Shrimp Disease Research Articles

ISOLATION OF LACTIC ACID BACTERIA FROM VANAME SHRIMP (Litopenaeus vannamei) AND ITS ANTAGONISM TO PATHOGEN BACTERIA

Vaname shrimp is one of Indonesia's leading export species and is widely cultivated. The main problem in vaname shrimp pond cultivation is the attack of shrimp diseases caused by bacteria or viruses. This study aims to isolate and identify lactic acid bacteria (BAL) from vaname shrimp (Litopenaeus vannamei) and test their antagonism against pathogenic bacteria. The research was conducted from February to April 2023. The method used in this study is a survey method. Sampling was conducted at the vaname shrimp pond of the Fisheries Service Task Unit (UPT), Tanjung Punak Village, Rupat Utara District, Bengkalis Regency, Riau. The method used in this research was a survey method. BAL was isolated using MRS Agar + CaCO3 media. The Kirby-Bauer method was used to test bacterial antagonism against pathogenic bacteria. Based on the identification of seven isolates, it was found that only four isolates were positively identified as LAB bacteria, namely 47D, 54T1, 73DB1, and 73BD2. The results of the antagonism test against pathogenic bacteria showed that all BAL isolates could not suppress the growth of E. coli bacteria. However, these isolates suppressed the growth of A. hydrophila bacteria, with the widest inhibition zone diameter on isolate 54T1 (4.2 mm). On Vibrio sp. bacteria, the widest inhibition zone of BAL was on isolate 73DB1 (6 mm). These results indicate that the antibacterial activity produced by BAL is still relatively weak

Climatic events and disease occurrence in intensive Litopenaeus vannamei shrimp farming in the Mekong area of Vietnam

As recurrent disease outbreaks impart economic adversity across the global shrimp farming sector in general, and in Asia in particular, clarifying determinants of outbreak susceptibility carries significance for sustainability in economic growth and social and environmental prospects. This study employs logistic regression to assess the probability of disease occurrence in intensive white leg shrimp (WLS) (Litopenaeus vannamei) aquaculture under the impact of explanatory factors grouped in (1) farmers' perceptions of climatic events, (2) adaptation measures (3) farmer biodata, (4) farm site characteristics, (5) biosecurity measures, and (6) culture method. The analysis was performed using a survey of 267 Vietnamese small-scale intensive shrimp farms in the Mekong region. Significant contributors to lowering the chance of shrimp disease occurrence include (1) regularly carrying out feed conversion ratio calculations, (2) increasing participation in training programs and extension services, (3) implementing adaptive measures related to changes in feeding schedules, and (4) increasing stocking density. The main risk factors increasing the chance of shrimp disease are the duration of the crop and more years in operation. This quantitative evidence contributes to identifying important focal points for policymakers and intensive shrimp farmers in monitoring and managing the shrimp industry under the potential impacts of climate change.

Effects of Microplastic Exposure against White Spot Syndrome Virus Infection in Pacific White Shrimp (Penaeus vannamei).

Plastic waste has emerged as a major environmental concern in recent years. As plastic waste discharged into the marine environment, it undergoes a breakdown process, eventually accumulating in aquatic organisms in the form of microplastics (MPs). To date, reduced food intake, nutritional absorption, and impaired immune system are known adverse effects of MPs-exposed aquatic organisms. This study aims to investigate whether MP exposure accelerated white spot syndrome virus (WSSV) infection in Pacific white shrimp (Penaeus vannamei) via laboratory tests. Briefly, experimental shrimp were divided into four groups; WSSV (group 1); MP (group 2); WSSV + MP (group 3); and Control (group 4). No mortality was observed in group 2, group 4, and even in group 1. However, group 3 showed a cumulative mortality of 50% during the experimental period. The PCR assay results showed no WSSV in the other three groups (groups 1, 2, and 4), but the dead and alive shrimp collected from group 3 were confirmed to be infected with the virus. Histopathological examination revealed normal structures in the hepatopancreas, gill, and muscle tissues of group 4, whereas numerous abnormally shaped nuclei were detected in the gill tissue of group 2. Moreover, group 1 showed minor WSSV-related lesions with few basophilic inclusion bodies in the gills, interestingly, group 3 exhibited severe lesions with numerous basophilic inclusion bodies in the gills. In conclusion, this study confirmed the correlation between the viral disease of shrimp and MPs, which can cause significant economic losses to the shrimp aquaculture industry.

Survival, immune response and growth of Penaeid shrimp as affected by immunostimulants: A meta-analysis

Immunostimulants represent the most innovative approach for combating shrimp diseases. They are molecules that effectively enhance the host's nonspecific defenses against invading microorganisms. However, methodological differences exist among immunostimulants based on the same source. Therefore, conducting a meta-analysis is essential to derive valid conclusions. The effect size value utilized in this study was Hedges' d. Heterogeneity among studies was assessed using the DerSimonian and Laird tests (Q-statistic). Meta-regression analysis was conducted to explore the sources of heterogeneity in treatment effects. In this study, dose served as a covariate because it was the only continuous variable that significantly contributed to the observed heterogeneity. Funnel plots and the fail-safe number were employed to assess publication bias within the datasets. The article collection process followed the PRISMA methodology. Based on the results of the meta-analysis and meta-regression conducted with 83 articles, it can be concluded that immunostimulants have a significant effect, characterized by high category standard mean difference (SMD) values, on the survival, growth, and immune response of Penaeid family shrimp. Among potential immunostimulants options, algae ingredients exhibited the most favorable effects on the survival, growth, and immune response of Penaeid family shrimp. Subgroup analysis outcomes revealed that various extraction methods significantly impacted the efficacy of immunostimulants, with the ethanol solvent method proving to be the most effective. Among different administration methods, no significant effect was observed on immunostimulant efficacy across all parameters, with positive SMD values for all administration methods. Regarding challenged test pathogens, immunostimulants were observed to enhance immune response, survival, and weight gain against various pathogens. Meta-regression results indicated that algal treatments had a lower optimal dose point, leading to decreased efficacy as the dose increased. In contrast, fungi exhibited a higher optimum dose point, resulting in increased efficacy at higher doses.

Development of lateral flow immunoassay strip for rapid detection of acute hepatopancreatic necrosis disease-causing PirAB toxins in shrimp

Acute hepatopancreatic necrosis disease (AHPND) is currently the most affected disease of shrimp farms worlwide As rapid and specific detection methods are essential to improve disease management, a lateral flow immunoassay (LFIA) was designed for the detection of PirAvp and PirBvp toxins in shrimp. In this study, polyclonal antibody based lateral flow immunoassay (LFIA) strip has been developed. The recombinant PirAvp and PirBvp toxin‐like proteins of Vibrio parahaemolyticus (VPAHPND) was used to immunize rabbits with the highest antibody titre after the third booster. This polyclonal rabbit antiserum was purified and used to develop a LFIA strip for the detection of AHPND pathogen. This test strip could detect PirAvp and PirBvp toxins up to 125 ng/mL by naked eye within 15 min. No cross-reactivity was observed with VPnon-AHPND. Furthermore, the sensitivity and specificity of LFIA were 94.0% and 98.0%, respectively. This LFIA strip could be used as a handy tool by the farmers and technicians in situ. ® 2023 Journal of Science and Technology - NTTU

The effect of supplementation of Lactococcus lactis strain as probiotic on the growth and survival of Litopenaeus vannamei

Acute Hepatopancreatic Necrosis Disease (AHPND) or Early Mortality Syndrome (EMS) is a bacterial disease in shrimps caused by pathogen Vibrio parahaemolyticus. It has culminated in huge loss in global shrimp production due to mass mortality. A probiotic strain Lactococcus lactis strain FA1 was recently isolated from shark intestine, showing inhibition towards the growth of the pathogen. Due to inhibitory potential, the effect of probiotics strain on growth performance of shrimp infected with V. parahaemolyticus was evaluated. The probiotic strain was incorporated into feed for juvenile shrimps Litopanaeus vannamei for 3 weeks before which they were then challenged with pathogen Vibro parahaemolyticus. The study compares 4 shrimp groups: Control (Without any treatment); Group A (Probiotic treated, uninfected); Group B (Probiotic treated, infected) and Group C (No probiotic, infected). The survival and growth performance (weight and length gain) of shrimps were evaluated in the following 30 days. Statistical analyses (ANOVA; Post Hoc Tukey) were used to compare between shrimp groups. In general, infected shrimp demonstrated some of the key symptoms of AHPND (pale or white hepatopancreas), transparent body and erratic swimming behaviour. The supplementation of probiotics resulted in an improved survivability (65±1%) compared to infected shrimp (45±1%). The probiotic treated shrimp group showed to have better % body weight gain, in which weight gain between group B (treated/infected) and group C (untreated/infected) were significantly different (at P=0.046); and so, to group A (treated/uninfected) when compared with group C (P=0.047). There is however no significant difference in % length gain between the groups. Meanwhile, some of the infected shrimps were able to show recovery from the infection. Pre-infection probiotic treatment showed better performance compared to post-infection probiotic treatment. This indicated that the strain Lactococcus lactis is highly suitable for use as the future probiotic in shrimp aquaculture.

ZntA maintains zinc and cadmium homeostasis and promotes oxidative stress resistance and virulence in Vibrio parahaemolyticus

ABSTRACT Although metals are essential for life, they are toxic to bacteria in excessive amounts. Therefore, the maintenance of metal homeostasis is critical for bacterial physiology and pathogenesis. Vibrio parahaemolyticus is a significant food-borne pathogen that mainly causes acute gastroenteritis in humans and acute hepatopancreatic necrosis disease in shrimp. Herein, we report that ZntA functions as a zinc (Zn) and cadmium (Cd) homeostasis mechanism and contributes to oxidative stress resistance and virulence in V. parahaemolyticus. zntA is remarkably induced by Zn, copper, cobalt, nickel (Ni), and Cd, while ZntA promotes V. parahaemolyticus growth under excess Zn/Ni and Cd conditions via maintaining Zn and Cd homeostasis, respectively. The growth of ΔzntA was inhibited under iron (Fe)-restricted conditions, and the inhibition was associated with Zn homeostasis disturbance. Ferrous iron supplementation improved the growth of ΔzntA under excess Zn, Ni or Cd conditions. The resistance of ΔzntA to H2O2-induced oxidative stress also decreased, and its virulence was attenuated in zebrafish models. Quantitative real-time PCR, mutagenesis, and β-galactosidase activity assays revealed that ZntR positively regulates zntA expression by binding to its promoter. Collectively, the ZntR-regulated ZntA is crucial for Zn and Cd homeostasis and contributes to oxidative stress resistance and virulence in V. parahaemolyticus.

Multi-omics characterization and identification of small non-coding RNAs in Spiroplasma eriocheiris

Spiroplasma eriocheiris is the major pathogen in the aquaculture shrimp and crab tremor disease; its infection causes heavy losses in aquaculture. Previous investigations concentrated on how the host responds to S. eriocheiris infection, with little known on the regulation of virulence and pathogenesis by the bacteria themselves. A body of increasing evidence shows that bacterial small noncoding RNAs (sRNAs) play a crucial part in regulating bacterial virulence and pathogenesis; however, whether there are some sRNAs in S. eriocheiris and how those sRNAs regulate virulence and pathogenesis are still unclear. This study analyzed multi-omics data integration to identify the potential sRNAs and their mediated regulatory network in S. eriocheiris. First, through an integration analysis of the public genomic and transcriptomic data, 54 potential sRNAs were identified in S. eriocheiris with a 50–250 nt length distribution and the base composition mainly AT. Next, sRNA profiling of the in vitro logarithmic and decline phase of S. eriocheiris, as well as the early and onset stage of infection in Eriocheir sinensis, was performed, showing that 4 sRNAs (SR01, SR05, SR08, and S04) were both down-regulated in the logarithmic and the onset stage of infection. Subsequently, integrated with sRNAs target gene prediction and target gene expression analysis, a regulatory network composed of four sRNAs and 96 target genes was constructed. Last, an RNA pull-down experiment was performed on the SR01, which exhibited the highest abundance and the highest number of target genes, resulting in 37 highly credible target genes with multiple genes related to bacterial virulence, such as GTPases and virulence factor coding genes. Collectively, this study identified the sRNAs in S. eriocheiris and revealed their mediated regulatory network for regulating virulence and pathogenesis, thus paving a new avenue for disease prevention and control in aquaculture.

Morinda citrifolia fruit extract enhances the resistance of Penaeus vannamei to Vibrio parahaemolyticus infection

Vibrio parahaemolyticus is a gram-negative facultative anaerobic bacterium implicated as the causative agent of several shrimp diseases. As part of the effort to provide biocontrol and cost-effective treatments, this research was designed to elucidate the effect of Morinda citrifolia fruit extract on the immunity of Penaeus vannamei postlarvae (PL) to V. parahaemolyticus. The methanol extract of M. citrifolia was vacuum evaporated, and the bioactive compounds were detected using gas chromatography‒mass spectrometry (GC‒MS). Thereafter, P. vannamei PL diets were supplemented with M. citrifolia at different concentrations (0, 10, 20, 30, 40, and 50 mg/g) and administered for 30 days before 24 h of exposure to the bacterium V. parahaemolyticus. A total of 45 bioactive compounds were detected in the methanol extract of M. citrifolia, with cyclononasiloxane and octadecamethyl being the most abundant. The survival of P. vannamei PLs fed the extract supplement was better than that of the control group (7.1–26.7% survival greater than that of the control group) following V. parahaemolyticus infection. Shrimp fed 50 mg/g M. citrifolia had the highest recorded survival. The activities of digestive and antioxidant enzymes as well as hepatopancreatic cells were significantly reduced, except for those of lipase and hepatopancreatic E-cells, which increased following challenge with V. parahaemolyticus. Histological assessment of the hepatopancreas cells revealed reduced cell degeneration following the administration of the plant extracts (expecially those fed 50 mg/g M. citrifolia) compared to that in the control group. Therefore, the enhanced immunity against V. parahaemolyticus infection in P. vannamei could be associated with the improved hepatopancreas health associated with M. citrifolia fruit extract supplementation.

Acute Ammonia Causes Pathogenic Dysbiosis of Shrimp Gut Biofilms.

Acute ammonia exposure has detrimental effects on shrimp, but the underlying mechanisms remain to be fully explored. In the present study, we investigated the impact of acute ammonia exposure on the gut microbiota of the white shrimp Litopenaeus vannamei and its association with shrimp mortality. Exposure to a lethal concentration of ammonia for 48 h resulted in increased mortality in L. vannamei, with severe damage to the hepatopancreas. Ammonia exposure led to a significant decrease in gut microbial diversity, along with the loss of beneficial bacterial taxa and the proliferation of pathogenic Vibrio strains. A phenotypic analysis revealed a transition from the dominance of aerobic to facultative anaerobic strains due to ammonia exposure. A functional analysis revealed that ammonia exposure led to an enrichment of genes related to biofilm formation, host colonization, and virulence pathogenicity. A species-level analysis and experiments suggest the key role of a Vibrio harveyi strain in causing shrimp disease and specificity under distinct environments. These findings provide new information on the mechanism of shrimp disease under environmental changes.

Optimized swarming motility assay to identify anti-virulence products against Vibrio parahaemolyticus, a pathogen of farmed shrimp

Swarming motility is a type of movement used by pathogenic flagellated bacteria as virulence factor to colonize surfaces and cause damage to the host. Vibrio parahaemolyticus is a pathogenic flagellated bacterium that increases its virulence by switching from swimmer to swarming cells. The hosts of pathogenic V. parahaemolyticus include farmed shrimp. Therefore, methods to detect and quantify this movement are important to control shrimp diseases caused by pathogenic V. parahaemolyticus strains. We developed an optimized swarming motility assay by identifying the most optimal type of agar, and drying time of the culture medium, agar concentration and volume of the bacterial culture to achieve the fastest swarming motility during the migration of V. parahaemolyticus on Petri dishes during a 24-hour incubation period. The method includes data analysis that could be used as a tool to identify potential anti-virulence products by comparing the slopes of the linearized diameters of the swarming halos of bacteria treated with the products, as they migrate on Petri dishes over a 24-hour incubation period.Here we report:•A simple method for detection and quantification of swarming motility halos of V. parahaemolyticus bacteria.•A method that could be used as a tool to identify potential anti-virulence products.

SOSIALISASI PENINGKATAN KUALITAS PRODUKTIVITAS PANEN UDANG MELALUI PENGONTROLAN KADAR AIR BERBASIS IOT DI DESA KUALA CEURAPE

Pond water quality is the main factor for the survival and productivity of shrimp farming. Physical parameters such as temperature, salinity and water turbidity are the main indicators of pond water quality. Poor water quality can reduce appetite, growth rate, and increase the risk of disease in shrimp. To overcome this problem, an effective monitoring and control system is needed. The method used in implementing this community service activity covering observation, design and socialization of the use of IoT-based automatic water content control devices. The results showed that the device is effective in helping fishermen controlling water levels automatically, increasing efficiency and effectiveness. The technology used includes the Arduino Uno microcontroller, ultrasonic sensor, RTC, LCD, relay module, motor driver, and DC motor. This activity is expected to provide new knowledge for fishermen in increasing shrimp productivity and quality through automatic control of pond water.

Application of Bacillus Coagulans as Paraprobiotic Against Acute Hepatopancreatic Necrosis Disease in Shrimp.

Paraprobiotics, known as non-viable or ghost probiotics, have attracted attention for their benefits over live microbial cells. This study was designed to investigate the paraprobiotic effects of heat-killed Bacillus coagulans on the white leg shrimp Litopenaeus vannamei. The paraprobiotic formulation was prepared in three different concentrations including B. coagulans 1 (107 cells g-1 diet), B. coagulans 2 (108 cells g-1 diet), and B. coagulans 3 (109 cells g-1 diet) through heat inactivation method. Preliminary toxicity assessments revealed that post-larvae shrimps (mean weight ± SE: 0.025 ± 0.007g) treated with B. coagulans 1, 2 and 3 paraprobiotic formulations exhibited no mortality, confirming the non-toxic nature of the formulated diet. In a 90-day feeding trial involving juvenile shrimps (mean weight ± SE: 0.64 ± 0.05g), growth parameters and feed conversion ratios improved in all experimental groups. Subsequently, these shrimps were challenged with Vibrio parahaemolyticus, revealing that paraprobiotic-fed shrimps exhibited significant survival rate improvements. Oxidative stress-related enzyme activities, such as superoxide dismutase and catalase, increased in paraprobiotic-fed shrimps post-Vibrio challenge, while the challenged control group showed decreased activity (p < 0.001). Nitric oxide levels are also increased in paraprobiotic-treated shrimp, with B. coagulans 3 showing a significant rise in nitric oxide activity (p < 0.001). This study further demonstrated the positive impact of paraprobiotic treatment on digestive enzymes, immune-related parameters (e.g., total hemocyte count, prophenoloxidase, and respiratory burst activity), and overall disease resistance. These findings suggest that B. coagulans paraprobiotics have the potential to enhance antioxidant, antibacterial, and immune-related responses in L. vannamei, making them a valuable addition to shrimp aquaculture.

Prevalence investigation of translucent post-larvae disease (TPD) in China

In early 2020, the shrimp farming in China suffered a severe setback due to an outbreak of the translucent post-larvae disease (TPD) in Penaeus vannamei. The emerging disease was caused by a hypervirulent strain of Vibrio parahaemolyticus (VpTPD). Although some progress has been made in understanding virulence factors of VpTPD, the diversity and prevalence of TPD pathogen are still unclear. Therefore, this study was undertaken to systematically investigate the epidemiology of TPD in China. In this study, potentially pathogenic bacteria present in naturally infected shrimp samples were isolated, identified, and preserved firstly. The further investigation showed that different Vibrio species carrying the key virulence genes of VpTPD can infect post-larvae of P. vannamei and cause TPD, revealing the diversity of TPD pathogens, and the pathogenic Vibrio strains has been temporarily named as Vibrio causing TPD (VTPD). In addition, epidemiological surveillance based on TaqMan qPCR detection and histopathology techniques analysis showed that VTPD positive samples were detected in most shrimp aquaculture ponds in different shrimp aquaculture provinces of China, with prevalence rate exceeding 50% in some areas. And seawater cultured species such as P. vannamei and P. japonicus were more sensitive to VTPD and were more likely to be infected or carry it. Freshwater cultured shrimp such as Macrobrachium rosenbergii and Procambarus clarkii may not be affected by VTPD. However, shrimp bait organisms are still at risk of carrying or being infected with VTPD. The result suggests that VTPD is still prevalent and spreading in coastal shrimp farming areas in China, with a high risk of transmission. This effort of present study provided a basic epidemiological understanding as well as important technical insights for prevention and management of emerging shrimp diseases.

Development of lateral flow immunoassay strip for rapid detection of acute hepatopancreatic necrosis disease-causing PirAB toxins in shrimp

Acute hepatopancreatic necrosis disease (AHPND) is currently the most affected disease of shrimp farms worlwide As rapid and specific detection methods are essential to improve disease management, a lateral flow immunoassay (LFIA) was designed for the detection of PirAvp and PirBvp toxins in shrimp. In this study, polyclonal antibody based lateral flow immunoassay (LFIA) strip has been developed. The recombinant PirAvp and PirBvp toxin‐like proteins of Vibrio parahaemolyticus (VPAHPND) was used to immunize rabbits with the highest antibody titre after the third booster. This polyclonal rabbit antiserum was purified and used to develop a LFIA strip for the detection of AHPND pathogen. This test strip could detect PirAvp and PirBvp toxins up to 125 ng/mL by naked eye within 15 min. No cross-reactivity was observed with VPnon-AHPND. Furthermore, the sensitivity and specificity of LFIA were 94.0% and 98.0%, respectively. This LFIA strip could be used as a handy tool by the farmers and technicians in situ.&#x0D; ® 2023 Journal of Science and Technology - NTTU

Updated roles of the gut microbiota in exploring shrimp etiology, polymicrobial pathogens, and disease incidence.

Litopenaeus vannamei is the most extensively cultured shrimp species globally, recognized for its scale, production, and economic value. However, its aquaculture is plagued by frequent disease outbreaks, resulting in rapid and massive mortality. etiological research often lags behind the emergence of new diseases, leaving the causal agents of some shrimp diseases unidentified and leading to nomenclature based on symptomatic presentations, especially in cases involving co- and polymicrobial pathogens. Comprehensive data on shrimp disease statuses remain limited. In this review, we summarize current knowledge on shrimp diseases and their effects on the gut microbiome. Furthermore, we also propose a workflow integrating primary colonizers, "driver" taxa in gut networks from healthy to diseased states, disease-discriminatory taxa, and virulence genes to identify potential polymicrobial pathogens. We examine both abiotic and biotic factors (e.g., external and internal sources and specific-disease effects) that influence shrimp gut microbiota, with an emphasis on the "holobiome" concept and common features of gut microbiota response to diverse diseases. After excluding the effects of confounding factors, we provide a diagnosis model for quantitatively predicting shrimp disease incidence using disease common-discriminatory taxa, irrespective of the causal agents. Due to the conservation of functional genes used in designing specific primers, we propose a practical strategy applying qPCR-assayed abundances of disease common-discriminatory functional genes. This review updates the roles of the gut microbiota in exploring shrimp etiology, polymicrobial pathogens, and disease incidence, offering a refined perspective for advancing shrimp aquaculture health management.

Effects of a phytobiotic-based additive on the growth, hepatopancreas health, intestinal microbiota, and Vibrio parahaemolyticus resistance of Pacific white shrimp, Litopenaeus vannamei.

Vibrio genus is a common pathogen in aquaculture and causes acute hepatopancreatic necrosis disease (AHPND) and massive mortality of shrimp. Many studies have suggested that a single functional ingredient such as plant extract or organic acid can reduce the dependence on antibiotics and promote the growth and immunity of aquatic animals. In this study, we evaluated the effects of a phytobiotic-based compound additive (Sanacore® GM, SNGM), which had a successful trajectory of commercial application in fish farming. However, its effects on the hepatopancreas health and intestinal microbiota of shrimp after Vibrio challenge have not been well evaluated. In the present study, Pacific white shrimp were fed diets with or without supplementation of SNGM, and the SNGM grades were 0-g/kg (CON), 3-g/kg (SNGM3), and 5-g/kg (SNGM5) diets. The feed trial lasted 60 days, after which a Vibrio parahaemolyticus challenge was performed. The results showed that compared to the CON group, both the SNGM3 and SNGM5 groups had a significantly higher weight gain and a lower feed conversion ratio as well as higher survival after Vibrio parahaemolyticus challenge. In the growth trial, the SNGM3 group had a significantly increased total protein, albumin concentration, and acid phosphatase activity in hemolymph compared to the CON group. In the challenge experiment, the SNGM3 and SNGM5 groups had increased albumin and glucose contents as well as the activities of phenoloxidase, lysozyme, alkaline phosphatase, and superoxide dismutase in hemolymph. Both the SNGM3 and SNGM5 groups had improved morphology of the hepatopancreas and intestine. The SNGM5 group had alleviated gut microbiota dysbiosis induced by Vibrio infection by increasing the potential probiotic bacterium abundance (Shewanella) and decreasing the potential pathogenic bacteria abundance (Vibrio, Photobacteriuma, Pseudoalteromonas, and Candidatus_Bacilloplasma). In conclusion, the dietary phytobiotic-based additive at 3-g/kg level increased the growth and Vibrio parahaemolyticus resistance of Pacific white shrimp by promoting immune-related enzyme activities and improving the morphological structure of the hepatopancreas and intestine and the intestinal microbiota composition.

Enterocytozoon hepatopenaei Infection in Shrimp: Diagnosis, Interventions, and Food Safety Guidelines.

The emergence of disease in shrimp has governed much concern in food safety and security among consumers with the recent reports on hepatopancreatic microsporidiosis (HPM) caused by Enterocytozoon hepatopenaei (EHP). The microsporidians present in shrimp remain a silent pathogen that prevents optimal shrimp growth. However, the biggest threat is in its food safety concerns, which is the primary focus in ensuring food biosecurity and biosafety. Hence, the objective of this review is to summarise the current knowledge of EHP and its infection in shrimp with food safety concerns. This paper provides an analysis of the diagnostic methods for detecting EHP infections in shrimp aquaculture. Interventions with current molecular biology and biotechnology would be the second approach to addressing EHP diseases. Finally, a systematic guideline for shrimp food safety using diagnostic and intervention is proposed. Thus, this review was aimed to shed light on effective methods for the diagnosis and prevention of EHP infection in shrimp. We also include information on molecular and genomics tools as well as innate immune biomolecules as future targets in the intervention strategies on the microsporidsosis life cycle in shrimp and its environment. Overall, this will result in reduced disease outbreaks in shrimp aquaculture, ensuring the shrimp food safety in the future.

The Use of (O. Basilicum) Extract to Treat Litopenaeus vannamei Disease the Infected Bacteria Vibrio parahaemolyticus

This research aims to treat vaname shrimp disease infected with bacteriaVibrio parahaemolyticus. In this research, we used Completely Randomized Design (CRD) 4 treatments and 3 replications. The treatment being tested was the treatment of vaname shrimp disease by soaking in basil (O. basilicum) leaf extract with different concentrations, namely: Treatment A (0 mg/ml), treatment B (1.56 mg/ml), treatment C (3.12 mg/ml) and treatment D (12.5 mg/ml). The parameter observed was the number of bacterial coloniesV. parahaemolyticus maintenance media and in the hepatopancreas of vaname shrimp. Apart from that, observations were made on the survival rate of vaname shrimp and water quality parameters. The research results found that the best concentration in the treatment of diseaseV. parahaemolyticus in vaname shrimp at a concentration of 12.5 mg/ml with the lowest number of bacterial colonies in the rearing media, namely 1.20 x 102 CFU/ml. In the hepatopancreas of vaname shrimp, the lowest number of colonies was obtained at a treatment concentration of 12.5 mg/ml, namely 1.12 x 102 CFU/ml. The highest survival rate was obtained at a treatment concentration of 12.5 mg/ml of 86,67±5,77%. The range of water quality in research observations was obtained as follows salinity 28.72-29.05 ppt, temperature 26.71- 27.25OC, oxygen ranges from 5.72-7.81, pH 7.18-8.13 and ammonia 0.033-0.041ppm. Water quality during the research was in the optimal range for the life of vaname shrimp.

Parental training with phloroglucinol protects their offspring from biotic and abiotic stressors in Macrobrachium rosenbergii

Being one of the fastest growing high protein animal foods producing sector, shrimp and prawn aquaculture has increased in demand worldwide. However, disease outbreak is considered one of the most limiting factors in this industry. Among shrimp bacterial diseases, vibriosis is one of the most important bacterial diseases. Additionally, acute hepatopancreatic necrosis disease (AHPND) in shrimp has been responsible for significant losses globally for the past ten years or so. Hence, for future sustainable shrimp farming, broodstock management and production of high-quality shrimp seed becomes a prerequisite for this industry, as it is considered to contribute to health management in general. Being invertebrates, shrimp and prawn solely depend on their innate immune system to combat the invading pathogens. However, in recent years, there is an increasing number of studies claiming innate immune memory in invertebrates. This implies that priming with pathogens or environmental stress or immune elicitors could induce increased resistance. In a previous study using a brine shrimp model, it was demonstrated that phloroglucinol, a plant-derived heat-shock protein inducing compound increased stress resistance in the parental generation, a phenotype that was passed on to the next generations. Intrigued by this, the present study was conducted to expand and validate these observations in commercial prawn Macrobrachium rosenbergii. First, following exposure of M. rosenbergii animals (juveniles) to phloroglucinol, improved survival, later on in life, was observed. Most interestingly, in the next generation, M. rosenbergii F1 animals originating from phloroglucinol-treated parents showed an increased resistance against AHPND causing Vibrio parahaemolyticus and abiotic stress (lethal heat shock and ammonia stress). To the best of our knowledge, this is the first validation study of parental conditioning in any commercial shrimp/prawn species. It is anticipated that this study will facilitate future research and application of parental conditioning as a unique and powerful management strategy against prophylaxis of infectious diseases in the shrimp farming industry.