Exploring reported population differences in Norway lobster (Nephrops norvegicus) in the Pomo Pits region of the Adriatic Sea using genome-wide markers.

The Norway lobster (Nephrops norvegicus) is one of the most important decapod crustacean seafood species in the Adriatic Sea. Previous research has identified significant differences in growth rates and maturation timing of Nephrops in the Pomo/Jabuka Pits area compared to other subpopulations in Adriatic fishing grounds. Here, we use 1,623 genome-wide single nucleotide polymorphisms (SNPs) to investigate whether the Pomo Pits subpopulation is genetically different from other sites in the Adriatic and neighbouring seas. We found no genetic differentiation among all sampled Adriatic sites, suggesting high gene flow between Pomo Pits Nephrops and those of surrounding areas. We also found genetic homogeneity between the Adriatic sites and single-site samples from the Aegean and Tyrrhenian Seas. However, we detected distinct genetic differentiation between all Mediterranean sites and an Atlantic site in western Scotland, which provides evidence for a phylogenetic break between the Atlantic and the Mediterranean. Our results indicate that Pomo Pits Nephrops are not genetically different from others sampled in the Adriatic and that key biological parameters in Pomo Pits Nephrops could be driven by spatial variation in fishing pressure and/or environmental factors rather than geographic isolation.

Evaluation of Consumer Perception of New Aquaculture Products through Applying Focus Group and Check-All-That-Apply Methodologies.

A growing interest in healthy diets has increased demand for fish and seafood, with aquaculture playing a crucial role in meeting this need. Developing new aquaculture products can enhance their commercial value and address consumer demand, but it is unclear which products will be well-received. This study aimed to generate ideas for new products derived from sea bream and prawns, and to gather consumer opinions on these ideas, segmented by gender and age. Two methodologies were used: focus groups and Check-All-That-Apply (CATA). In the focus groups, with two sessions per species and 10 participants each, ideas for aquaculture products were generated and categorized as fresh, dehydrated, fermented, marinated, and canned. The CATA technique, applied to 387 individuals, assessed the acceptability of fresh species, yielding average scores of 6.6 for sea bream and 6.8 for prawns. Sea bream was associated with products like fillets and long-shelf-life loins, while prawns were linked to snacks and toppings. In conclusion, the use of tools like focus groups has shown promising results for developing new aquaculture products. CATA analysis indicated that sea bream should be minimally processed with a long shelf life, and prawns should be processed into dehydrated products. Women preferred traditional products, while men favoured innovative options.

Can consumers avoid mislabelling? Genetic species identification provides recommendations for shrimp/prawn products.

BACKGROUND: Crustaceans of the superfamily Penaeoidea (e.g., shrimps and prawns) are among the most commercially available aquatic products worldwide. However, there are few studies regarding not only the presence but also the characteristics of mislabelling in these food products. Such information would be helpful for consumers in order to avoid the typical problems associated with mislabelling (e.g., health and economic issues). For this reason, this work considers Penaeoidea mislabelling by comparing different products (frozen, fresh, boiled), and sources (hypermarkets, supermarkets and fishmongers) from Spain (Europe). RESULTS: A total of 94 samples from 55 different products were collected, representing 19 different species from 13 genera. Mitochondrial DNA (COI gene) was amplified, revealing mislabelling in almost 30% of supermarket products and almost exclusively found in frozen samples (95% of the total) regardless of its price. In addition, products from the Pacific Ocean seem to be particularly susceptible to mislabelling. CONCLUSIONS: All in all, recommendations for the consumer in order to avoid mislabelling of prawns include purchasing them fresh from fishmongers; aquaculture products must not be avoided. This study represents, to our knowledge, the first attempt to provide recommendations to consumers based on DNA analyses in order to avoid mislabelling in food products. Further research is therefore required to provide such recommendations in different food products, particularly those that are processed, packaged and/or frozen. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

[Development of a PCR Method to Detect a Mysid Species Causing False Positives in Tests for Crustacean Allergens].

Mysids are small crustaceans that are closely related to shrimp/prawns and crabs but not subject to food allergen labeling requirements for raw materials. In the past, a processed food that contained Japanese smelt (wakasagi) was suspected of producing a false-positive result in shrimp/prawn and crab allergen test because of the presence of consumed mysids. However, there was no reported methods to confirm mysid presence. Therefore, we developed a PCR method to detect mysids. The developed PCR method had high specificity for a mysid species, with no amplification observed from samples of shrimp, crab, krill, mantis shrimp, or the meat of Japanese smelt. In addition, DNA extracted from the internal organs of Japanese smelt was amplified by this PCR method, and sequencing revealed mysid DNA. This confirmed that mysids remained in the internal organs of Japanese smelt following consumption. This PCR method for mysid detection even amplified Japanese smelt-containing processed food samples that were suspected to have produced a false-positive result in shrimp/prawn and crab ELISA. Thus, this PCR method would enable to detect such false positives are caused by mysid contamination.

Mitigation of mechanical damage and protein deterioration in giant river prawn (Macrobrachium rosenbergii) by multi-frequency ultrasound-assisted immersion freezing.

In order to investigate the effects of multi-frequency ultrasound-assisted immersion freezing (MUIF) on the meat quality of Macrobrachium rosenbergii, tail meat was subjected to different MUIF treatments respectively, namely 20 + 40 kHz (MUIF-20 + 40), 20 + 60 kHz (MUIF-20 + 60), 40 + 60 kHz (MUIF-40 + 60) and 20 + 40 + 60 kHz (MUIF-20 + 40 + 60), and the immersion freezing (IF) as control. Results showed that average diameter of ice crystals was 28 µm in IF, and that was only 8 µm in MUIF-20 + 40 + 60. When compared to IF, MUIF alleviated oxidative deterioration of lipids and proteins, but only at higher ultrasound frequency (MUIF-40 + 60; MUIF-20 + 40 + 60). Carbonyl content of MUIF-20 + 40 + 60 was only 40% of that in IF. Similarly, protein denaturation was inhibited in MUIF (except for MUIF-20 + 40). Transmission electron microscopy showed greater distortion of the ultrastructural components in IF, MUIF-40 + 60, and MUIF-20 + 40 + 60, suggested by bended Z-line. In conclusion, MUIF can be an effective strategy to mitigate mechanical damage and protein deterioration in the meat of Macrobrachium rosenbergii.

Assessing Trace Elements Bioaccumulation in Coastal River Fish and Shellfish: Implications for Human Health and Risk Evaluation.

The presence of heavy metal contaminants in fish and shellfish in aquatic environments poses a risk to human health due to trophic transfer. This study determined the levels of various trace elements (Fe, As, Cr, Zn, Cu, Ni, Pb, and Cd) in the muscles, gills, and liver of hilsa (Tenualosa ilisha) and prawn (Macrobrachium rosenbergii) samples obtained from the Tetulia River, Bangladesh. The results showed that the level of trace elements in different body parts differed significantly (P < 0.05) between species, displayed below recommended threshold levels. The cumulative low to higher hierarchic concentration of the trace elements was as follows: Fe > Zn > Cu > Cr > Ni > Pb > As > Cd. Hilsa had significantly (P < 0.05) higher bioaccumulated trace elements compared to prawn. With the exception of Ni and Cd, the estimated daily intakes (EDI) for both adults and children were below the recommended daily allowance (RDA), which exhibits that other trace elements do not cause harm to human health. Furthermore, the hazard index (HI) and total hazard quotient (THQ) were also found to be within acceptable limits, taking into account the higher vulnerability of children to toxicity compared to adults. Notably, the HI suggested that children were approximately four times more susceptible to both carcinogenic and non-carcinogenic effects compared to adults. Ultimately, the levels of carcinogenic risk were deemed acceptable, despite the estimated values suggesting susceptibility to adverse effects in both adults and children. This study concluded that fish and shellfish may not pose a health risk to consumers, highlighting the importance of further monitoring of trace elements in the catchment area.

Simultaneous microwave digestion for total arsenic and inorganic arsenic in local shrimp and prawn commodities of Brunei Darussalam for regulatory and safety monitoring.

The data gap in food safety regulations have created misinformation leading to the rejection of commodities for trade. The evidence presented is the local regulation of arsenic in sea produce which is based on total arsenic, tAs, instead of toxic inorganic arsenic, iAs. Furthermore, tAs data in animal origin seafood has been widely proven to be dominated by the non-toxic Arsenobetaine, AsB. Therefore, if arsenic regulatory limit was set based only on tAs without reference to iAs data, seafood products might be wrongfully rejected for trade because of non-compliance to tAs limit. We provided analysis of tAs and iAs of 14 local prawn and shrimp commodities from three shrimp/prawn sector namely aquaculture (n = 3), capture (n = 5) and processed (n = 6) using effective extraction, as well as, a fit-for-purpose analytical method for iAs. A HVG-AAS method was developed and validated for iAs with LoQ of 1.6 ppb, analytical range of 0-6 ppb, repeatability RSDr of 0.5-3.1 %, coefficient of determination R2 of 0.9975, and percentage recovery of 90.9 %, while an existing method using ICP-MS was used to verify the tAs. Based on the AOAC Official Method 999.10 2005 with minor adjustments, seafood samples were digested with concentrated nitric acid and hydrogen peroxide under pressure in a closed vessel heated by a microwave digester. An additional step for iAs determination was necessary to ensure compatibility in HVG-AAS analysis. Further subdivision of the aquaculture and capture samples was done by dividing them into 3 fractions, namely head, flesh and peel. Comparison of tAs in all the three fractions indicated that for aquaculture sector, the highest tAs were found in the flesh (2nd highest in % weight) whereas for the capture sector, the highest amount of tAs correlated with the highest % weight of the fraction. On regulatory aspects, speciation analysis on the iAs indicated samples with quantifiable iAs value were in-compliance despite tAs were initially found to be higher than the national limits. Risk assessment of iAs indicated there were no risk for human daily intake based on the BDML0.5 value of 3.0 µg/kg b.w per day for an average 70 kg man. All findings concluded the need for doing arsenic speciation analysis of iAs along with tAs for routine monitoring of prawn/shrimp samples and to revise the local limits from tAs to iAs particularly for seafood commodities.

Applications of high-intensity ultrasound on shrimp: Potential, constraints, and prospects in the extraction and retrieval of bioactive compounds, safety, and quality.

The global shrimp market holds substantial prominence within the food industry, registering a significant USD 24.7 billion in worldwide exportation in 2020. However, the production of a safe and high-quality product requires consideration of various factors, including the potential for allergenic reactions, occurrences of foodborne outbreaks, and risks of spoilage. Additionally, the exploration of the recovery of bioactive compounds (e.g., astaxanthin [AX], polyunsaturated fatty acids, and polysaccharides) from shrimp waste demands focused attention. Within this framework, this review seeks to comprehend and assess the utilization of high-intensity ultrasound (HIUS), both as a standalone method and combined with other technologies, within the shrimp industry. The objective is to evaluate its applications, limitations, and prospects, with a specific emphasis on delineating the impact of sonication parameters (e.g., power, time, and temperature) on various applications. This includes an examination of undesirable effects and identifying areas of interest for current and prospective research. HIUS has demonstrated promise in enhancing the extraction of bioactive compounds, such as AX, lipids, and chitin, while concurrently addressing concerns such as allergen reduction (e.g., tropomyosin), inactivation of pathogens (e.g., Vibrio parahaemolyticus), and quality improvement, manifesting in reduced melanosis scores and improved peelability. Nonetheless, potential impediments, particularly related to oxidation processes, especially those associated with lipids, pose a hindrance to its widespread implementation, potentially impacting texture properties. Consequently, further optimization studies remain imperative. Moreover, novel applications of sonication in shrimp processing, including brining, thawing, and drying, represent a promising avenue for expanding the utilization of HIUS in the shrimp industry.

Estimate of Growth Parameters of Penaeus kerathurus (Forskäl, 1775) (Crustacea, Penaeidae) in the Northern Adriatic Sea.

Crustacean fisheries are gaining prominence globally amid a decline in finfish stocks. Some decapod crustacean species have experienced increased landings in response to shifting market demands and environmental dynamics. Notably, the caramote prawn (Penaeus kerathurus-Forskål, 1775) in the northern Adriatic Sea, Geographical Sub Area (GSA) 17, has risen in both landings and economic importance in recent years. However, despite its significance, comprehensive information on fishery-dependent data, age, and growth in this region remains lacking. To address this gap, this study employs modal progression analysis and the ELEFAN approach, utilizing the "TropFishR" R package and newly developed functions, including bootstrapping procedures. These advancements aim to overcome issues identified in previous versions and enhance the accuracy and reliability of age and growth estimations. The study leverages one year of monthly length-frequency distributions (LFDs) collected from commercial bottom trawls in the northern Adriatic Sea. The results of the analysis confirm the presence of sexual dimorphism in the caramote prawn species, with females exhibiting faster growth rates compared to males. Additionally, the growth performance index supports this observation, further underscoring the importance of accounting for sexual dimorphism in growth modeling and fisheries management strategies. By contributing to a growing body of knowledge on the growth dynamics of the caramote prawn, this study provides valuable insights for sustainable fisheries management in the northern Adriatic Sea. Understanding the age and growth patterns of key crustacean species is essential for developing effective conservation measures and ensuring the long-term health and productivity of marine ecosystems. The findings of this study serve as a foundation for informed decision-making and proactive management practices aimed at preserving the ecological integrity and economic viability of crustacean fisheries in the region.

Differential expression of neuropeptide F in the digestive organs of female freshwater prawn, Macrobrachium rosenbergii, during the ovarian cycle.

Neuropeptide F is a key hormone that controls feeding in invertebrates, including decapod crustaceans. We investigated the differential expression of Macrobrachium rosenbergii neuropeptide F (MrNPF) in the digestive organs of female prawns, M. rosenbergii, during the ovarian cycle. By using RT-qPCR, the expression of MrNPF mRNA in the esophagus (ESO), cardia (CD), and pylorus (PY) of the foregut (FG) gradually increased from stage II and peaked at stage III. In the midgut (MG), hindgut (HG), and hepatopancreas (HP), MrNPF mRNA increased from stage I, reaching a maximal level at stage II, and declined by about half at stages III and IV (P < 0.05). In the ESO, CD, and PY, strong MrNPF-immunoreactivities were seen in the epithelium, muscle, and lamina propria. Intense MrNPF-ir was found in the MG cells and the muscular layer. In the HG, MrNPF-ir was detected in the epithelium of the villi and gland regions, while MrNPF-ir was also more intense in the F-, R-, and B-cells in the HP. However, we found little colocalization between the MrNPF and PGP9.5/ChAT in digestive tissues, implying that most of the positive cells might not be neurons but could be digestive tract-associated endocrine cells that produce and secrete MrNPF to control digestive organ functions in feeding and utilizing feed. Taken together, our first findings indicated that MrNPF was differentially expressed in digestive organs in correlation with the ovarian cycle, suggesting an important link between MrNPF, the physiology of various digestive organs in feeding, and possibly ovarian maturation in female M. rosenbergii.

Polychlorinated dibenzodioxins/furans and dioxin-like polychlorinated biphenyls in fish and crustaceans of a recreationally fished estuary, following targeted remediation.

Polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) are a suite of harmful chemicals (hereafter collectively referred to as 'dioxins'), and their emission into aquatic habitats leads to persistent contamination of sediments, aquatic food-webs, and seafoods. Quantifying contaminant levels in seafood species is important for the ongoing management of exposure risk by fishers, particularly after any remediation actions. We present dioxin concentrations in four seafood species (Yellowfin Bream Acanthopagrus australis, Sea Mullet Mugil cephalus, Eastern School Prawn Metapenaeus macleayi, and Eastern King Prawn Penaeus plebejus) in a recreationally fished estuary, in relation to a contaminated site that has undergone a remediation process, partially removing contaminated sediments (Homebush Bay, Port Jackson, New South Wales, Australia). Dioxin concentrations in these species were measured before (2005/6) and after (2015/16) remediation at a range of locations in and around the remediated site. Dioxin concentrations and congener profiles differed substantially among taxa, and concentrations were frequently higher than Australian screening criteria. The two prawn species showed evidence of a decline in dioxin concentrations after remediation, but the fish species only showed a declining dioxin concentration with distance from the contaminated site (not between periods). There were some minor changes in the congener profile for some species following remediation. While there was evidence for greatly reduced dioxin concentrations in prawn species following remediation, the complex patterns for fish were likely affected by environmental changes, species-specific and temporal changes in lipid content, and animal movement patterns. Future monitoring may aid interpretation of the patterns and modelling of exposure risk associated with seafood consumption into the future.

Transcriptome analysis of reproductive tract tissues of male river prawn Macrobrachium americanum.

BACKGROUND: The river prawn, Macrobrachium americanum (M. americanum), is one of the largest prawns of the genus in Latin America and is an amphidromous species distributed along the Pacific coast of America. This prawn has commercial value due to its size and taste, making it a good option for aquaculture production. Its culture has been attempted in ponds and concrete tanks, but no successful technique can still support commercial production. Understanding the mechanisms that regulate reproduction at the molecular level is very important. This knowledge can provide tools for manipulating transcripts, which could increase the number or size of animals in the culture. Our understanding of the mechanism that regulates the reproduction of M. americanum at the molecular level is limited. AIM: Perform and analyze the transcriptome assembly of the testes, vas deferens, and terminal ampulla of M. americanum. to provide new molecular information about its reproduction. METHODS AND RESULTS: The cDNA library was constructed and sequenced for each tissue to identify novel transcripts. A combined transcriptome with the three tissues was assembled using Trinity software. Unigenes were annotated using BLASTx and BLAST2GO. The transcriptome assembly generated 1,059,447 unigenes, of which 7222 genes had significant hits (e-value < 1 × 10-5) when compared against the Swiss-Prot database. Around 75 genes were related to sex determination, testis development, spermatogenesis, spermiogenesis, fertilization, maturation of testicular cells, neuropeptides, hormones, hormone receptors, and/or embryogenesis. CONCLUSIONS: These results provide new molecular information about M. americanum reproduction, representing a reference point for further genetic studies of this species.

Depletion kinetics of semicarbazide in giant river prawn (Macrobrachium rosenbergii) following nitrofurazone oral administration and its occurrence in an aquaculture farm.

Semicarbazide (SEM), a marker residue used to monitor the use of prohibited drug nitrofurazone (NFZ), is commonly found in wild crustaceans, implying the natural origin. However, the difference between endogenous and exogenous SEM has rarely been investigated. So, tissue-bound SEM was determined in samples collected from giant river prawns cultured in an aquaculture farm and in samples from an experiment where giant river prawns were fed twice a day with NFZ at 30 mg/kg for 5 days. At day 10 of drug withdrawal, muscle SEM of the NFZ-fed prawn was 17.78 ng/g and depleted to 1.18 ng/g at day 90 (half-life 20.31 days) which was significantly higher than the control prawn (usually ≤ 0.1 ng/g). In contrast, the average SEM in the shell was independent of NFZ treatment. SEM was not found in the aquaculture farm samples, implying that the SEM in cultured prawn did not originate from SEM contamination.

Metabolomic assessment of African snail (Achatina fulica) meal on growth performance of giant river prawn (Macrobrachium rosenbergii).

This study aimed to investigate the effects of replacing fishmeal (FM) with African giant snail (Achatina fulica) meal (SM) on the growth performance of giant river prawn (Macrobrachium rosenbergii), as well as to analyze the associated metabolomic changes. Six diets were formulated, replacing FM with SM at different inclusion levels ranging from 0 % to 100 %. Growth performance and feed conversion ratio of prawns fed diets with FM replaced by SM up to 80 % were not significantly different from control. In contrast, significantly decreased growth performance and higher feed conversion ratio (FCR) occurred with diets containing 100 % SM. To gain insights into the metabolic regulation of prawns fed different diets, a 1H NMR metabolomics approach was used to assess the metabolic changes in prawns fed diets containing 0 % and 80 % SM. The results revealed up-regulated metabolites significantly involved in several metabolic pathways, including alanine, aspartate, and glutamate metabolism; citrate cycle (TCA cycle); aminoacyl-tRNA biosynthesis; and valine, leucine, and isoleucine biosynthesis. These findings imply that including SM in the diet might modulate the regulation of muscle amino acids and tRNA synthesis, suggesting a potential impact on protein biosynthesis mechanisms. Additionally, alterations in the TCA cycle may reflect changes in carbon utilization, potentially contributing to the growth performance of giant river prawns when fishmeal is replaced with SM without adversely affecting their growth. In conclusion, this study demonstrated that SM could be a promising alternative protein source in aquafeed. The metabolomic approach provides valuable insights into the metabolic changes in prawns fed different diets, aiding in the development of more effective aquafeeds in the future. The study's limitations, such as the simplified diet formulation and the limited scope of the metabolomic analysis, were acknowledged and discussed, highlighting the need for further research to build upon these findings.

Electro-flocculation of aquaculture wastewater microalgal communities reduces nutrient loading.

Land-based aquaculture provides dietary protein to the world's population in a sustainable way, but issues related to release of nitrogen rich wastewater limits its expansion. Sedimentation of naturally occurring microalgae that assimilate excess nitrogen, is slow and land intensive. Electro-flocculation, used in wastewater treatment processes, is a potential alternative for aquaculture. Trials of different electro-flocculation configurations applied to three prawn farm pondwater samples containing varying microalgal assemblages are reported. In 64 % of trials, electro-flocculation reduced total nitrogen (TN) and dissolved inorganic nitrogen (DIN) loads within regulatory limits.TN was reduced up to 83.2 % (10.93 to 1.83 mg.L-1) within 20 mins in stationary water, and DIN to 90.6 % (3.19 to 0.30 mg.L-1) in 102 mins trials in flowing water. Bellerochea andGloeocapsa spp. were dominant in wastewater. The role of microalgal community composition on flocculation is discussed, including evidence Bellerocheapromotes flocculation. This study confirmed electro-flocculation quickly reduces TN and DIN.

New occurrences, mean infestation intensity and prevalence of parasitic isopods (Isopoda, Cymothoida, Bopyridae) associated with Macrobrachium amazonicum (Decapoda, Palaemonidae) from the mouth of the Amazon River / Novas ocorrências, intensidade média de infestação e prevalência de isópodes parasitas (Isopoda, Cymothoida, Bopyridae) associados a Macrobrachium amazonicum da foz do rio Amazonas

Abstract The Amazon prawn or Macrobrachium amazonicum (Heller, 1862) is widely distributed in South America, occurring in the Orinoco and Amazon rivers, and forms an important source of income for riverside families. This prawn hosts crustacean ectoparasites of the genus Probopyrus (Giard & Bonnier, 1888) (Bopyridae) that infest its gill cavity. The aim of the present study was to report new occurrences of Probopyrus in Amazon prawns caught in the Amazon River. Macrobrachium amazonicum prawns were collected between May 2017 and April 2018, and again from July 2021 to May 2022 in the regions of Ilha de Santana and Rio Mazagão, state of Amapá, Brazil. Among the 5,179 prawn specimens caught, 133 were parasitized by the ectoparasites Probopyrus pandalicola (Packard, 1879), Probopyrus bithynis (Richardson, 1904), Probopyrus floridensis (Richardson, 1904) and Probopyrus palaemoni (Lemos de Castro & Brasil Lima, 1974). These occurrences of P. floridensis and P. palaemoni in M. amazonicum were the first records of this on the northern coast of Brazil. These four ectoparasites are not limited to specific host species or genera, as observed in this study, which reports four species of Probopyrus infesting M. amazonicum.

Resumo O camarão-da-amazônia ou Macrobrachium amazonicum (Heller, 1862) é amplamente distribuído na América do Sul, ocorrendo nos rios Orinoco e Amazonas, importante fonte renda de familias riberinhas. Esse camarão é hospedeiro de ectoparasitas crustáceos do gênero Probopyrus (Giard & Bonnier, 1888) (Bopyridae) que infestam a cavidade branquial da espécie. O presente estudo tem o objetivo de relatar novas ocorrências de ectopasitas do gênero Probopyrus no camarão-da-amazônia, capturados no rio Amazonas. Macrobrachium amazonicum foram coletados no período de maio de 2017 e abril de 2018, e novamente de julho de 2021 a maio de 2022, nas regiões da Ilha de Santana e Rio Mazagão, estado do Amapá, Brasil. Entre 5.179 exemplares de camarões capturados, 133 foram parasitados sendo quatro pelos ectoparasitas Probopyrus pandalicola (Packard, 1879), Probopyrus bithynis (Richardson, 1904), Probopyrus floridensis (Richardson, 1904) e Probopyrus palaemoni (Lemos de Castro & Brasil Lima, 1974). Registrado pela primeira vez a ocorrência no M. amazonicum por P. floridensis e P. palaemoni no litoral norte do Brasil. Esses quatro ectoparasitos não se limitam a espécies ou gêneros hospedeiros específicos, observados nesse estudo que relata quatro espécies de Probopyrus infestando M. amazonicum.

In silico prospecting of the mtDNA of Macrobrachium amazonicum from transcriptome data.

BACKGROUND: Macrobrachium amazonicum is a freshwater prawn widely distributed in South America that is undergoing speciation, so the denomination "M. amazonicum complex" is used for it. The mitochondrial cytochrome c oxidase subunit I (COI) gene has been used to elucidate this speciation, but heteroplasmies and pseudogenes have been recorded, making separation difficult. Obtaining genes from cDNA (RNA) rather than genomic DNA is an effective tool to mitigate those two types of occurrences. The aim of this study was to assemble in silico the mitochondrial DNA (mtDNA) of the Amazonian coastal population of M. amazonicum inhabiting the state of Pará. RESULTS: Sequences were obtained from the prawn's transcriptome using the de novo approach. Six libraries of cDNA from the androgen gland, hepatopancreas, and muscle tissue were used. The mtDNA of M. amazonicum was 14,960 bp in length. It contained 13 protein-coding genes, 21 complete transfer RNAs, and the 12S and 16S subunits of ribosomal RNA. All regions were found on the light strand except tRNAGln, which was on the heavy strand. The control region (D-loop) was not recovered, making for a gap of 793 bp. The cladogram showed the formation of the well-defined Macrobrachium clade, with high support value in the established branches (91-100). The three-dimensional spatial conformation of the mtDNA-encoded proteins showed that most of them were mainly composed of major α-helices that typically shows in those proteins inserted in the membrane (mitochondrial). CONCLUSIONS: It was possible to assemble a large part of the mitochondrial genome of M. amazonicum in silico using data from other genomes deposited in GenBank and to validate it through the similarities between its COI and 16S genes and those from animals of the same region deposited in GenBank. Depositing the M. amazonicum mtDNA sequences in GenBank may help solve the taxonomic problems recorded for the species, in addition to providing complete sequences of candidate coding genes for use as biomarkers in ecological studies.

Occurrence and risk characterization of per- and polyfluoroalkyl substances in seafood from the Persian Gulf.

Potential exposure to 14 per- and polyfluoroalkyl substances (PFAS) through seafood consumption was investigated in widely consumed seafood (Platycephalus indicus, Lethrinus nebulosus, and Penaeus semisulcatus) from the Persian Gulf. A total of 61 samples of fish and prawns were purchased from local fishers at Bushehr port (Persian Gulf, South-West of Iran) and were analyzed for PFAS compounds. In addition, potential factors influencing factor of PFAS bioaccumulation in fish and invertebrates such as age, sex, and habitat, were investigated. Æ©PFAS concentrations were in the range of 2.3- 6.1 ng/g-d.w (mean = 3.9 ± 1.9) in studied species which are equal to 0.46-1.2 ng/g-w.w according to their conversion factor. Perfluorooctane sulfonic acid (PFOS) was the most abundant perfluorinated compound in studied organisms and tissues. The results of correlation analysis showed that the bioaccumulation of PFAS in aquatic organisms is significantly correlated to the length of the compound's carbon chain, the identity of anionic group, and organism's age, sex, and habitant. The risk assessment using hazard index calculation and Monte-Carlo simulation indicated that weekly consumption of prawn and fish fillets does not pose a health risk to adults but might threaten children's health. However, the risk posed by PFAS exposure via entire fish or fish liver intake is an important issue for wild marine mammals (i.e., dolphins). So, accurate and routine monitoring of PFAS in aquatic environments seems mandatory to preserve wildlife and human health in the Persian Gulf.

Multi-Effects of Acute Salinity Stress on Osmoregulation, Physiological Metabolism, Antioxidant Capacity, Immunity, and Apoptosis in Macrobrachium rosenbergii.

Salinity stress can trigger a series of physiological changes. However, the mechanism underlying the response to acute salinity stress in Macrobrachium rosenbergii remains poorly understood. In this study, osmoregulation, physiological metabolism, antioxidant capacity, and apoptosis were examined over 96 h of acute salinity stress. Hemolymph osmolality increased with increasing salinity. After 48 h of salinity exposure, the glucose, triglycerides, total protein, and total cholesterol contents in two salinity stress groups (13 and 26‱ salinity) were significantly lower than those in the 0‱ salinity group. The highest levels of these parameters were detected at 6 h; however, superoxide dismutase (SOD), total antioxidant capacity (T-AOC), and malondialdehyde (MDA) were the lowest at 96 h in the 13‱ salinity group. The activity of immunity-related enzyme alkaline phosphatase (AKP) showed a decreasing trend with increasing salinity and remained at a low level in the 26‱ salinity group throughout the experiment. No significant differences were observed in aspartate aminotransferase (AST), alanine aminotransferase (ALT), or lysozyme (LZM) among the three treatments at 96 h. After 96 h of salinity treatments, the gill filament diameter significantly decreased, and a more pronounced terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive signal was detected in the 13‱ and 26‱ groups compared to that in the 0‱ group. Expression levels of apoptosis-related genes, including Cysteine-aspartic acid protease 3 (Caspase 3), Cysteine-aspartic acid protease 8 (Caspase 8), Cytochrome c (Cyt-c), tumor suppressor gene (P53), Nuclear factor kappa-B (NF-κB), and B cell lymphoma 2 ovarian killer (Bok) were significantly higher in the 26‱ salinity group than in the other groups at 24 h, but lower than those in the 0‱ salinity group at 96 h. Cyt-c and P53 levels exhibited a significantly positive relationship with MDA, AST, and LZM activity during salinity stress. In the 13‱ salinity group, Bok expression was significantly correlated with SOD, T-AOC, AKP, acid phosphatase, and LZM activity, whereas in the 26‱ group, the AST content was positively correlated with Caspase 8, Cyt-c, and P53 expression. A significant negative relationship was observed between Caspase 3 expression and catalase (CAT) activity. These findings provide insight into the mechanisms underlying the response to acute salinity stress and will contribute to improving M. rosenbergii aquaculture and management practices.

Utilisation of probiotics for disease management in giant freshwater prawn (Macrobrachium rosenbergii): Administration methods, antagonistic effects and immune response.

The giant freshwater prawn (Macrobrachium rosenbergii) is a high-yielding prawn variety well-received worldwide due to its ability to adapt to freshwater culture systems. Macrobrachium rosenbergii is an alternative to shrimp typically obtained from marine and brackish aquaculture systems. However, the use of intensive culture systems can lead to disease outbreaks, particularly in larval and post-larval stages, caused by pathogenic agents such as viruses, bacteria, fungi, yeasts and protozoans. White tail disease (viral), white spot syndrome (viral) and bacterial necrosis are examples of economically significant diseases. Given the increasing antibiotic resistance of disease-causing microorganisms, probiotics have emerged as promising alternatives for disease control. Probiotics are live active microbes that are introduced into a target host in an adequate number or dose to promote its health. In the present paper, we first discuss the diseases that occur in M. rosenbergii production, followed by an in-depth discussion on probiotics. We elaborate on the common methods of probiotics administration and explain the beneficial health effects of probiotics as immunity enhancers. Moreover, we discuss the antagonistic effects of probiotics on pathogenic microorganisms. Altogether, this paper provides a comprehensive overview of disease control in M. rosenbergii aquaculture through the use of probiotics, which could enhance the sustainability of prawn culture.