White Shrimp Penaeus Research Articles

Transcriptomic analysis of the hepatopancreas of white shrimp Penaeus vannamei following experimental infection with the Vibrio parahaemolyticus TJA114

The Pacific white shrimp (Penaeus vannamei) is an economic breeding species with the largest annual production of penaeid shrimp worldwide. Besides the V. parahaemolyticus strains causing acute hepatopancreatic necrosis disease (AHPND), the non-AHPND V. parahaemolyticus strains also cause severe disease leading to significant economic losses in the shrimp. A non-AHPND V. parahaemolyticus strain, named TJA114, isolated from P. vannamei with vibriosis exhibited strong pathogenicity toward the shrimp. To better understand the pathogenesis of P. vannamei in the early stage of non-AHPND V. parahaemolyticus infection, we performed mRNA sequencing for the hepatopancreas between the control and the V. parahaemolyticus-challenged groups at six hours post-infection. We identified 916 differentially expressed genes: 550 up-regulation and 366 down-regulation in the challenged shrimp. GO terms related to immunity and metabolism were annotated, including biological adhesion, response to stimulus, metabolic process, binding, and cellular process. KEGG pathways related to fatty acid elongation, C-type lectin receptor signaling and complement and coagulation cascades were significantly influenced by the V. parahaemolyticus infection. This study provides insights into the mechanisms by which P. vannamei responds to early infection with the non-AHPND V. parahaemolyticus.

Biofloc system supplemented by Pseudoalteromonas piscicida 1Ub protects the Pacific white shrimp Penaeus vannamei from Vibrio parahaemolyticus infection

This study aimed to evaluate the supplementation of the probiotic Pseudoalteromonas piscicida 1Ub to the biofloc system as an ecofriendly strategy for protecting white shrimp (Penaeus vannamei) from Vibrio parahaemolyticus infection. Shrimp with an average body weight of (0.50 ± 0.09) g were reared in 30 glass jars with a working volume of 2.5 L at a density of 20 ind/L. Shrimp were reared for 5 d for each treatment, which included the biofloc system without and with 106 colony forming unit (CFU) per mL probiotic. The regular clear water system was used as control. All treatment groups were challenged with 103, 105, and 107 CFU/mL V. parahaemolyticus. For the negative control, shrimp were reared without V. parahaemolyticus. The results showed that the density of V. parahaemolyticus cocultured with P. piscicida 1Ub decreased and the density of V. parahaemolyticus in rearing water and shrimp body in the probiotic-treated group was lower than that in the control group (P < 0.05). The survival and immune response (total hemocyte count, phagocytic activity, respiratory burst, phenoloxidase, and superoxide dismutase) of shrimp in the probiotic group was higher than that in the positive control (P < 0.05). Moreover, supplementing the biofloc system with the probiotic could protect shrimp hepatopancreas from damage caused by V. parahaemolyticus, regardless of bacterial density. Thus, the supplementation of the probiotic P. piscicida 1Ub in the biofloc system could significantly protect and increase the resistance of shrimp to V. parahaemolyticus infection.

Metabolic and osmoionic effects of the recombinant crustacean hyperglycemic hormone (rCHH-A) of the Pacific white shrimp Penaeus vannamei on specimens acutely exposed to extreme salinities

The crustacean hyperglycemic hormone (CHH) is a multifunctional neuropeptide that plays a central role in crustacean metabolism and physiology. Experiments were conducted to examine the metabolic and osmoionic capabilities of the white shrimp Penaeus vannamei injected with its recombinant CHH-A (rCHH-A) peptide and acutely transferred from iso- (26 ppt) to hypo- (10 ppt) and hyper-osmotic (40 ppt) conditions. Hemolymph glucose, protein, osmoregulatory capacity (OC), and ionoregulatory capacity (IC) for sodium, chloride, potassium, and calcium were evaluated at four post-injection times (0.5, 1, 2, and 24 h). The rCHH-A peptide had hyperglycemic activity in all salinity conditions, obtaining maximum values at 1 h post-injection. However, in shrimp transferred to hyper-osmotic condition, rCHH-A caused the most significant reductions in OC (2 h), chloride IC (2 h), and total proteins (0.5-2 h) compared to the phosphate-buffered saline (PBS) control. Contrastingly, in shrimp transferred to hypo-osmotic conditions, rCHH-A decreased OC significantly from 2-24 h, strongly decreased chloride and potassium IC at 1 h post-injection, and increased total protein concentration in the hemolymph (1-2 h) when compared to PBS control. Concerning calcium, the rCHH-A injection decreased calcium IC at 10 ppt (1 h) and 26 ppt (2 h), providing insight into a potential role for CHH-A in calcium regulation. The results suggest that glucose and protein mobilization could enhance energy for osmo-ionic regulation under extreme osmotic conditions. This research study contributed to understanding crustacean endocrinology in P. vannamei and related euryhaline crustaceans. Further research should be performed to understand the osmo- and ionoregulatory mechanisms of the different CHH variants in crustaceans exposed to other stress conditions and the relationship with intermediary energy metabolism regulation.

Hemato-immunological parameters can be influenced by microalgae addition and fish feed supplementation in the integrated rearing of Pacific white shrimp and juvenile Nile tilapia using biofloc technology

This study evaluated the effects of microalgae (Scenedesmus obliquus) addition and fish feed supplementation on hemato-immunological parameters of Pacific white shrimp (Penaeus vannamei) and juvenile Nile tilapia (Oreochromis niloticus) cultured in integration using biofloc technology for 62 days. The experiment was designed as a factorial design with two factors, totaling four experimental groups: (1) No addition of microalgae and no addition of fish feed; (2) no addition of microalgae and addition of fish feed; (3) addition of microalgae and no addition of fish feed; and (4) addition of microalgae and addition of fish feed. In all groups shrimp were fed according to a feeding table. Shrimp (2.16 ± 0.01 g) and fish (1.53 ± 0.12 g) were cultured under densities of 400 shrimp m−3 and 522 fish m−3 in 800 L and 90 L (useful volumes) tanks maintained under water recirculation. Microalgae was added two times a week for a final concentration of 5 mg L−1 in the units, while a commercial fish feed was provided at the rate of 1% of the fish biomass daily. At the end of the trial, the fish and shrimp were sampled for the hemato-immunological analyses. As regards the shrimp, there was a significant effect of the interaction on total hemocyte count (p < 0.05), in which the highest value occurred in the group with microalgae/no fish feed addition. There was also a significant effect of microalgae addition on serum protein (p < 0.05), with the highest values occurring in the treatments that employed microalgae. In the case of the fish, the monocyte count was significantly affected by the fish feed addition (p < 0.05), the highest values being observed when the feed was provided. There were also significant effects of the interaction and of microalgae addition on mean corpuscular volume and mean corpuscular hemoglobin concentration (p < 0.05), with the highest values occurring in the group that received microalgae but no fish feed and in the groups that did not receive microalgae, respectively. Overall, these results suggest an enhanced immunological status for the shrimp due to increases in total hemocyte count and high serum protein concentration when microalgae was added and an improved nutritional status for the fish that received feed due to increased circulating monocytes, along with possible greater erythrocyte stability when microalgae was added.

Benzoic Acid Inclusion Effects on Health Status and Growth Performance of Juvenile Pacific White Shrimp Penaeus vannamei

AbstractOrganic acids and their salts are used as additives in aquafeeds, as their participation in some metabolic pathways and energy generation in organisms increases the nutritional value. Benzoic acid (BA; C6H5‐COOH), a white crystalline substance with a chemical structure that contains carboxylic acid attached to a benzene ring, is naturally found in plant and animal tissues. It is one of the most used organic acids due to its antifungal properties, and it acts as a preservative for a variety of human consumption products. Additionally, it demonstrates health and growth benefits when included in feeds by modifying the energy metabolism, microbiota, and intestinal tract morphology. Information on BA inclusion in aquatic food is rare, and such information for Pacific white shrimp Penaeus vannamei is nonexistent. This study evaluated the effects on growth, survival, feed conversion ratio, energy content, and health status (through lipid quantification in the hepatopancreas, histological examination, and salinity stress tests) of Pacific white shrimp juveniles by including BA at different concentrations (0.0, 1.0, 1.5, and 2.0 g/kg) in a commercial feed. Diets with BA inclusion produced significant differences in the hepatosomatic index, hepatopancreas lipid content, and histopathological index value (reflecting damage to the hepatopancreas and antennal gland atrophy) at all BA concentrations. The lowest survival obtained was 94.44% at a BA concentration of 1.0 g/kg. The feed conversion ratio was in accordance with the range established by the Food and Agriculture Organization of the United Nations except for values obtained at 0 g/kg. Calorimetric analysis and BA detection in muscle revealed no significant differences between concentrations. Due to the results obtained in this study, the evaluated inclusions of BA are not recommended for use in juvenile Pacific white shrimp diets.

Effect of molasses supplementation on growth performance, water quality and microbial dynamics during indoor rearing of pacific white shrimp Penaeus vannamei Boone, 1931

A study was conducted with Pacific white-leg shrimp (Penaeus vannamei Boone, 1931) juveniles to ascertain the effect ofmolasses supplementation on the growth performance, culture environment and microbial dynamics of rearing water. Theweight gain at the end of the experiment of 55 days duration were significantly (p&lt;0.05) higher in molasses supplementedgroup (12.08±0.45 g) as compared to control (10.44±0.34 g). Apparent feed conversion ratio (AFCR) was found significantly(p&gt;0.05) lower in case of molasses supplemented group with higher survival percentage. Supplementation of molasses alsoimproved the rearing water quality. The total ammonia nitrogen (TAN) level was significantly (p&lt;0.05) lower in the rearingwater of molasses supplemented tank (2.213±0.165 ppm) compared to control (2.915±0.191 ppm). There was no significantdifference in total heterotrophic bacteria (THB) and total Vibrio (TV) load between the water of the two groups. However,the proportion of TV to THB was significantly lower in case of molasses supplemented group as compared to control. Thisstudy indicated that supplementation of molasses can significantly improve the growth performance of P. vannamei withbetter feed utilisation and also improves the water quality by reducing the level of toxic gas i.e. ammonia in water. Keywords: Ammonia, C:N ratio, Molasses, Vibrio

Genomic characterization and identification of virulence-related genes in Vibrio nigripulchritudo isolated from white leg shrimp Penaeus vannamei.

Vibrio nigripulchritudo causes vibriosis in penaeid shrimps. Here, we used Illumina and Nanopore sequencing technologies to sequence the genomes of three of its strains (TUMSAT-V. nig1, TUMSAT-V. nig2, and TUMSAT-V. nig3) to explore opportunities for disease management. Putative virulence factors and mobile genetic elements were detected while evaluating the phylogenetic relationship of each isolated strain. The genomes consisted of two circular chromosomes (I and II) plus one or two plasmids. The size of chromosome I ranged from 4.02 to 4.07 Mb with an average GC content of 46%, while the number of predicted CDSs ranged from 3563 to 3644. The size of chromosome II ranged from 2.16 to 2.18 Mb, with an average GC content of 45.5%, and the number of predicted CDSs ranged from 1970 to 1987. Numerous virulence genes were identified related to adherence, antiphagocytosis, chemotaxis, motility, iron uptake, quorum sensing, secretion systems, and toxins in all three genomes. Higher numbers of prophages and genomic islands found in TUMSAT-V. nig1 suggest that the strain has experienced numerous horizontal gene transfer events. The presence of antimicrobial resistance genes suggests that the strains have multidrug resistance. Comparative genomic analysis showed that all three strains belonged to the same clade.

Responses of bacterial and three sub-microeukaryote communities in the water of white shrimp Penaeus vannamei aquaculture ponds in two polyculture models.

Polyculture operations in freshwater aquaculture ponds can disrupt microbial communities. High-throughput sequencing was used to assess the impact of polyculture operations on bacterial and three sub-microeukaryote communities (fungi, zooplankton, and eukaryotic phytoplankton) in Penaeus vannamei aquaculture ponds containing oriental river prawns and giant freshwater prawns, respectively. The results showed that the bacterial community was less sensitive than the microeukaryote communities to both the polyculture activity and environmental variations. The polyculture of giant freshwater prawns rather than oriental river prawns was the primary factor affecting the beta diversity of the three sub-microeukaryote communities. This may be due to the larger biomass of the polyculture varieties of giant freshwater prawns compared with oriental river prawns. The polyculture activity of giant freshwater prawns with a higher density and that of oriental river prawns with a lower density increased the stochasticity of the community assembly of the three sub-microeukaryote communities. It also affected the topological properties of the microbial communities, including greater correlations between ecosystem elements, and reducing the correlations among zooplanktons. The eukaryotic phytoplankton was the only microbial community that could also be explained by nutrient variation (mainly the total nitrogen). This highlights the potential role of the eukaryotic phytoplankton as a suitable indicator of the effects of nutrient input into ecosystems.

Lactobacillus plantarum isolated from kefir enhances immune responses and survival of white shrimp (Penaeus vannamei) challenged with Vibrio alginolyticus

Lactobacillus plantarum is known for its probiotics benefit to host, although the effects vary among strains. This study conducted a feeding experiment of three Lactobacillus strains, MRS8, MRS18 and MRS20, which were isolated from kefir and incorporated into the diets of shrimp to evaluate the effects of non-specific immunity, immune-related gene expression, and disease resistance of white shrimp (Penaeus vannamei) against Vibrio alginolyticus. To prepare the experimental feed groups, the basic feed was mixed with different concentrations of L. plantarum strains MRS8, MRS18, and MRS 20, which were incorporated at 0 CFU (control), 1 × 106 CFU (groups 8–6, 18–6, and 20–6), and 1 × 109 CFU (groups 8–9, 18–9, and 20–9) per gram of diet for an in vivo assay. During the rearing period for 28 days of feeding each group, immune responses, namely the total hemocyte count (THC), phagocytic rate (PR), phenoloxidase activity, and respiratory burst were examined on days 0, 1, 4, 7, 14, and 28. The results showed that groups 20–6, 18–9 and 20–9 improved THC, and groups 18–9 and 20–9 improved phenoloxidase activity and respiratory burst as well. The expression of immunity-related genes was also examined. Group 8–9 increased the expression of LGBP, penaeidin 2 (PEN2) and CP, group 18–9 increased the expression of proPO1, ALF, Lysozyme, penaeidin 3 (PEN3) and SOD, and group 20–9 increased the expression of LGBP, ALF, crustin, PEN2, PEN3, penaeidin 4 (PEN4) and CP (p < 0.05). Groups 18–6, 18–9, 2–6, and 20–9 were further used in the challenge test. After feeding for 7 days and 14 days, Vibrio alginolyticus was injected into white shrimp and observed the shrimp survival for 168 h. The results showed that compared to the control, all groups improved the survival rate. Especially, feeding group 18–9 for 14 days improved the survival rate of white shrimp (p < 0.05). After the challenge test for 14 days, the midgut DNA of survival white shrimps was extracted to analyze the colonization of L. plantarum. Among the groups, (6.61 ± 3.58) × 105 CFU/pre shrimp of L. plantarum in feeding group 18–9 and (5.86 ± 2.27) × 105 CFU/pre shrimp in group 20–9 were evaluated by qPCR. Taken together, group 18-9 had the best effects on the non-specific immunity, the immune-related gene expression, and the disease resistance, which might be due to the benefit of the probiotic colonization.

Individual and synergistic effect of highly diluted bioactive compounds and probiotic actinomycetes on the growth and survival of juvenile shrimp Penaeus vannamei

The objective of this study was to evaluate two Streptomyces spp. probiotic strains (RL8 and N7) and four highly-diluted bioactive compounds (HDBC) in the growth, survival, and modulation of the microbial content in culture water and hepatopancreas of juvenile white shrimp Penaeus vannamei. An experimental design was applied with five treatments in triplicate, including T1: (RL8+N7); T2: [(ViP-7C+ViA-7C) + (PhA-7C+SiT-7C)]; T3: [(ViP-7C+ViA-7C) + (PhA-7C+SiT-7C) + (N7)]; T4: [(ViP-7C+ViA-7C) + (PhA-7C+SiT-7C) + (RL8)] and T5 as the control without actinobacteria or HDBC. T2 showed significant differences (P &lt; 0.5) in height increase compared to the other treated and control groups. The organisms in T2, T3, and T4 recorded higher weight gain compared to T1 and T5. A survival rate from 94.13 ± 2.12 to 99.01 ± 2.45% was obtained with a significant difference (P &lt; 0.05) between T1, T2, and T3, concerning the untreated control (T5). A significant decrease in Vibrio spp. the content was observed in water and shrimp in T1 and T2 concerning the control. The heterotrophic bacterial count in hepatopancreas increased with all treatments compared to T5. Our results suggest a positive synergy between the HDBC mixture [(ViP-7C+ViA-7C) + (PhA-7C+SiT-7C)] and N7 Streptomyces sp. strain, whose probiotic action has been previously demonstrated by improving culture conditions for P. vannamei juveniles in terms of growth, survival, and reduction of potentially pathogenic bacteria.

Identification techniques to prevent the current emerging disease hepatopancreatic microsporidiosis in white shrimp Penaeus vannamei: an overview

Aquaculture combines techniques for breeding and harvesting aquatic organisms used in shrimp production. It is important as a source of income and for generating foreign exchange in the regions where it is practiced. However, the timely detection of diseases continues to be a great challenge for aquaculture and fisheries production. In recent years, Enterocytozoon hepatopenaei (EHP) has emerged as a major pathogen of the Pacific white shrimp Penaeus vannamei in many Asian countries (Vietnam, China, Indonesia, Malaysia, Thailand, India, and Korea). In Latin America, only in Venezuela, and to date, there is no report of its presence in Mexico. It is transmitted directly from shrimp to shrimp by oral or fecal means, cannibalism, or exposure to contaminated water. Hepatopancreatic microsporidiosis (HPM) is mainly associated with stunted growth and severe infections that can cause a poor production cycle, mortality, and problems in larva-producing laboratories. This review aims to overview the main microsporidian parasites and diseases found in white shrimp, including the clinical signs, control and prevention measures for EHP infection, and the detection of HPM using different techniques. In order to offer timely detection tools, different techniques are available for the detection and study of microsporidia. Such as optical microscopy, transmission electron microscopy, and histology; however, for diagnostic purposes, molecular methods are preferred due to their sensitivity, specificity, and short-time analysis. Our review suggests that constant monitoring in shrimp hatcheries and farms is essential to avoid the entry or transference of infected organisms, affecting shrimp production and the ideal development of healthy shrimp.

Shrimp Glucose-6-phosphatase 2 (G6Pase 2): a second isoform of G6Pase in the Pacific white shrimp and regulation of G6Pase 1 and 2 isoforms via HIF-1 during hypoxia and reoxygenation in juveniles.

Animals suffer hypoxia when their oxygen consumption is larger than the oxygen available. Hypoxia affects the white shrimp Penaeus (Litopenaeus) vannamei, both in their natural habitat and in cultivation farms. Shrimp regulates some enzymes that participate in energy production pathways as a strategy to survive during hypoxia. Glucose-6-phosphatase (G6Pase) is key to maintain blood glucose homeostasis through gluconeogenesis and glycogenolysis. We previously reported a shrimp G6Pase gene (G6Pase1) and in this work, we report a second isoform that we named G6Pase2. The expression of the two isoforms was evaluated in oxygen limited conditions and during silencing of the transcription factor HIF-1. High G6Pase activity was detected in hepatopancreas followed by muscle and gills under good oxygen and feeding conditions. Gene expression of both isoforms was analyzed in normoxia, hypoxia and reoxygenation in hepatopancreas and gills, and in HIF-1-silenced shrimp. In fed shrimp with normal dissolved oxygen (DO) (5.0mg L- 1 DO) the expression of G6Pase1 was detected in gills, but not in hepatopancreas or muscle, while G6Pase2 expression was undetectable in all three tissues. In hepatopancreas, G6Pase1 is induced at 3 and 48h of hypoxia, while G6Pase2 is down-regulated in the same time points but in reoxygenation, both due to the knock-down of HIF-1. In gills, only G6Pase1 was detected, and was induced by the silencing of HIF-1 only after 3h of reoxygenation. Therefore, the expression of the two isoforms appears to be regulated by HIF-1 at transcriptional level in response to oxygen deprivation and subsequent recovery of oxygen levels.

A novel Toll receptor from Pacific white shrimp Penaeus vannamei is involved in immune defense against Vibrio parahaemolyticus infection

Tolls/Toll-like receptors (TLRs) are a group of pattern recognition receptors (PRRs) that play central roles in the regulation of immune responses by sensing invading pathogens and initiating the downstream signaling pathways. In this study, a novel Toll (Toll10) from pacific white shrimp Penaeus vannamei has been identified and functionally studied in the context of immunity to bacterial infection. Toll10 has a series of tandem leucine-rich repeats (LRR) in the extracellular region but not a Toll/interleukin-1(IL-1) receptor homologous region (TIR) in the intracellular region. The Toll10 protein mainly locates on the cell membrane and its expression is up-regulated upon bacterial infection. The recombinant Toll10 protein can directly bind bacteria, and silencing of Toll10 increases the susceptibility of shrimp to Vibrio parahaemolyticus infection and inhibits the phagocytosis of V. parahaemolyticus by hemocytes. Moreover, Toll10 promotes the phosphorylation and nuclear translocation of the NF-κB family member Dorsal and positively regulates the expression of Dorsal-targeted antimicrobial peptide genes. This indicates that Toll10 mediates a signaling pathway to activate Dorsal and is important for antibacterial immune response in P. vannamei. The current study is helpful for the revelation of the regulatory mechanism of immune defense in shrimp against V. parahaemolyticus infection.

Improving red-color performance, immune response and resistance to Vibrio parahaemolyticus on white shrimp Penaeus vannamei by an engineered astaxanthin yeast

Astaxanthin (AST), a super antioxidant with coloring and medical properties, renders it a beneficial feed additive for shrimp. This study conducted a white shrimp feeding trial of 3S, 3’S isoform AST, which was derived from metabolic-engineered Kluyveromyces marxianus fermented broth (TB) and its extract (TE) compared to sources from two chemically synthetic ASTs (Carophyll Pink [CP] and Lucantin Pink [LP]), which contain 3S, 3’S, 3R, 3’S (3S, 3’R) and 3R, 3’R isoforms ratio of 1:2:1. The effects on red coloration, immune parameters and resistance to Vibrio infection were evaluated. Four AST sources were incorporated into the diets at concentrations of 0 (control), 100 mg kg−1 (TB100, TE100, CP100, and LP100), and 200 mg kg−1 (TB200, TE200, CP200, and LP200). Results revealed that in week 4, shrimps that received AST-supplemented feeds, especially TB100, TB200, and TE200, significantly increased redness (a*) values. Immune responses including phagocytosis activity, superoxide-anion production, phenoloxidase activity, and immune-related genes were examined on days 0, 1, 2, 4, 7, 14, 21, and 28. Generally, shrimps that received AST-supplemented feeds exhibited higher immune responses on days 7 and 14 than the control feed. Gene expression levels of superoxide dismutase and glutathione peroxidase were significantly upregulated on days 7 and 14 in shrimps that received AST-supplemented feeds, while genes of penaeidins, antilipopolysaccharide factor, and lysozyme were upregulated on days 4, 7, and 14, especially received TB200 and TE200. Furthermore, shrimps that received TB100, TE100, CP100, and LP100 7 days were then challenged with Vibrio parahaemolyticus and the result demonstrated higher survival rates especially TB100 at 168 h than the control feed. In conclusion, incorporating AST into the diets enhanced shrimp red coloration, immune parameters, and resistance against V. parahaemolyticus infection. The K. marxianus-derived AST exhibited higher performance than did chemical AST to be a potential feed additive in shrimp aquaculture.

Coinfection with Yellow Head Virus Genotype 8 (YHV-8) and Oriental Wenrivirus 1 (OWV1) in Wild Penaeus chinensis from the Yellow Sea.

At present, there are few studies on the epidemiology of diseases in wild Chinese white shrimp Penaeus chinensis. In order to enrich the epidemiological information of the World Organisation for Animal Health (WOAH)-listed and emerging diseases in wild P. chinensis, we collected a total of 37 wild P. chinensis from the Yellow Sea in the past three years and carried out molecular detection tests for eleven shrimp pathogens. The results showed that infectious hypodermal and hematopoietic necrosis virus (IHHNV), Decapod iridescent virus 1 (DIV1), yellow head virus genotype 8 (YHV-8), and oriental wenrivirus 1 (OWV1) could be detected in collected wild P. chinensis. Among them, the coexistence of IHHNV and DIV1 was confirmed using qPCR, PCR, and sequence analysis with pooled samples. The infection with YHV-8 and OWV1 in shrimp was studied using molecular diagnosis, phylogenetic analysis, and transmission electron microscopy. It is worth highlighting that this study revealed the high prevalence of coinfection with YHV-8 and OWV1 in wild P. chinensis populations and the transmission risk of these viruses between the wild and farmed P. chinensis populations. This study enriches the epidemiological information of WOAH-listed and emerging diseases in wild P. chinensis in the Yellow Sea and raises concerns about biosecurity issues related to wild shrimp resources.

Glucose addition improves the culture performance of Pacific white shrimp by regulating the assembly of Rhodobacteraceae taxa in gut bacterial community

The family Rhodobacteraceae is a major core bacterial group in the gut of Pacific white shrimp (Penaeus vannamei) and its abundance can be stimulated by the carbohydrates (e.g., glucose) addition in biofloc-based culture systems. However, how glucose addition regulates Rhodobacteraceae assembly at a fine taxonomic resolution and its relationship with shrimp culture performance are unclear. Here, using full-length 16S rRNA gene PacBio sequencing, we explored fine-scale assembly mechanism of gut Rhodobacteraceae regulated by glucose addition. Glucose addition significantly enhanced the growth, survival rate, and feed efficiency of shrimps, and induced Rhodobacteraceae assembly consequently to create a more stable gut bacterial community, reflected by enhanced convergence and network stability as compared to those of the control. Five Ruegeria taxa were identified as potential probiotic candidates for improving shrimp culture performance. Meanwhile, the neutral model showed that positive host selection of gut Ruegeria taxa (primarily R. conchae and R. arenilitoris) from both water and gut metacommunities was enhanced by glucose addition, which stimulated deterministic assembly of gut Rhodobacteraceae. Moreover, differences in assembly processes of Rhodobacteraceae taxa at presumed strain-level within the same species (i.e., R. conchae) were observed, suggesting the necessity of revealing aquaculture bacterial assembly at the finer taxonomic resolution. Collectively, structural equation modeling demonstrated glucose addition improved shrimp culture performance largely by regulating the gut Rhodobacteraceae assembly. Our study provides insights into the assembly of gut Rhodobacteraceae stimulated by a basic regulatory measure in biofloc-based culture systems, holding the practical potential in managing a beneficial microbiota for shrimp culture.

In silico prediction of potential indigenous microbial biomarkers in Penaeus vannamei identified through meta-analysis and genome-scale metabolic modelling

BackgroundUnderstanding the microbiome is crucial as it contributes to the metabolic health of the host and, upon dysbiosis, may influence disease development. With the recent surge in high-throughput sequencing technology, the availability of microbial genomic data has increased dramatically. Amplicon sequence-based analyses majorly profile microbial abundance and determine taxonomic markers. Furthermore, the availability of genome sequences for various microbial organisms has prompted the integration of genome-scale metabolic modelling that provides insights into the metabolic interactions influencing host health. However, the analysis from a single study may not be consistent, necessitating a meta-analysis.ResultsWe conducted a meta-analysis and integrated with constraint-based metabolic modelling approach, focusing on the microbiome of pacific white shrimp Penaeus vannamei, an extensively cultured marine candidate species. Meta-analysis revealed that Acinetobacter and Alteromonas are significant indicators of "health" and "disease" specific taxonomic biomarkers, respectively. Further, we enumerated metabolic interactions among the taxonomic biomarkers by applying a constraint-based approach to the community metabolic models (4416 pairs). Under different nutrient environments, a constraint-based flux simulation identified five beneficial species: Acinetobacter spWCHA55, Acinetobacter tandoii SE63, Bifidobacterium pseudolongum 49 D6, Brevundimonas pondensis LVF1, and Lutibacter profundi LP1 mediating parasitic interactions majorly under sucrose environment in the pairwise community. The study also reports the healthy biomarkers that can co-exist and have functionally dependent relationships to maintain a healthy state in the host.ConclusionsToward this, we collected and re-analysed the amplicon sequence data of P. vannamei (encompassing 117 healthy and 142 disease datasets). By capturing the taxonomic biomarkers and modelling the metabolic interaction between them, our study provides a valuable resource, a first-of-its-kind analysis in aquaculture scenario toward a sustainable shrimp farming.

Comparative study on the survival and growth performance of white shrimp Penaeus vannamei in ponds cultured with hatchery and nursery reared post larvae

Comparative study on the survival and growth performance of white shrimp Penaeus vannamei in ponds cultured with hatchery and nursery reared post larvae

Biokonsentrasi Timbal Dan Kadmium Terhadap Penaeus merguiensis Dalam Air Dan Sedimen Di Perairan Desa Sungsang I

Sungsang Village is located at the mouth of the Musi River making this area dense with settlements and transportation activities, this contributes to damage and results in decreased water quality. This study aims to analyze the concentrations of Pb and Cd in water, sediment and white shrimp (Penaeus merguiensis) and examine the level of accumulation of Pb and Cd through the BCF values of Pb and Cd in white shrimp (Penaeus merguiensis) in water and sediment in the waters of Sungsang I Village. Results the study showed that the average concentration of Pb in water in the waters of Sungsang I Village was 0.104 mg/L, exceeding the threshold value in Kep.Minister of State for the Environment No. 51 of 2004. The average Pb content in sediments is 24.892 mg/Kg, still below the quality standards of the Guidelines for the Protection and Management of Aquatic Sediment Quality in Ontario. The average concentration of Pb in jerbung shrimp is 0.809 mg/Kg, this value exceeds the limit set by BPOM. The results of the Cd test showed that the average water content, sediment, and jerbung shrimp were 0.013 mg/L, 0.174 mg/Kg and 0.127 mg/Kg. The BCF Pb value of shrimp-sediment was 7.779 and BCF Pb of shrimp-sediment was 0.033. The BCF Cd of shrimp-sediments was 9.769 and the BCF Cd of shrimp-sediments was 0.730. The Pb and Cd bioconcentration values of the jerbung shrimp (Penaeus merguiensis) in water and sediment are included in the low accumulative category, because the BCF value is &lt;100.

Dietary supplementation of synbiotic Leuconostoc mesenteroide B4 and dextran improves immune regulation and disease resistance of Penaeus vannamei against Vibrio parahaemolyticus

White shrimp (Penaeus vannamei) is an important culture species in Taiwan but often encounters disease infection by Vibrio parahaemolyticus that cause acute hepatopancreatic necrosis disease (AHPND). This study investigates the effects of dietary supplementation of Leuconostoc mesenteroide B4 and its fermentate (dextran) on the immune response, intestinal morphology, disease resistance, and immune-related gene expression in white shrimp. In comparison to the control group, the shrimp fed with a diet containing B4+dextran (107 CFU B4/g feed and 0.05% dextran) for 14, 28, 42 and 56 days had a significantly higher feed efficiency, weight gain and specific growth rate. A significantly higher villus height in the intestine and higher survival rate after challenging with V. parahaemolyticus was recorded for the B4+dextran group. Flow cytometry analysis demonstrated that the group that had ingested B4+dextran had a higher total hemocyte count and a higher proportion of semi-granulocytes, but a lower percentage of granulocytes compared to the control group.The shotgun metagenomic results in the midgut revealed that Leuco. mesenteroides was barely found in the midgut of the shrimp, suggesting that this microbe and its transient presence in the midgut is not the direct mechanism underlying the improved shrimp growth in the treated sample. Instead, dextran, a key ingredient in the B4 fermentate, on the dynamic of the microbial populations in shrimp, possibly promoting the diversity of gut microbes, especially the beneficial microbes, and thereby rendering protection against AHPND.In terms of comparing the gene expression between the control and synbiotic groups, pre- and post-bacterial challenge, a higher expression level of immune genes was mostly found in the B4+dextran group after challenging it with V. parahaemolyticus (group B4+dextran-VP) in the hepatopancreas and hemocyte. In contrast, the transcript level of immune-related genes was found to be higher in the B4+dextran group than other combinations in the midgut.Taken together, this study found that dietary addition of synbiotic Leuco. mesenteroides B4 and dextran can improve the growth performance, intestinal morphology and microbiome, regulation of immune genes and disease resistance against V. parahaemolyticus infection in white shrimp.