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Farmed freshwater prawn (Macrobrachium rosenbergii) and black tiger shrimp (Penaeus monodon) comprise a significant portion of Bangladesh's seafood exports, raising concerns about their environmental impacts. Freshwater prawn farms, which require a relatively high amount of feed supply, release 1.0 MT CO2-equivalents/year, equating to 18.8 kg CO2e/MT prawn, contributing significantly to global warming and climate change risks. Integrated Multi-Trophic Aquaculture (IMTA) offers an alternative farming method to conventional prawn farming systems, as it minimizes greenhouse gas (GHG) emissions and climate change impacts. Systematically reviewing 112 scientific articles on IMTA, this article offers recommendations for adopting IMTA to promote sustainable freshwater prawn farming in Bangladesh. IMTA is undergoing extensive experimentation and practice in many parts of the world, offering economic benefits, social acceptability, and environmental sustainability. In addition to native prawn species, various indigenous organic extractive freshwater mollusks, and inorganic extractive plants are available which can seamlessly be used to tailor the IMTA system. Extractive organisms, including aquatic mollusks and plants within prawn farms, can capture blue carbon effectively lowering GHG emissions and helping mitigate climate change impacts. Aquatic mollusks offer feed for fish and livestock, while aquatic plants serve as a dual food source and contribute to compost manure production for crop fields. Research on IMTA in Bangladesh was primarily experimented on finfish in freshwater ponds, with the absence of studies on IMTA in prawn farms. This necessitates conducting research at the prawn farmer level to understand the production of extractive aquatic mollusk and plants alongside prawn in the prawn-producing regions of southwestern Bangladesh. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to evaluate the status, resource use, and challenges of the capture-based hatchery of black tiger shrimp (Penaeus monodon) (BTS). Methods: Data was obtained through the investigation of 15 broodstock fishing boats and 60 capture-based BTS broodstock hatcheries. Resource use index (RUI) of the capture-based BTS hatchery, calculated from 1,000 female brooders to produce 15-day-old post-larvae (PL15) (production efficiency of PL15, or PEPL15), was analysed. Results: The results indicated that the fishing boats captured an average of 5,900 brooders.boat-1.year-1, 20,856 kg of by catch.boat-1.year-1, and the PE-PL15 production of 937 million for 1,000 female brooders. In the hatchery stage, the use of larger body weight female brooders had benefits in terms of higher survival rate and better efficiency of labour use, Artemia cyst, and probiotic products, but it reduced the efficiency use of chemicals, pellets, and total tank volume of the hatchery. Discussion: There is increasing use of domesticated brooder sources, but wildcaught brooders still play an important role in producing low-cost PL15 for traditional shrimp farming systems, accounting for most farmed BTS production. Therefore, the certification of good practices should be implemented to capture-based BTS hatcheries for the reasonable use of this brooder resource to sustain BTS farming in Vietnam. [ABSTRACT FROM AUTHOR]

To investigate the different mechanisms of Penaeus monodon in response to acute and chronic hypotonic stress, RNA sequencing technology was employed to profile the gene expression patterns in the gill, hepatopancreas, and hemocyte at 0, 6, 48, and 72 h post acute hypotonic stress treatment (with salinity immediately decreased from 20 psu to 4 psu) and at 0, 2, 10, 15 days during chronic hypotonic stress treatment (with salinity gradually decreased from 20 psu to 4 psu). The control group (SC) was maintained at a constant salinity of 20 psu. Differentially expressed genes (DEGs) were identified, followed by further validation using real-time quantitative reverse transcription PCR (RTqPCR). A total of 34,217 genes were expressed through sequencing. Compared with the control group, 8,503 DEGs were identified in the acute hypotonic stress group, comprising 3,266 up-regulated and 5,237 down-regulated genes. In the chronic hypotonic stress group, 8,900 DEGs were detected, including 3,019 up-regulated and 5,881 down-regulated genes. Gene Ontology (GO) functional annotation analysis indicated that DEGs were primarily enriched in biological processes such as cellular and metabolic processes, cellular components like membrane and other cellular components, and molecular functions including structural binding and catalytic activity. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis indicated that DEGs were predominantly concentrated in five major pathways: metabolism, genetic information processing, environmental information processing, cellular processes, and biological systems. These pathways encompassed antigen processing and presentation, the NOD-like receptor signaling pathway, the Toll-like receptor signaling and cell apoptosis. The RT-qPCR validation of 11 DEGs (hsp70, hsp90, nlrp3, mincle, nlrp12, tlr4, myd88, imd, casp7, casp9 and toll) demonstrated that the trends observed in the quantitative results were consistent with those from the transcriptome analysis, thereby validating the reliability of transcriptome sequencing data. This study identified that hypotonic stress triggers physiological responses in P. monodon to both acute and chronic hypotonic conditions, offering valuable insights into the expression patterns of functional genes in the gills, hepatopancreas, and hemocytes of P. monodon under such stress. These findings provide foundational data and a theoretical basis for further research into the regulatory mechanism of P. monodon in response to hypotonic stress. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the impact of adding fermented herbal extracts (FHE) derived from mulberry leaf (Morus alba), Javanese turmeric (Curcuma xanthorrhiza), and fingerroot (Boesenbergia rotunda) to the diet of tiger shrimp (Penaeus monodon) on their growth, moulting performance, feed efficiency, and nutrient retention. The main feed used in this trial was a commercially manufactured pellet; then, five different doses of FHE supplementation were used: 0 mL/kg feed (P0, control), 50 mL/kg feed (P1), 100 mL/kg feed (P2), 150 mL/kg feed (P3), and 200 mL/kg feed (P4). Weight gain, average daily gain, and length gain of shrimps fed P2 were significantly higher than that of those fed the control diet. A similar result was observed in moulting performance. The application of P2 showed superior results in enhancing the feed efficiency of cultured shrimp. Thus, the protein and energy retention of P. monodon was significantly better in P2 treatment groups. P0 had the lowest crude protein, while shrimp on the P2 and P3 diets had the highest crude protein content of any treatment group. Crude lipid content was lower in shrimp fed diets supplemented with FHE compared to those fed the control diet. In addition, higher energy contents were found in P1 and P2 treatment groups. Based on the findings, it is recommended that the juvenile tiger shrimp diet contain 100 mL/kg of FHE for the best effects. [ABSTRACT FROM AUTHOR]

Biological invasions are among the major stressors on aquatic ecosystems. It can significantly affect species distribution and native biodiversity. Penaeus monodon invasions are frequently reported worldwide, leading to the establishment of several breeding populations. P. monodon was first recorded and morphologically identified in the Mediterranean Sea in Egypt in 2016. The current investigation aimed to assess the genetic diversity and origin of a P. monodon population from the Mediterranean Sea, Egypt, and to evaluate the genetic diversity of P. monodon populations worldwide using two different mitochondrial barcode regions, cytochrome c oxidase subunit I (COI) and 16S rRNA. Different P. monodon populations with Indo-Pacific and Atlantic origins were included for these purposes. Based on the COI, 16 haplotypes were recorded in nine P. monodon populations, with 45 polymorphic sites. High haplotype diversity (Hd = 0.7575) and high nucleotide diversity (π = 0.0261) were also recorded. Based on 16S rRNA, 37 haplotypes were recorded in seven P. monodon populations, with 72 polymorphic sites, high haplotype diversity (Hd = 0.9838), and high nucleotide diversity (π = 0.0985). The populations of P. monodon within its species range (of Indo-Pacific and Atlantic origins) shared many haplotypes, indicating shared lineages. Barrier analysis has divided the studied populations into groups in which Egypt was grouped with populations of Atlantic origin (based on COI and 16S rRNA) and supported with evidence of the Atlantic origin of the Egyptian population. This study showed that the Suez Canal is not the inevitable route for this species to invade the Mediterranean; therefore, precision must be exercised when determining the route of entry of any species into the Mediterranean Sea. The frequent introductions/invasions of the P. monodon population significantly contributed to the observed patterns of genetic diversity and favored its ability to adapt, colonize, and expand. [ABSTRACT FROM AUTHOR]

Penaeus monodon is one of the world's most important aquaculture species, with its host-associated microbial community playing a crucial role in its growth, metabolism, immune response, and adaptation. In our study, we utilized Illumina high-throughput sequencing to investigate the composition, structure, and function of the intestinal microbial communities of P. monodon from two different regions in Guangdong. Our results identified 176 phyla across both populations, with Proteobacteria and Firmicutes being predominant. Furthermore, we identified 3095 genera, with Photobacterium, Vibrio, and Aliiroseovarius being the most dominant. Functional gene analysis based on KEGG data indicated that the carbohydrate metabolism and amino acid metabolism were significant at the secondary metabolic pathway level. The eggNOG functional annotation revealed that the genes involved in replication, recombination, and repair are of paramount importance. The CAZy annotation results indicated that Glycoside Hydrolases (GH) have the highest abundance. The Pfam annotation analysis showed that the two most prevalent domains are P-loop NTPase and NADP Rossmann. Our investigation provides a reference for species-level and functional-level analyses of the intestinal microbiota of P. monodon, contributing valuable insights into its microbial ecology. [ABSTRACT FROM AUTHOR]

This study assessed the performance of domesticated tiger shrimp Penaeus monodon postlarvae and mud crab Scylla paramamosain co‐cultured in 90 extensive rice‐shrimp ponds in the Mekong River Delta of Vietnam from 2022 to Sep 2023. Limited supplementary feeding was applied for only 20% of the studied ponds. Results show that ponds stocked with domesticated postlarvae produced significantly larger shrimps at harvest and had better postlarvae usage efficiency (P < 0.05) compared with those stocked with older postlarvae produced by wild‐caught broodstock. Furthermore, a combination of stocking domesticated postlarvae and using organic fertilizer for pond preparation and during the crop was found to significantly improve productivity by 28% and final harvest size by 67% (P < 0.05). Larger shrimps fetched 54% higher farm‐gate prices, thus significantly increasing gross revenue for farmers. Co‐culture of mud crab in rice‐shrimp ponds at low densities (0.2–0.7 pcs/m2) was popular and profitable. Productivity was 116–187 kg/ha/crop with a profit margin up to 92.8%. Income from mud crab was very similar to that from shrimp. The results of this study suggest that domesticated postlarvae of P. monodon should be used for stocking extensive systems, preferably in combination of using organic fertilizer to enhance natural foods. Further improvement of income and profit can be achieved if more attention is paid on crablet quality and quality improvement. [ABSTRACT FROM AUTHOR]

Family Parvoviridae consists of small, non-enveloped viruses with linear, single-stranded DNA genomes of approximately 4-6 kilobases, subdivided into three subfamilies, Parvovirinae, Densovirinae, and Hamaparvovirinae, and unassigned genus Metalloincertoparvovirus. Parvoviruses of aquatic animals infect crustaceans, mollusks, and finfish. This review describes these parvoviruses, which are highly host-specific and associated with mass morbidity and mortality in both farmed and wild aquatic animals. They include Cherax quadricarinatus densovirus (CqDV) in freshwater crayfish in Queensland, Australia; sea star-associated densovirus (SSaDV) in sunflower sea star on the Northeastern Pacific Coast; Clinch densovirus 1 in freshwater mussels in the Clinch River, Virginia, and Tennessee, USA, in subfamily Densovirinae; hepatopancreatic parvovirus (HPV) and infectious hypodermal and hematopoietic necrosis virus (IHHNV) in farmed shrimp worldwide; Syngnathid ichthamaparvovirus 1 in gulf pipefish in the Gulf of Mexico and parts of South America; tilapia parvovirus (TiPV) in farmed tilapia in China, Thailand, and India, in the subfamily Hamaparvovirinae; and Penaeus monodon metallodensovirus (PmMDV) in Vietnamese P. monodon, in unassigned genus Metalloincertoparvovirus. Also included in the family Parvoviridae are novel parvoviruses detected in both diseased and healthy animals using metagenomic sequencing, such as zander parvovirus from zander in Hungary and salmon parvovirus from sockeye salmon smolts in British Columbia, Canada. [ABSTRACT FROM AUTHOR]

White spot syndrome virus (WSSV) presents a considerable peril to the aquaculture sector, leading to notable financial consequences on a global scale. Previous studies have identified hub proteins, including WSSV051 and WSSV517, as essential binding elements in the protein interaction network of WSSV. This work further investigates the functional structures and potential applications of WSSV hub complexes in managing WSSV infection. Using computational methodologies, we have successfully generated comprehensive three-dimensional (3D) representations of hub proteins along with their three mutual binding counterparts, elucidating crucial interaction locations. The results of our study indicate that the WSSV051 hub protein demonstrates higher binding energy than WSSV517. Moreover, a unique motif, denoted as "S-S-x(5)-S-x(2)-P," was discovered among the binding proteins. This pattern perhaps contributes to the detection of partners by the hub proteins of WSSV. An antiviral strategy targeting WSSV hub proteins was demonstrated through the oral administration of dual hub double-stranded RNAs to the black tiger shrimp, Penaeus monodon, followed by a challenge assay. The findings demonstrate a decrease in shrimp mortality and a cessation of WSSV multiplication. In conclusion, our research unveils the structural features and dynamic interactions of hub complexes, shedding light on their significance in the WSSV protein network. This highlights the potential of hub protein-based interventions to mitigate the impact of WSSV infection in aquaculture. [ABSTRACT FROM AUTHOR]

The tiger shrimp (Penaeus monodon Fabicius, 1798) is a popular Indonesian fishery product with high market value both domestically and internationally. Its high nutritional value makes it a valuable product that is in high demand. Along with increased production, various challenges appeared in management and feed quality aspects. Multi-enzymes are one method for increasing the tiger shrimp productivity. This study aimed to identify the dose of multi-enzymes in the feed that leads to an optimal growth performance, and optimum activity of digestive enzymes (amylase, protease, lipase), as well as improving the essential amino acids index in the shrimp body. This study used a completely randomized design (CRD) with 4 treatments and 3 replications each, thus 12 experimental units were applied. The treatments used were A at 0%/kg feed, B at 40%, C at 60%, and D at 80%/kg feed. The experimental animal was the tiger shrimp with a mean weight of 0.07g/ ind. The shrimps were reared in the hatchery laboratorium of the Marine Science and Fishery Faculty, Hasanuddin University, Makassar. The parameters examined were essential amino acid index (EAAI), essential amino acid score (EAAS), enzyme type activity, specific growth rate (SGR), relative weight gain (RWG), survival rate (SR), and protein efficiency ratio (PER). The results showed that feed with 80% multienzyme/kg provided the highest EAAI compared to other doses, namely 2.64. In addition, the most EAAS deficiency occurred in methionine EAA, namely 9.29 in multi-enzyme feed with a dose of 40%/kg. SGR, RWG, and PER were not significantly different (P> 0.05), but SR showed a significant difference (P< 0.05). The activity of amylase, protease, and lipase enzymes in the tiger shrimp also increased with the addition of multienzyme doses to the feed. [ABSTRACT FROM AUTHOR]

East Kalimantan has a superior commodity: tiger shrimp (Penaeus monodon). Some of these commodities are marketed to several areas in Samarinda City and to areas outside Samarinda City, namely West Kutai Regency (Barong Tongkok Market). The distribution process uses a cold chain (cool box) system for 12 hours of travel. Long distribution times cause product quality to decrease. This study aims to assess tiger shrimp's quality and handling strategies using a cold chain system at PPI Selili Samarinda City. The quality level is determined using organoleptic testing at points 1 (PPI Selili) and 2 (Pasar Barong Tongkok). The formal safety assessment (FSA) method is used to identify risks in each handling activity, risk assessment associated with tiger shrimp deterioration, risk control, and recommendations to minimize quality degradation. Based on organoleptic tests, the quality of tiger shrimp is included in the category of safe for consumption. Product handling activities included unloading products from ships, moving them to terminals, washing, structuring, packaging in cool boxes, transportation by shipping services, shipping to Melak Pasar Barong Tongkok, unloading from shipping services, and product arrangement. The highest potential risk is handling shipments to Melak Pasar Barong Tongkok, which has 22 potential hazards. Risk mitigation can be applied through socialization and evaluation related to suitable fish handling methods (CPIB) and making operational schedules for cleaning in the product loading and unloading area before and after handling activities. [ABSTRACT FROM AUTHOR]

The reproductive performance of captive tiger shrimp (Penaeus monodon) is a crucial aspect of sustainable aquaculture. This study explores the potential of Cyperus spp. extract components (CE) to enhance the reproductive performance of captive tiger shrimp Penaeus monodon. Our methods involved feeding captive tiger shrimp Penaeus monodon with feed enriched with 0, 300, 400, and 500 µg CE/g Body Weight (BW) over a 60-day rearing period. Eyestalk ablation was used as a positive control. Post-feeding experiments, we observed the shrimp for their reproductive performance. The results were promising: the male broodstock exhibited the highest molting percentage when fed with feed enriched with 400 µg CE/g BW, while females showed the highest molting percentage at 500 µg CE/g BW. The highest percentage of males carrying spermatophores and mating females was observed at 500 µg CE/g BW. Broodstockfed feed enriched with 500 µg CE/g BW produced 337,339 eggs with an average egg diameter of 289.5 µm, yielding 16,175 nauplii. The highest expression of vitellogenin and spermatogenesis was found in the 400-500 µg/g BW range. These findings suggest that the optimal dose of CE for promoting gonadal maturation in captive shrimp broodstock is 400-500 µg/g BW. The potential of this study to increase larval production in aquaculture practices is significant. By utilizing environmentally friendly plant-derived hormones like CE, we can develop more sustainable aquaculture methods, thereby reducing the environmental impact associated with traditional hormone induction strategies. [ABSTRACT FROM AUTHOR]

Simple Summary: The Pacific blue shrimp (Litopenaeus stylirostris) is essential to the global seafood market, but intensive farming has increased disease and reduced genetic diversity. This study aimed to develop microsatellite markers for broodstock management using high-throughput transcriptome sequencing from various tissues. We identified 40 robust markers, revealing significant genetic diversity crucial for sustainable shrimp farming. These markers are valuable for breeding programs and help in the conservation and improvement of shrimp populations. The Pacific blue shrimp (Litopenaeus stylirostris) is a premium product in the international seafood market. However, intensified farming has increased disease incidence and reduced genetic diversity. In this study, we developed a transcriptome database for L. stylirostris and mined microsatellite markers to analyze their genetic diversity. Using the Illumina HiSeq 4000 platform, we identified 53,263 unigenes from muscle, hepatopancreas, the intestine, and lymphoid tissues. Microsatellite analysis identified 36,415 markers from 18,657 unigenes, predominantly dinucleotide repeats. Functional annotation highlighted key disease resistance pathways and enriched categories. The screening and PCR testing of 42 transcriptome-based and 58 literature-based markers identified 40 with successful amplification. The genotyping of 200 broodstock samples revealed that Na, Ho, He, PIC, and FIS values were 3, 0.54 ± 0.05, 0.43 ± 0.09, 0.41 ± 0.22, and 0.17 ± 0.27, respectively, indicating moderate genetic variability and significant inbreeding. Four universal microsatellite markers (CL1472.Contig13, CL517.Contig2, Unigene5692, and Unigene7147) were identified for precise diversity analysis in Pacific blue, Pacific white (Litopenaeus vannamei), and black tiger shrimps (Penaeus monodon). The transcriptome database supports the development of markers and functional gene analysis for selective breeding programs. Our findings underscore the need for an appropriate genetic management system to mitigate inbreeding depression, reduce disease susceptibility, and preserve genetic diversity in farmed shrimp populations. [ABSTRACT FROM AUTHOR]

IntroductionThe present study aimed to evaluate the effects of substituting fish meal with pork meal in feed on the growth performance, feed utilization, intestinal morphology, and immune function of Penaeus monodon.MethodsA total of 600 uniformly sized juvenile shrimp with an initial weight of 1.20 ± 0.03 g were randomly assigned to four groups, with each group consisting of six replicates of 25 shrimp each. Fish meal protein was replaced with 0%, 5%, 10%, and 15% pork meal, and crystalline amino acids and fish oil were supplemented accordingly. The groups were designated as P0, P5, P10, and P15, and the study duration was 70 days.ResultsResults indicated no significant difference in specific growth rate (SGR) between the P5 and P10 groups compared to the P0 group. However, the SGR in the P15 group was significantly lower than that in the P5 and P10 groups. Feed conversion rates (FCRs) for the P5 and P10 groups were comparable to the P0 group, whereas the P15 group showed a significantly higher FCR than the other groups. There were no significant differences in whole body composition among all the groups. Apart from alanine, the amino acid composition of muscles did not differ significantly among all the groups. Results of enzyme activity in plasma revealed that the replacement of fish meal with pork meal reduced levels of aspartate aminotransferase (AST) and superoxide dismutase (SOD). Specifically, levels of AST in the P5 and P15 groups were significantly lower compared to the P0 and P10 groups. Histological examination of midgut tissues showed that villus height initially increased and then decreased with higher replacement ratios. The P5 group had the highest villus height, while the P15 group had the lowest villus height. Analysis of gene expression related to liver immune functions indicated that genes in TLR signaling pathway were significantly elevated in the P15 group compared to the other groups.DiscussionIn conclusion, even with the supplementation of crystalline amino acids and fish oil, pork meal should not replace more than 10% of fish meal in the feed of P. monodon to maintain optimal growth and feed efficiency.

The invasive black tiger shrimp has caused serious ecological problems in the America. However, since it can be directly eaten or made into feed, it may be beneficial to other countries. In order to ensure ecological security, it is necessary to control the invasion of the black tiger shrimp through international cooperation. Common control modes of the black tiger shrimp include the introducing natural enemy mode, making feed mode and the "bringing to the table" mode. In order to derive the applicable scope of various control modes of the black tiger shrimp and provide suggestions for the security and sustainability of the ecological supply chain of the America and cooperative country, this article constructs three differential game models and compares and analyzes the equilibrium results obtained by the models. Finally, the study shows that the higher the price of feed and the price of black tiger shrimp, the greater the degree of control of the black tiger shrimp. If the price of the black tiger shrimp and the reputation of the America for controlling the black tiger shrimp are lower, the America can gain more benefits under the feed production mode. Otherwise, the America prefers to sell the black tiger shrimp directly, thus directly "bringing to the table". Compared with the feed production or "bringing to the table" mode, cooperative country prefer to control the black tiger shrimp flooding through the natural enemy introduction mode. [ABSTRACT FROM AUTHOR]

Salinity is a common abiotic stress in the culture of penaeid shrimp. Through posttranscriptional regulation of gene transcripts, microRNAs (miRNAs) play an important role in theadaptation toastressfulenvironment. However, theinvolvementofmiRNAs in the salinity stress response of shrimp remains unclear. In the present study, the sequence and expression profile of miRNAs in the hepatopancreas of low-salinitytreated Penaeus monodon were obtained by the high-throughput sequencing technique. A total of 679 miRNAs were identified, including 167 miRNAs that were significantly differentially expressed after low-salinity exposure (p <0.05). Remarkably, most of these miRNAs were downregulated, suggesting that a series of genes were activated to participate in stress response. In addition, 43 miRNAs differentially expressed at all treatment were selected as putative key modulators. Enrichment analysis of genes targeted by these miRNAs indicated that a network that consists of the nervous system, the immune system, and the endocrine system played a crucial role in maintaining the homeostasis of P. monodon under low-salinity stress. These findings may help contribute to a better understanding of the mechanism that regulates salinity tolerance in shrimp and provide valuable genetic information for subsequent studies. [ABSTRACT FROM AUTHOR]

Fermented rice bran (FRB) was evaluated as an alternative protein source to soybean meal (SM) in practical diets for juvenile black tiger shrimp, Penaeus monodon. This feed ingredient was tested in a feeding trial to replace soybean meal in P. monodon diets at 0% (T0), 12.5% (T12.5), 25% (T25), 37.5% (T37.5), and 50% (T50). Five iso-nitrogenous and iso-caloric experimental diets containing 44% crude protein were fed to groups of juvenile shrimp (0.47 ± 0.002 g) randomly assigned to twenty 60-l rectangular tanks equipped with a recirculating seawater system. Each dietary treatment was run in 4 replicates, and the feeding trial lasted 50 days. Results show significant improvement in weight gain, specific growth rate, and protein efficiency ratio in treatment T12.5 and T25. Treatments with higher levels of SM replacement with FRB exhibited similar growth indices to those of the control group. Polynomial regression analysis indicates that the optimum replacement of soybean meal with FRB for optimum growth is 21.08%. The apparent dry matter and protein digestibility coefficients of FRB are 83.05 ± 0.02% and 87.20 ± 0.30%, respectively. There were no significant differences in the whole-body composition (dry matter, protein, lipid, ash) among treatments of shrimp fed with FRB replacement. The data suggest that FRB replacement of dietary soybean meal is feasible at 50% without affecting the growth performance but may promote growth at 21.08% replacement of P. monodon. [ABSTRACT FROM AUTHOR]

Due to the widespread use of shellfish ingredients in food products, accurate food labelling is urgently needed for consumers with shellfish allergies. Most crustacean allergen detection systems target the immunorecognition of the allergenic protein tropomyosin. However, this mode of detection may be affected by an origin-dependent protein composition. This study determined if the geographic location of capture, or aquaculture, influenced the allergenic protein profiles of Black Tiger Shrimp (Penaeus monodon), one of the most farmed and consumed shrimp species worldwide. Protein composition was analysed in shrimp from nine different locations in the Asia–Pacific by SDS-PAGE, immunoblotting, and mass spectrometry. Ten of the twelve known shrimp allergens were detected, but with considerable differences between locations. Sarcoplasmic calcium-binding protein, myosin light chain, and tropomyosin were the most abundant allergens in all locations. Hemocyanin-specific antibodies could identify up to six different isoforms, depending on the location of origin. Similarly, tropomyosin abundance varied by up to 13 times between locations. These findings suggest that allergen abundance may be related to shrimp origin and, thus, shrimp origin might directly impact the readout of commercial crustacean allergen detection kits, most of which target tropomyosin, and this should be considered in food safety assessments. [ABSTRACT FROM AUTHOR]

In order to study the muscle quality of different crustaceans, we aim to provide a comprehensive assessment of their muscle quality characteristics as a theoretical reference. In this work, seven major species of farmed and consumer crustaceans were selected, including crayfish (Procambarus clarkii), freshwater prawns (Macrobrachium rosenbergii), pacific white shrimp (Litopenaeus vannamei), black tiger shrimp (Penaeus monodon), kuruma prawns (Penaeus japonicus), river prawns (Macrobranchium nipponense), and Chinese shrimp (Penaeus chinensis). Their morphometric parameters, nutritional composition, textural properties, and physical and chemical indexes were comparatively analyzed. The results showed that the meat content (MC, about 14.78%) of crayfish was significantly lower than that of the other six species. By contrast, pacific white shrimp had the highest MC, although the MCs of black tiger shrimp, kuruma prawns, and Chinese shrimp are greater than 40%. All seven crustacean species were high in protein and low in fat, while pacific white shrimp had the highest crude protein, crude lipid, and crude ash content compared to the other crustaceans. The content of threonine (Thr) was the highest in crayfish. The content of methionine (Met) and lysine (Lys) was the highest in freshwater prawns. The content of isoleucine (Ile), leucine (Leu), and non–essential amino acid (NEAA) was the highest in pacific white shrimp. C18:2n-6 (linoleic acid, LA) was the highest in freshwater prawns and pacific white shrimp; C18:3n-3 (linolenic acid, LNA), C20:4n-6 (arachidonic acid, AA), unsaturated fatty acids (UFA), and monounsaturated fatty acids (MUFA) were all the highest in crayfish; and polyunsaturated fatty acids (PUFA) was the highest in freshwater prawns, but the content was not significantly different from crayfish, pacific white shrimp, black tiger shrimp, and Chinese shrimp. Pacific white shrimp had the highest values for hardness, cohesiveness, gumminess, and chewiness. The redness values of crayfish, black tiger shrimp, and Chinese shrimp were significantly higher than those of the other three species except kuruma prawns. Compared to other crustaceans, river prawns had the highest drip loss and cooking loss. Black tiger shrimp and Chinese shrimp had the lowest cooking loss rates. The research shows that the tail muscle of the seven species of crustaceans is rich in protein, essential amino acids, unsaturated fatty acids and low in fat, representing a high-quality protein. Among these crustaceans, the main essential amino acids and essential fatty acids in the tail muscle of pacific white shrimp, freshwater prawns, and crayfish are higher in content and better in nutritional value. [ABSTRACT FROM AUTHOR]

Simple Summary: Seaweeds and probiotics are commonly utilized as additives in the diet of aquatic animals. However, limited information exists regarding the effects of Gracilaria lichenoides and Bacillus amyloliquefaciens, either alone or in combination, on Penaeus monodon. In our study, we examined the impact of dietary supplementation with G. lichenoides and B. amyloliquefaciens, both individually and in combination, on the growth performance, antioxidant capacity, and intestinal function of P. monodon. Our findings indicate a beneficial influence of dietary G. lichenoides and B. amyloliquefaciens on P. monodon. These findings offer a theoretical foundation for the judicious utilization of G. lichenoides and B. amyloliquefaciens in the cultivation of black tiger shrimp, as well as for future investigations into their metabolic mechanisms. This research sought to assess the effects of dietary supplements with Gracilaria lichenoides and Bacillus amyloliquefaciens, either individually or combined, on the growth performance, antioxidant capacity, and intestinal function of Penaeus monodon. A total of 840 shrimps were randomly assigned to 28 tanks with an average initial weight of (1.04 ± 0.03) g (30 shrimp per tank) with 7 different treatment groups and 4 replicates per treatment. The control treatment (C) consisted of a basal diet; in contrast, the experimental groups were complement with varying levels of G. lichenoides (3% or 8%), either alone (S3 and S8) or in combination with B.amyloliquefaciens at different concentrations (3% G. lichenoides and 109 CFU/g—S3B9; 8% G. lichenoides and 1011 CFU/g B. amyloliquefaciens—S8B11; 109 CFU/g B. amyloliquefaciens—S9; 1011 CFU/g B. amyloliquefaciens—B11). The results indicated that the maximum values of final body weight (FBW) (10.49 ± 0.90) g, weight gain rate (WGR) (908.94 ± 33.58) g, and specific growth rate (SGR) (4.20 ± 0.06) g were perceived in the 3% G. lichenoide diet treatment, and compared with the control group, the difference was significant (p < 0.05). The whole-body lipid content of shrimp in the B9 group was significantly higher than that in the B11 group (p < 0.05), but no significant difference was observed when compared with shrimp fed other diets (p > 0.05). The ash content of shrimp in the B9 group was found to be significantly higher than that in the S3B9 group (p < 0.05). Furthermore, the lipase activity in the stomach and intestines of the experimental groups exhibited a statistically significantly increase compared to the control (p < 0.05). In comparison to the control group, the hepatopancreas of the S3 group exhibited a significant increase in the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and antioxidant genes [SOD, catalase (CAT), GSH-Px, thioredoxin (Trx), Hippo, and NF-E2-related factor 2 (Nrf2)] expression levels (p < 0.05). Additionally, the activities of total antioxidant capacity (T-AOC), SOD, peroxidase (POD), and antioxidant genes (CAT, GSH-Px, Trx, and Hippo) in the S3B9 treatment of hepatopancreas showed significant improvement (p < 0.05). The inclusion of dietary G. lichenoides and B. amyloliquefaciens resulted in enhanced relative expression of intestinal lipid metabolism genes (fatty acid synthetase (FAS), lipophorin receptor (LR), fatty acid transport protein 1 (FATP1)) and suppressed the expression of the long-chain fatty acid-CoA ligase 4 (LCL4) gene. Analysis of microbiota sequencing indicated improvements in composition and structure, with notable increases in Firmicutes at the phylum level and Vibrio at the genus level in the S3 group, as well as an increase in Tenericutes at the genus level in the S8B11 group. Overall, the inclusion of dietary G. lichenoides and B. amyloliquefaciens positively impacted the growth, antioxidant capacity, and microbial composition of shrimp, with particular enhancement observed in shrimp fed a supplementary 3% G. lichenoides diet. [ABSTRACT FROM AUTHOR]

Aquaculture recirculation technology has evolved in recent years, as it can save water use and maintain good water quality during tiger shrimp fry rearing and ultimately increase juvenile production. The recirculation technology in this experiment is expected to be adopted by small‐scale tiger shrimp seed farmers. This study aims to develop the technology for producing a juvenile tiger shrimp recirculation system to support shrimp cultivation in ponds. The recirculation system container comprises a biofiltration tank filled with oysters, seaweed, and tilapia. Containers to keep tiger shrimp larvae alive in the recirculation system use a round‐shaped container with a volume of 2 m3. Tiger shrimp larvae were cared for at; A. density of 2000 individuals/m2; B. density of 1500 individuals/m2; and C. density of 1000 individuals/m2. This study found that the survival rate of tiger shrimp in treatments C and B were high, reaching 96.800b ± 2.716% and 91.62b ± 3.432%, respectively, while survival in treatment A was the lowest, at 81.700a ± 4.715%. [ABSTRACT FROM AUTHOR]

Wet markets in low-and middle-income countries are often reported to have inadequate sanitation resulting in fecal contamination of sold produce. Consumption of contaminated wet market-sourced foods has been linked to individual illness and disease outbreaks. This pilot study, conducted in two major wet markets in Dhaka city, Bangladesh during a 4-month period in 2021 aimed to assess the occurrence and characteristics of Escherichia coli and nontyphoidal Salmonella spp. (NTS) from tilapia (Oreochromis niloticus) and shrimp (Penaeus monodon). Fifty-four individuals of each species were collected. The identity of the bacterial isolates was confirmed by PCR and their susceptibility toward 15 antimicrobials was tested by disk diffusion. The whole genome of 15 E. coli and nine Salmonella spp. were sequenced using Oxford Nanopore Technology. E. coli was present in 60–74% of tilapia muscle tissue and 41– 44% of shrimp muscle tissue. Salmonella spp. was found in skin (29%) and gills (26%) of tilapia, and occasionally in muscle and intestinal samples of shrimp. The E. coli had several Multilocus sequence typing and serotypes and limited antimicrobial resistance (AMR) determinants, such as point mutations on glpT and pmrB. One E. coli (BD17) from tilapia carried resistance genes for betalactams, quinolones, and tetracycline. All the E. coli belonged to commensal phylogroups B1 and A and showed no Shiga-toxin and other virulence genes, confirming their commensal non-pathogenic status. Among the Salmonella isolates, five belonged to Kentucky serovar and had similar AMR genes and phenotypic resistance patterns. Three strains of this serovar were ST198, often associated with human disease, carried the same resistance genes, and were genetically related to strains from the region. The two undetermined sequence types of S. Kentucky were distantly related and positioned in a separate phylogenetic clade. Two Brunei serovar isolates, one Augustenborg isolate, and one Hartford isolate showed different resistance profiles. This study revealed high fecal contamination levels in tilapia and shrimp sold at two main wet markets in Dhaka. Together with the occurrence of Salmonella spp., including S. Kentucky ST198, a well-known human pathogen, these results stress the need to improve hygienic practices and sanitation standards at markets to improve food safety and protect consumer health. [ABSTRACT FROM AUTHOR]

Mohale, H.P.; Jawahar, P.; Jayakumar, N.; Oli, G. Arul; Ravikumar, T., and Bhosle, R., 2024. Ecomorphology of selected penaeid shrimp in the coastal marine waters of Tamil Nadu (southern India). Journal of Coastal Research, 40(2), 303–318. Charlotte (North Carolina), ISSN 0749-0208. This study investigated how shrimp morphology is influenced by the environment by examining the effects of components like temperature, salinity, substrate type, and water currents; it exposed how these variables affect the development and expression of morphological traits in shrimp species by examining patterns of morphological variation within and between species to demonstrate the contributions of natural selection, genetic drift, and phenotypic plasticity to the diversification of shrimp morphology. The prevalence of shrimp species was: Penaeus indicus > Metapenaeus dobsoni > Metapenaeus brevicornis > Penaeus canaliculatus > Penaeus semisulcatus > Penaeus mergiuensis > Penaeus japonicas > Metapenaeus moyebi > Penaeus latisulcatus > Penaeus monodon. The study results showed negative correlations between biochemical oxygen demand and dissolved oxygen and a harmful effect on the morphological characteristics and growth of shrimp species. According to single factor and comprehensive pollution indices, the water bodies in this study were moderately polluted. P. semisulcatus had higher mean values for the ecomorphology parameters, indicating no adverse effects and a positive relationship. P. semisulcatus shrimp were also found to have decadal growth development and survivability. P. mergiuensis had the lowest growth rates. Results indicated detrimental effects and a bad association when evaluating decadal growth, development, and survival for most of the other shrimp species. This study enhances knowledge of the evolutionary processes that have shaped shrimp adaptations over time and highlights the challenges for sustainability of the biodiversity in the coastal marine waters of Tamil Nadu, India. [ABSTRACT FROM AUTHOR]

The effects of three feed additives in a low fish meal diet on growth, antioxidant capacity and intestinal microbiota of Penaeus monodon were studied to enhance the understanding of these effects and to provide basic data and a reference for the formulation and optimization of feed for P. monodon. A total of 630 healthy, homogenous shrimp (4.58 ± 0.05 g) were randomly divided into seven groups with three replicates per group and 30 shrimp per replicate in a breeding barrel (500 L). The additive names and amounts were 0 (CT); vitamin B6, 100 mg/kg (V1); vitamin B6, 200 mg/kg (V2); phytase, 1000 U/kg (P1); phytase, 2000 U/kg (P2); 0.2% yucca extract (Y1); and 0.4% yucca extract (Y2). The experiment lasted 8 weeks. The results showed that compared to CT, V1 and Y1 had a significant increasing tendency toward weight gain (WG) (p < 0.05) and had a significant decreasing tendency in the food conversion ratio (FCR) (p < 0.05). P2 had a significant increasing tendency in α-amylase activity (p < 0.05), and P1 had a significant increasing tendency in total superoxide dismutase (T-SOD) (p < 0.05). The next-generation sequencing of intestinal microbiota showed that Proteobacteria was the most abundant phylum in the seven groups, accounting for 29.33%, 56.67%, 55%, 45.33%, 73%, 39.33% and 64.33% of the total. Compared to CT, the Proteobacteria was significantly high (p < 0.05) in P2 and Y2, and the Bacteroidota in all other groups decreased significantly (p < 0.05). The functional prediction of FAPROTAX indicated that there was no significant difference (p > 0.05) in functional components among all groups. According to growth performance, antioxidant capacity and effects on intestinal microbiota, vitamin B6 (100 mg/kg), phytase (2000 U/kg) and yucca extract (0.2%) can be recommended as additives for the diet of P. monodon. [ABSTRACT FROM AUTHOR]

Internally or self-doped oxygen–nitrogen–phosphorus heteroatoms are useful in increasing the hydrophilicity, wettability, and conductivity of supercapacitor cell electrodes. These properties are positively related to electrochemical supercapacitive behavior. Therefore, this study aimed to examine activated green resources from black tiger shrimp shells (BTS) to produce O-N-P self-co-doped carbon (C) nanofibers for a high-performance supercapacitor. KOH was used to determine the content of heteroatoms in the carbon matrix. The results showed that the composition of BTS contained 10.01 wt% nitrogen, 40.92 wt% carbon, 23.16 wt% oxygen, and 4.92 wt% phosphorus, confirming the presence of O-N-P self-doping. Furthermore, the carbon matrix exhibited a nanofiber structure with the presence of nanopores (micro-mesopore co-extension), which showed the highest specific capacitance of 315 F/g at 1 mV/s in 1 M H2SO4 solution. BTS supercapacitor cells designed on a symmetrical electrode system achieved a specific power of 323 W/Kg at a specific energy of 9.59 Wh/Kg. These results indicated that internal heteroatoms doping was a strategy for improving the electrochemical performance of environmentally friendly, efficient, economical, and sustainable supercapacitor cells. [ABSTRACT FROM AUTHOR]

White spot disease (WSD) occurred by the highly devastating white spot syndrome virus (WSSV) poses a serious impediment toward global shrimp production. We investigated molecular diagnosis and natural infection with WSSV in cultured tiger shrimp (Penaeus monodon) and inspected histopathology of WSD. The incidence of WSSV infection was recorded in six small-scale shrimp farms situated in two districts of Bangladesh, namely Bagerhat and Satkhira. One- and two-step nested polymerase chain reaction models were applied to check the presence of WSSV DNA in shrimp samples. By one-step PCR, 25 of the 36 shrimp samples were WSSV-positive, while the remaining 11 samples were found to be WSSV-negative. After the negative samples underwent a two-step PCR process, only three samples were detected WSSV negative. In Satkhira and Bagerhat districts, the prevalence rates of WSSV infection were 83.33% and 55.56%, respectively, as confirmed by one-step PCR; following two-step nested PCR, the prevalence rates remained unchanged for Satkhira but increased to 100% for Bagerhat sourced samples. One-step PCR was less effective than two-step nested PCR in diagnosing viral infection; instantly evident that the overall prevalence rate rose from 69.44% to 91.67% when switching to two-step nested PCR. In a different experiment, histological analyses of PCR-confirmed WSSV-positive shrimp specimens revealed degenerated tubule lumen and degenerated hepatopancreas with necrosis, while the infected muscle tissues showed muscle fiber fragmentation and separation. Based on effective PCR technique and histopathological evidence of WSSV infection, the study demonstrated the occurrence of WSSV infection in small-scale shrimp farms. The combined practices of the diagnostic tools and information will be useful in understanding the white spot disease and managing its prevention in shrimp production systems.

Exposure to air pollution has been identified as a significant contributor to illness and premature death worldwide. Neurotoxic pollutants can harm the developing brains of fetuses, infants, and children, leading to cognitive impairments and behavioral disorders. There is also evidence linking air pollution to neurodegenerative diseases in adults, such as Alzheimer's disease. The Special Issue discussed in the article focuses on the effects of environmental pollutants on human health, particularly at a neurological level. It includes studies on the role of exosomes in cerebrovascular impairment, the impact of solid nanoparticles on brain development, the effects of photodynamic antimicrobial chemotherapy on crustaceans, and the neurotoxicity of polycyclic aromatic hydrocarbons. These studies provide insights into the mechanisms and risks associated with exposure to environmental pollutants. [Extracted from the article]

Chitin deacetylase (CDA) can catalyze the deacetylation of chitin to produce chitosan. In this study, we identified and characterized a chitin deacetylase gene from Euphausia superba (EsCDA-9k), and a soluble recombinant protein chitin deacetylase from Euphausia superba of molecular weight 45 kDa was cloned, expressed, and purified. The full-length cDNA sequence of EsCDA-9k was 1068 bp long and encoded 355 amino acid residues that contained the typical domain structure of carbohydrate esterase family 4. The predicted three-dimensional structure of EsCDA-9k showed a 67.32% homology with Penaeus monodon. Recombinant chitin deacetylase had the highest activity at 40 °C and pH 8.0 in Tris-HCl buffer. The enzyme activity was enhanced by metal ions Co2+, Fe3+, Ca2+, and Na+, while it was inhibited by Zn2+, Ba2+, Mg2+, and EDTA. Molecular simulation of EsCDA-9k was conducted based on sequence alignment and homology modeling. The EsCDA-9k F18G mutant showed a 1.6-fold higher activity than the wild-type enzyme. In summary, this is the first report of the cloning and heterologous expression of the chitin deacetylase gene in Euphausia superba. The characterization and function study of EsCDA-9k will serve as an important reference point for future application. [ABSTRACT FROM AUTHOR]

The bioremediation efficiency of the sea cucumber, Holothuria scabra, held at different stocking densities as an eco-based waste treatment technology on the quality of water and sediment of the Penaeus monodon pond culture, was evaluated in this study. Two separate experiments were simultaneously conducted indoors for five days using 100-L capacity aquaria. The treatments for the pond water experiment were: (T1) control, 10 L pond water only, (T2) 10 L pond water + one sea cucumber, and (T3) 10 L pond water + two sea cucumbers. For the pond sediment experiment, the conditions of the three treatments were the same except that pond sediments were added in each aquarium. The results showed that T2 had a significant reduction of ammonia (28%), and nitrite (84%) in pond water, and nitrogen (88%) and phosphorus (9%) in pond sediment. It also efficiently improved the management of the microbial load with a significant decrease, particularly in heterotrophs (39%) in pond water compared to that in the control treatment. The results showed that the presence and activity of H. scabra have a positive bioremediation effect on waste as demonstrated by reduced ammonia, nitrite, nitrogen, and phosphorus levels and microbial load from the P. monodon pond water and sediment. Furthermore, the stocking density of one sea cucumber is more efficient in reducing these wastes compared to the two sea cucumbers stocking density. The result suggested that H. scabra can be a potentially efficient bioremediator of waste in shrimp ponds. [ABSTRACT FROM AUTHOR]

The current study profiled the dual isotopes of carbon and nitrogen in feeds and muscles of farmed Penaeus monodon for evaluation of feed efficiency in making up the prawn muscle. Signatures of both feed and resulted muscles of P. monodon were subjected to two‐ and three‐source linear mixing models to elucidate the contribution of each feed item in the building of the muscle. The results revealed that carbon and nitrogen in different feed substances have different influences on the growth and nutrient uptake by the prawn. Different growth stages showed isotopic switching within prawn muscles in the course of their building up. Generally, marine sources were the most enriched in both δ13C and δ15N. Likewise, δ13C of wild‐caught prawns (−16.30 ± 0.72‰) were superior over farmed prawns (−18.00 ± 0.59‰) (p < 0.01), whereas no significant differences were observed in δ15N values between wild (8.03 ± 0.65‰) and farmed (8.38 ± 1.39‰) (p > 0.01). The isotopic composition of P. monodon mirrored those of the ingredients contained in its feed and varied across treatment levels. Comparing to other ingredients, marine macroalgae exhibited significantly higher (p < 0.01) feed efficiency, and as a result, they improved the growth of P. monodon compared to the other ingredients. The same treatment recorded significantly lower (p < 0.01) feed conversion ratio compared to other treatments. However, muscle somatic index, specific growth rate and condition factor were not significantly different across treatments (p > 0.01). Moreover, a clear distinction was observed between wild and farmed P. monodon, and such a distinction is clearly explained by δ13C composition. In conclusion, multiple sources of δ13C and δ15N in feeds are incorporated more efficiently in muscles than single sources.Stable isotope bi‐plot showing mean values of wild (PW) and cultured prawns (PC); the red arrow shows stable isotope enrichment and depletion directions. [ABSTRACT FROM AUTHOR]

In this study, Penaeus monodon were gave basic feed supplemented with three levels of Enterococcus faecium. Then, the expression of non-specific immunity-related genes, and the activities of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), malondialdehyde (MDA), acid phosphatase (ACP), alkaline phosphatase (AKP), phenol oxidase (PO) were evaluated. Meanwhile, the disease resistance test and intestinal flora determination were conducted. The results showed that the MDA levels of 2% and 5% E. faecium groups were significantly lower than that of the control group (P < 0.05). While the SOD and T-AOC and ACP and AKP of experimental groups were significantly higher (P < 0.05), the PO of experimental groups were significantly lower than that of the control group (P < 0.05). In addition, the expressions of immunity-related genes (tlr22, dorsal, lysozyme, crustin, imd, and relish) in the 2% and 5% E. faecalis groups were significantly greater than those in the control group (P < 0.05). After P. monodon was challenged with Vibrio parahaemolyticus for 7 days, the average cumulative mortality of P. monodon in the 2% and 5% groups were significantly lower than that in the 0% group (P < 0.05). With the increase of feeding time, the number of effective OTUs in each group showed a downward trend. At the 14th d, Proteobacteria, Bacteroidetes and Firmicutes, the dominant flora in the intestinal tract of P. monodon. In summary, supplied with E. faecium could increase the expression of non-specific immunity-related genes, enhance the immune capacity of P. monodon. [ABSTRACT FROM AUTHOR]

China’s shrimp farming industry has experienced significant growth in recent years. With such a development, some major constraints linked to the industry’s sustainable development have emerged. This paper aims to present an overview of China’s shrimp industry over the last two decades, with special attention to farm-raised shrimp both in marine and inland waters. Documentary research on its recent evolution was carried out based on data collected from China Fishery Statistics Yearbooks 2003 to 2022 coupled with data from FAO. Findings indicated that there has been an upward trend in China’s total shrimp production over the last 20 years, with a growth rate of 120%, representing an average annual growth rate of 4.3%. The observed higher shrimp production was driven by expanded shrimp aquaculture production, with major species dominated by the Pacific whiteleg shrimp (litopenaeus vannamei), the black tiger shrimp (Penaeus monodon), the Chinese shrimp (Penaeus chinensis), and the Japanese prawn (Penaeus japonicus). Challenges associated with the intensification of the production and the driven environmental deterioration need to be properly addressed. First, the shrimp farming industry should be practiced while considering both environment and ecosystem protection. Applying such an organic farming principle presupposes some practices for addressing the existing issues threatening the sustainable growth of the industry. To that end, there is a need for innovative techniques that should be strengthened. Second, possible solutions to shrimp disease problems, namely prevention, early diagnosis, and various control techniques, should also be developed and improved, with an emphasis on the former. In addition, encouraging the use of good-quality feed in appropriate quantity and form is also of paramount importance. It is thus worth noting that further policies need to focus on promoting a large range of ecological shrimp aquaculture technologies that should be encouraged among farmers. [ABSTRACT FROM AUTHOR]

The aim of this experiment was to investigate the effects of the partial substitution of fish meal with soybean products and chicken meal on the growth performance, antioxidant capacity and intestinal microbiota of Penaeus monodon. A total of 450 healthy, consistent shrimp were randomly divided into five groups, with three replicates per group and 30 shrimp per replicate. The proportion of fish meal substituted with soybean products and chicken meal in the five feed groups was 0% (FM), 40% (40SC), 60% (60SC), 80% (80SC) and 100% (100SC). The experiment lasted for 8 weeks. The results showed that, compared to the FM group, the 40SC and 60SC groups had a decrease in WG and SR, but there was no significant difference (p > 0.05). In contrast, compared to the FM group, the FCR in the 100SC group was significantly increased (p < 0.05), while there was no significant difference among the FM and 40SC, 60SC and 80SC groups (p > 0.05). Compared to the FM group, the ACP in the 80SC and 100SC groups significantly increased (p < 0.05), while the 40SC and 60SC groups had no significant difference (p > 0.05). The AKP in the 100SC group was significantly higher than that in the FM group (p < 0.05), while there were no significant differences among the other four groups (p > 0.05). There were no significant differences in T-AOC and T-SOD among all the treatment groups (p > 0.05). The next-generation sequencing of the intestinal microbiota showed that Proteobacteria was the most abundant phylum in the five groups, accounting for 37.67%, 66%, 40%, 40% and 43.33%, respectively. Compared to the FM group, the Fusobacteriota in the other four groups decreased significantly (p < 0.05). The functional prediction of FAPROTAX indicated that no functional components were observed which are harmful to the body. Considering the effects on growth performance, antioxidant capacity and intestinal microbiota, it is feasible to use soybean products and chicken meal to replace 60% of fish meal in the feed of P. monodon. [ABSTRACT FROM AUTHOR]

Purpose: Although shrimp aquaculture in Sri Lanka has mainly been plagued by recurrent outbreaks of White Spot Syndrome Virus (WSSV), recent symptomatic and analytical field data of shrimps were incoherent with typical WSSV infections. As transboundary infection of new diseases is not uncommon in world shrimp aquaculture, the possibility of new diseases established in the country surfaced. Hence, the present study was aimed at evaluating the stock health of shrimps in Sri Lanka for additional six diseases commonly available in the Asian region, namely Infectious Hypodermal and Hematopoietic Necrosis Virus (IHHNV), Infectious Myonecrosis Virus (IMNV), Taura Syndrome Virus (TSV), Yellow Head Virus (YHV), Acute Hepatopancreatic Necrosis (AHPND) and Necrotizing Hepatopancreatitis Bacterium (NHPB). Research Method: Sampling was performed using broodstocks, postlarvae, cultured Penaeus monodon, wild P. semisulcatus, P. indicus and P. monodon from different locations and broodstock collecting areas in the country. Other crustacean species were also collected as possible carrier species. The presence of pathogenic organisms was identified by Polymerase Chain Reaction using respective IQ 2000TM test kits and a total of 2060 PCR tests were conducted. Findings: Of all the samples tested, no samples were positive for IMNV, TSV, YHV, AHPND and NHPB. However, confirmatory evidence was found in Sri Lanka for the presence of IHHNV with the prevalence of 31.3% in broodstock samples, 24.07% in hatchery-produced postlarvae and 18.03% in cultured shrimps. WSSV was also recorded with a prevalence of 10.34% in broodstock samples and 55.56% in cultured shrimp samples collected. None of the wild collected samples was positive for any of the tested diseases. Originality/value: Reinstating the presence of WSSV in the Sri Lankan shrimp industry, provides confirmatory evidence of the presence of IHHNV in the country, highlighting the possibility of the emergence of new diseases in shrimp farming in Sri Lanka. Also, commonly suggested disease carriers seem to be not the major cause of disease spread during the sampling time. This study, therefore, provides much-needed information about the stock health of shrimps in Sri Lanka. [ABSTRACT FROM AUTHOR]

Synthetic astaxanthin is an effective nutritional strategy for improving shrimp body color and promoting growth. However, the optimal amount of astaxanthin in feed also varies with the synthetic technology and purity. In the present study, five diets containing different doses of synthetic astaxanthin (0% (CON), 0.02% (AX0.02), 0.04% (AX0.04), 0.08% (AX0.08), and 0.16% (AX0.16)) were administered to Penaeus monodon (initial body weight: 0.3 ± 0.03 g) for 8 weeks. With an increase in astaxanthin content in feed, weight gain and specific growth rate increased initially and subsequently decreased, with the highest value appearing at AX0.08. Dietary astaxanthin supplementation obviously improved the carapace and muscle color by enhancing astaxanthin pigmentation. Meanwhile, the fatty acid profile was altered by dietary astaxanthin, as evidenced by a decline in palmitic acid proportion, along with an increase in n-3 polyunsaturated fatty acids (n-3 PUFA) contents in muscle. In addition, dietary astaxanthin supplementation regulated prawn's antioxidant capacity. In the hemolymph, the activities of glutamic pyruvic transaminase (GPT) showed a significantly decrease trend with linear effect. The activities of glutamic oxaloacetic transaminase (GOT) and the contents of malondialdehyde (MDA) were first downregulated and then upregulated with significantly quadratic pattern. In the hepatopancreas, the activities of superoxide dismutase (SOD) and the contents of MDA were significantly downregulated with the increase of dietary astaxanthin levels. Reduced glutathione (GSH) contents and catalase (CAT) activities were also significantly decreased in group AX0.08. Correspondingly, astaxanthin decreased GSH and MDA contents under transportation stress. Moreover, the mRNA expression of immune genes (traf6, relish, and myd88) were inhibited by dietary astaxanthin supplementation. Based on the results of polynomial contrasts analysis and Duncan's test, dietary synthetic astaxanthin is a suitable feed additive to improve the growth, body color, antioxidant capacity, and nonspecific immunity of P. monodon. According to the second-order polynomial regression analysis based on the weight gain, the optimal supplementation level of dietary astaxanthin was 90 mg kg−1 in P. monodon. [ABSTRACT FROM AUTHOR]

Bioluminescent bacteria (BLB) are the most widely distributed light-emitting microorganisms, most of which are found as symbionts of free-living marine organisms, including the crustacean species. In this study, 4 out of 7 marine crustaceans in the northeastern section of Manila Bay were found to contain bioluminescent bacteria. Marine crustacean species namely Thenus orientalis (Oriental Slipper Lobster), Oratosquilla oratoria (Mantis Shrimp), Penaeus monodon (Giant Tiger Prawn), Litopenaeus vannamei (Whiteleg shrimp), Scylla serrata (Mud Crab), Portunus pelagicus (Blue Swimming Crab), and Charybdis feriata (Crucifix crab), were swabbed after collection. Bioluminescent bacteria were isolated from the inner surface of the carapace, eyes, abdomen, and abdominal segments of the crustacean samples. All glowing colonies were isolated and upscaled. Only bioluminescent bacteria from T. orientalis, O. oratoria, and P. monodon completed the isolation process and were identified using 16S rRNA gene sequencing for phylogenetic analysis. Furthermore, results from molecular identification through Nucleotide BLAST identified that it was Vibrio alginolyticus and Mucus bacterium. At the same time, the presence of Vibrio rumoiensis was also identified which was proved to be understudied and needs exploration. This study was aimed to identify the present bioluminescent bacteria in selected marine crustaceans in Manila Bay, Philippines through microbiological isolation, molecular identification, and phylogenetic reconstruction. [ABSTRACT FROM AUTHOR]

Fermented rice bran (FRB) was evaluated as an alternative protein source to soybean meal (SM) in practical diets for juvenile black tiger shrimp, Penaeus monodon. This feed ingredient was tested in a feeding trial to replace soybean meal in P. monodon diets at 0% (T0), 12.5% (T12.5), 25% (T25), 37.5% (T37.5), and 50% (T50). Five iso-nitrogenous and iso-caloric experimental diets containing 44% crude protein were fed to groups of juvenile shrimp (0.47 ± 0.002 g) randomly assigned to twenty 60-l rectangular tanks equipped with a recirculating seawater system. Each dietary treatment was run in 4 replicates, and the feeding trial lasted 50 days. Results show significant improvement in weight gain, specific growth rate, and protein efficiency ratio in treatment T12.5 and T25. Treatments with higher levels of SM replacement with FRB exhibited similar growth indices to those of the control group. Polynomial regression analysis indicates that the optimum replacement of soybean meal with FRB for optimum growth is 21.08%. The apparent dry matter and protein digestibility coefficients of FRB are 83.05 ± 0.02% and 87.20 ± 0.30%, respectively. There were no significant differences in the whole-body composition (dry matter, protein, lipid, ash) among treatments of shrimp fed with FRB replacement. The data suggest that FRB replacement of dietary soybean meal is feasible at 50% without affecting the growth performance but may promote growth at 21.08% replacement of P. monodon.

Abstract The current study profiled the dual isotopes of carbon and nitrogen in feeds and muscles of farmed Penaeus monodon for evaluation of feed efficiency in making up the prawn muscle. Signatures of both feed and resulted muscles of P. monodon were subjected to two‐ and three‐source linear mixing models to elucidate the contribution of each feed item in the building of the muscle. The results revealed that carbon and nitrogen in different feed substances have different influences on the growth and nutrient uptake by the prawn. Different growth stages showed isotopic switching within prawn muscles in the course of their building up. Generally, marine sources were the most enriched in both δ13C and δ15N. Likewise, δ13C of wild‐caught prawns (−16.30 ± 0.72‰) were superior over farmed prawns (−18.00 ± 0.59‰) (p 0.01). The isotopic composition of P. monodon mirrored those of the ingredients contained in its feed and varied across treatment levels. Comparing to other ingredients, marine macroalgae exhibited significantly higher (p 0.01). Moreover, a clear distinction was observed between wild and farmed P. monodon, and such a distinction is clearly explained by δ13C composition. In conclusion, multiple sources of δ13C and δ15N in feeds are incorporated more efficiently in muscles than single sources.

Acute hepatopancreatic necrosis disease (AHPND) has inflicted massive economic losses and posed a considerable threat to the development of penaeid shrimp aquaculture in Malaysia. The restriction on antibiotic uses have necessitated exploring alternatives preventive measures against AHPND outbreak, such as the use beneficial bacteria and nutritional additives. In this study, diets which were fed to Penaeus monodon postlarvae (PL15) were fed with diets containing probiotic (L. plantarum at 108 CFU/mL), prebiotic (S. polycystum at 2%) and synbiotic diets (combination of probiotic and prebiotic) formulations. These diets were administered in triplicate for 35 days, followed by an immersion challenge with 6 × 105 CFU/mL AHPND-causing V. parahaemolyticus S2–4. Sampling of shrimp’s cephalothorax and abdomen from the feeding trial and the immersion challenge were conducted for gene expression and histopathology analyses. Results indicated that the synbiotic-fed group displayed the most significant weight gain, specific growth rate, and protein conversion ratio among the tested groups. In addition, shrimp cephalothorax from this group displayed a significant immune response, with expression of LGBP, peroxinectin, prophenoloxidase during post-feeding trial, and expression of prophenoloxidase, toll-like receptor, penaeidin, during post-challenge trial. Furthermore, the highest L. plantarum concentration in abdomen, lowest V. parahaemolyticus S2–4 concentration in cephalothorax and highest percent survival of shrimp during post-challenge were observed in this group. Therefore, this study highlighted the positive effect of synbiotic-supplemented diet on growth, immune response, and disease resistance of shrimp, offering a promising and sustainable solution to alleviate substantial production losses in shrimp farming.

Astaxanthin is an efficient nutrition strategy to relieve oxidative stress and enhance crustacean body color. Because of technological and economic benefits, synthetic astaxanthin is favored by the aquatic feed industry. However, whether synthetic astaxanthin can achieve the effects of natural astaxanthin needs further investigation. Here, we evaluated the effects of synthetic astaxanthin and natural astaxanthin (dietary supplementation with Haematococcus pluvialis and Phaffia rhodozyma) on the growth performance, body color, fatty acid composition and antioxidant capacity of black tiger prawn (Penaeus monodon). Compared with the control group (no astaxanthin supplementation), only synthetic astaxanthin significantly increased the weight gain rate (WG) and specific growth rate (SGR), together with the elevation of feed efficiency ratio (FER). All three types of astaxanthin enhanced body color by increasing astaxanthin deposition. The highest value of (a*) in the carapace and muscle occurred in the synthetic astaxanthin group. Synthetic astaxanthin significantly increased the n-3 polyunsaturated fatty acid (n-3 PUFA) contents in muscle. As expected, different sources of astaxanthin inhibited glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) activities in the hemolymph and decreased the contents of reduced glutathione (GSH) and malondialdehyde (MDA) in the hepatopancreas. Correspondingly, the structure of hepatopancreas was enhanced by astaxanthin. In addition, three types of astaxanthin almost indistinguishably enhanced the ability of shrimps to resist stress caused by transportation simulation. In conclusion, these results indicate that dietary synthetic astaxanthin has a better effect than natural astaxanthin on growth promotion, body color enhancement and n-3 PUFA deposition in muscle of black tiger prawn. Hence, synthetic astaxanthin is a suitable feed additive to promote the healthy and sustainable development of the shrimp industry.

Vibrio parahaemolyticus, the causative agent of Acute hepatopancreatic necrosis disease (AHPND), was discovered in 2013 as a unique isolate that produces toxins and kills penaeid shrimps in devasting nature in Bangladesh and causes severe economic losses. This research aimed to understand the expressions of immune genes in different stages of the host species, Penaeus monodon, against virulence and toxin genes upon being challenged with V. parahaemolyticus. Healthy post-larvae (PL) samples were collected from southwestern of Bangladesh from July 2021 to August 2022. The tryptic soy agar with 1.5% sodium chloride (NaCl) was used to inoculate the cells of V. parahaemolyticus, and the tryptic soy broth (TSB) with 1.5% NaCl was used to transfer the colonies. The spectrophotometry measured bacteria density. PCR, qPCR, SDS-PAGE, and Western blot measured gene expression and survivability after the immersion challenge. The 1 × 105CFU/mL of V. parahaemolyticus was used for 144 h.p.i (hours post-infection) challenge to six stages of post-larvae (PL) of P. monodon (PL20, PL25, PL30, PL35, PL40, and PL45), PL30 and PL35 showed 100% mortality by day 72 (h.p.i.) after exposure that indicated most vulnerable to V. parahaemolyticus. The expression of immune and toxic genes was confirmed by qPCR. The immune genes toll-like receptors (TLR), prophenoloxidase (ProPO), lysozyme (lyso), and penaeidin (PEN) of PL20 and PL25 of P. monodon were expressed robustly up-trends. PL30 and PL35 showed the lowest gene expression at the end of 72 (h.p.i.). At the end of the 144 (h.p.i.) exposure, the immune genes TLR, ProPO, lyso, and PEN expressed highest in PL45 than other post-larvae stages of P. monodon. The toxic genes (pirA, ToxR, ToxA, ToxB, tlh, tdh, and trh) in PL30 and PL35 of P. monodon after exposure of V. parahaemolyticus were expressed highest at the end of the 72 (h.p.i.). The lowest toxic genes expressions were revealed in PL20 and PL45 at the end of the 144 (h.p.i.). The SDS-PAGE analysis of proteins from the bacterium revealed identical protein profiles with toxic genes, and those toxins were further confirmed by Western blot. The 20 kDa, 78 kDa (ToxR), 20 kDa, 25 kDa (ToxA), 25 kDa (ToxB), 20 kDa, 27 kDa, 75 kDa (tdh), and 20 kDa, 27 kDa, 75 kDa, and 78 kDa (trh) proteins were strong responses in Western blot, indicating the crucial involvement of these immune-related genes in the defense and recovery of the first-line defense mechanisms during V. parahaemolyticus infection to shrimp. The all-toxic genes showed a unique homology and those derived from the common ancestor compared with V. parahaemolyticus (NCBI accession no. AP014859.1). All clades were derived with different traits with very low genetic distance, where the overall mean distance was 3.18 and showed a very uniform and homogenous pattern among the lineages. The V. parahaemolyticus infection process in different PL stages in P. monodon revealed novel insights into the immune responses. The responses may lead to the subsequent production of a DNA vaccine, enhancing shrimp health management to minimize the economic losses due to AHPND experiencing an outbreak of early mortality syndrome (EMS) toward sustainable production P. monodon (shrimp).

Nowadays, bacterial diseases caused by Vibrio spp. pose a significant obstacle to aquaculture growth, affecting socioeconomic development. The presence of pathogenic Vibrio spp. are gaining attention due to widespread mortality in fish and shellfish worldwide. This study investigates the distribution of virulence genes and their pathogenicity by experimentally infecting a healthy group of cultured shrimp, specifically Penaeus monodon. A total of 225 Vibrio spp. isolated from 210 cultured shrimp from various geographical regions in Peninsular Malaysia were examined, resulting in 13 Vibrio spp. being identified and characterized. According to virulence gene assessment, only eight of the 11 virulence genes were detected in the isolates, including chiA (89%), flaC (74%), tlh (72%), toxR (70%), luxR (40%), pirA (11%), pirB (11%), and hlyA (0.4%). Other virulence genes, such as tdh, trh, and ctxA, were not found in any of the isolates (0%). Then, three Vibrio isolates, including V. parahaemolyticus S12-3, V. campbellii S10-4, and V. rotiferianus S24-4, were selected for pathogenicity test based on highest number of virulence genes in each species. These species were subjected to immersion challenge test against postlarvae (PL) P. monodon approximately PL-20 with three different concentrations of 1 × 106, 1 × 107, and 1 × 108 CFU/mL. The V. parahaemolyticus S12-3 was determined to have lethal concentration 50 (LC50) 1 × 105 CFU/mL after 168 hr of exposure. The immersion challenge test resulted in a pale hepatopancreas and empty guts in P. monodon. Histopathological examination showed sloughing of epithelial cells in the hepatopancreatic tubule, hemocytic infiltration, massive vacuolation, and loss of hepatopancreatic tubule structure. Overall, the study demonstrated the virulence and pathogenicity of V. parahaemolyticus S12-3 toward P. monodon, which could be associated with its virulence properties. Furthermore, the current findings will be useful in developing microbiological risk assessments for shrimp farming and aquaculture management. [ABSTRACT FROM AUTHOR]

This study aims to reduce the cost of allergen testing for Guangzhou, China by limiting the number of allergens for which patients are tested, and provide a testing panel to improve diagnostic and therapeutic efficiency. This retrospective study of real-world data from 2012 to 2019 included 39,570 patients with suspected allergies in Guangzhou, southern China. All the patients were tested for one or more of the following allergens serum specific immunoglobulin E (sIgE): Dermatophagoides pteronyssinus, Dermatophagoides farinae, cat dander, dog dander, Artemisia vulgaris, Aspergillus fumigatus, Alternaria alternata, Blattella germanica, egg whites, milk, wheat, peanuts, soybeans, Cancer pagurus, and Penaeus monodon by PhadiaCAP 1000. Totally, only the positive rates of allergens sIgE in D. farinae, D. pteronyssinus, milk, egg whites, B. germanica, C. pagurus, A. alternata, and P. monodon were > 10%, the other allergens were between 4–7%. Moreover, among the allergic diseases, dust mites exhibited the overall highest positive rate, followed by milk and B. germanica. In children, milk was the main allergen, whereas in adults, mites, cockroaches, shrimp, and crab allergens had higher positive rates. The optimal scale analysis shows that the multiple sensitization classification of patients can be divided into three categories: I D. farinae and D. pteronyssinus; II. C. pagurus, P. monodon, and B. germanica; III. Milk and egg whites. Generally, a panel including 4 allergens can detect > 90% of the potential allergy in this local population. In Guangzhou, southern China, D. farinae, milk, B. germanica, and A. alternata as a panel screening allergy for suspected allergic patients was suggested base on this study. [ABSTRACT FROM AUTHOR]

For decades, changes in fish catch composition and the marine environment have been monitored worldwide and recorded in databases like FAO FishStatJ and the European Union Copernicus Marine Service. However, the complexity and high variability in the dataset makes it challenging to find meaningful information through conventional data analytical methods. Therefore, in this pilot data mining study, we employed association rule mining algorithms (Apriori, ECLAT, and FP-Growth) to find frequently occurring itemsets in the fish-catch composition and marine environment data of the west and east coasts of India during the past decade (2011-2020). Firstly, the inherent spatial and temporal variations in fish-catch composition and marine environment (sea surface temperature and chlorophyll) on the west and east coasts of India were statistically analyzed and described. Then, the data were preprocessed, selected, and transformed into categorical attributes. By applying the association rule mining algorithms written in the Python language in the Google Colab workspace, we obtained frequent itemsets of fish catch and marine environment with different levels of minimum support and confidence. The preliminary results showed linear and inverse associations between changes in the sea surface temperature, chlorophyll concentration, and major catch groups, such as anchovies, Indian oil sardine, Indian mackerel, hairtails, butterfish-pomfrets, Bombay duck, flatfish, tunas, giant tiger prawn, crabs, lobsters, and cephalopods. Among the tested data mining algorithms, FP-Growth was found to be more efficient and reliable in finding associations between the spatiotemporal dynamics of the marine environment and fish distribution and abundance. Therefore, it can be potentially used to support marine fisheries' resource assessment and management strategies after refinement. [ABSTRACT FROM AUTHOR]

Laranjeira et al.'s study evaluated the effects of extracts of the aromatic plant I Pterospartum tridendatum i , an important source of active compounds, in treating acute and chronic inflammation in adult rats using an experimental model of osteoarthritis and ear edema and correlated it with its phytochemical composition. Bioactive components are substances that positively influence the organism, resulting in a physiological benefit and/or reduction in the risk of developing certain pathologies. Ahmed et al. evaluated the effects of various plant matrices and their phytochemical compounds in terms of modulating the immune system and signaling pathways involved in anti-tumor immunity. The results show that this effect depends on the chemical structure of the antioxidant substances used, as some of them, working in combination with the field, show a strong anti-tumor effect, while others, such as resveratrol, lose their anti-tumor properties under the influence of a moderate-intensity static magnetic field [[2]]. [Extracted from the article]

Objectives: This study was to identify and characterize Decapod iridescent virus 1 (DIV1) in the outbreaks reported in two whiteleg shrimp farms and one black tiger shrimp farm located in northern Taiwan in 2020. Methods: The histopathology, electron microscopy and polymerase chain reaction (PCR) specific for the DIV1 were used to identify the virus, and the phylogenetic analysis was performed by comparing the major capsid protein gene fragment of DIV1s from Taiwan with reference sequences of the family Iridoviridae. Results: DIV1 was identified by diagnostic PCR and caused mild mortality (20%) in cultured Penaeus monodon and high mortality (100%) in cultured whiteleg shrimp. Cultured P. monodon was first found to be infected with DIV1 through natural route of infection. Histopathological examination showed dark‐eosinophilic cytoplasmic inclusions in the degenerative cells of targeted hematopoietic tissues. For electron microscopy, a non‐enveloped virus particle was observed from homogenates of mixed target organs through negative staining with a diameter of 112±2 nm. Nucleotide sequences of DIV1 isolates from the Taiwanese outbreak are 100% identical to those from the PRC. Conclusions: Based on the clinical evidence, mortality rates, histopathology, electron microscopy examinations and phylogenetic analysis, it is believed that DIV1 is the causative agent of the outbreak. This is the first report of DIV1 in cultured shrimp in Taiwan. The emergence of DIV1 signals a warning to shrimp aquaculture farmers worldwide. [ABSTRACT FROM AUTHOR]

Penaeus monodon (tiger shrimp), Metapenaeus monoceros (brown shrimp), and Fenneropenaeus indicus (white shrimp) are the most economically important shrimp species in the waters of the Bay of Bengal, Bangladesh. This is the first analytical study to assess three major shrimp stocks using both length-based and catch-based methods, such as length-based Bayesian biomass estimation (LBB), length-based indicator (LBI), and a catch-based method entitled JABBA (Just Another Bayesian Biomass Assessment), to explore and process the data; estimate the growth parameters, with length at first capture; present relative biomasses; and approximate the reference points. The parameters of the von Bertalanffy Growth Function (VBGF) analysis for the tiger, brown, and white shrimps were L∞ = 113.0 mm, 85.4 mm, and 76.4 mm, respectively, for carapace length. Our results showed that the relative biomass level (B/BMSY) of the tiger shrimp was 0.43, suggesting an overfished status, and brown and white shrimps were 0.84 and 0.96, indicating that they were fully exploited but not overfished. This study, therefore, advised an optimum carapace length limit to catch from 57.0–70.0 mm for tiger shrimp, 44.0–53.0 mm for brown shrimp, and 40.0–48.0 mm for white shrimp. The estimated maximum sustainable yield (MSY) reference points were as follows: optimal biomass BMSY = 3116 mt, 15,885 mt, and 2649 mt for tiger, brown, and white shrimp, respectively, and optimal harvest rate uMSY = 12%, 33%, and 8% for tiger, brown, and white shrimp, respectively. The average annual catch values for the last ten years were 265 mt, 2396 mt, and 115 mt below the estimated MSY values of 389 mt, 4899 mt, and 209 mt for tiger, brown, and white shrimp, respectively. But, brown shrimp had the estimated highest carrying capacity (31,770 mt) and intrinsic growth rate (0.66) than the tiger and white shrimp, which was replicated distinctly in the graphical representation of the Kobe plot and the surplus production plot. Hence, the brown shrimp stock is estimated to be in a better state than the tiger and white shrimp stocks. [ABSTRACT FROM AUTHOR]

Polysaccharide monooxygenases (PMOs) and Glycoside Hydrolases (GH) play a crucial role in breaking down chitin and cellulose. Research on PMOs has mainly focused on their role in the production of bioethanol from biomass. Still, the potential of PMOs as virulence factors in microorganisms is not been fully studied. Some pathogenic bacteria secrete PMOs, which have been identified as virulence factors. The ability of Vibrio species to metabolize chitin is well-known, but the question of which Vibrio species contains the PMO gene remains unanswered. Materials and methods: Black tiger shrimp Penaeus monodon was collected from a culture pond in Long An, Vietnam. Thiosulfate-citrate-bile salts-sucrose and CHROMagar Vibrio agar were used to isolate, Vibrio bacteria from the shrimp samples. Mixed bases primers were designed to detect PMOs gene from Vibrio strains. Results: Total of 35 different strains of bacteria were isolated from the guts and pancreas of the shrimp sample. Based on biochemical tests, there were a total of 20 different Vibrio strains identified among 35 isolated strains. The PCR results showed that six isolates could have the PMOs gene. The partial 16S rDNA fragments of six isolate Vibrio strains were sequenced. Comparing 16S rDNA sequences with sequences available in NCBI databases revealed that all the sequences are Vibrio spp. 16S rDNA sequences.