus sargus), in the highly artificialized Bay of Toulon. By simulating different rehabilitation scenarios and fisheries management strategies, we provided the first quantitative evaluation of eco-engineered structure deployment in ports, covering 10% and 100% of the available port's linear extent. We compared these rehabilitation outcomes against the effects of enforcing strict minimum catch sizes. Our findings indicate that while port nursery habitat rehabilitation can contribute to fish population renewal and increase catches, the benefits remain limited when project scales are small, especially when compared to the impacts of strict fishing regulations. However, a synergistic effect was observed when combining nursery rehabilitation with fishing control measures, leading to significant improvements in fish populations and catch yields. This study offers the first quantitative analysis of nursery habitat rehabilitation in ports, highlighting its potential as a supplementary strategy to fisheries management, though less effective on its own than robust regulatory measures.

Biological indicators of some small commercial fish species (vimba, kutum, walleye) in the northern part of the Agrakhan Bay of the Caspian Sea in 2018-2022

Biological indicators of some small commercial fish species (vimba, kutum, walleye) in the northern part of the Agrakhan Bay of the Caspian Sea in 2018-2022

Effect of Dietary Supplementation of Chlorella vulgaris on Liver Biomarkers and Lipid Profile on Clarias gariepinus

Clarias gariepinus is an important commercial fish species in Nigeria and is widely cultivated by many farmers. This study investigated the effects of dietary supplementation with Chlorella vulgaris on liver biomarkers and lipid profiles in Clarias gariepinus over 12 weeks. Five groups of fish were used in the study; one group served as the control, while the other four groups were fed different concentrations of the algae at 5%, 10%, 15%, and 20%. At the end of the feeding trial, the fish were anesthetized using clove oil, and blood samples were collected for analysis. The results indicated that the supplementation of C. vulgaris in the diets of C. gariepinus led to higher protein percentages (ranging from 43.0% to 47.3%) and lower levels of AST (230.0) and ALT (54.0) in the algae-fed groups compared to the control group, which had a protein percentage of 39.67, AST levels of 497.3, and ALT levels of 180.7. Additionally, the lipid profiles showed that the treated groups had better outcomes than the control group. The findings revealed significant variations in the fish's serum biochemical parameters and lipid profiles across the different treatments. Therefore, this study highlights the positive impact of microalgae as a physiological booster in C. gariepinus.

The overlooked impacts of freshwater scarcity on oceans as evidenced by the Mediterranean Sea

Water stress is an urgent issue in many regions worldwide, particularly in southern European countries. This study reveals the consequences of decreased freshwater flow on marine ecosystems in the Mediterranean Sea due to climate change and escalating water demands. A 41% reduction in river flow may result in a 10% decline in marine primary productivity and a 6% decrease in biomass of commercial fish and invertebrate species. Regional reductions could be as high as 12% and 35%, disrupting coastal and marine ecosystems and their related socio-economic sectors. The findings emphasize the importance of considering nutrient load changes in water management strategies and incorporating marine ecosystem requirements into environmental flow requirements for freshwater bodies. Integrated, source-to-sink management approaches are crucial for sustainable water resource utilization.