Shrimp Farming Industry Research Articles

Shrimp laccase degrades polycyclic aromatic hydrocarbons from an oil spill disaster in Brazil: A tool for marine environmental bioremediation

Our work aims to purify, characterize and evaluate a laccase from by-products of the shrimp farming industry (Litopenaeus vannamei) for the degradation of Polycyclic Aromatic Hydrocarbons (PAHs) from 2019 oil spill in Brazilian coast. The enzyme was purified by affinity chromatography and characterized as thermostable, with activity above 90 °C and at alkaline pH. In addition, the laccase was also tolerant to copper, lead, cadmium, zinc, arsenic, hexane and methanol, with significant enzymatic activation in acetone and 10 mM mercury. Concerning PAHs' degradation, the enzyme degraded 42.40 % of the total compounds, degrading >50 % of fluorene, C4-naphthalenes, C3-naphthalenes, C2-naphthalenes, anthracene, acenaphthene, 1-methylnaphthalene and 2-methylnaphthalene. Thus, this laccase demonstrated important characteristics for bioremediation of marine environments contaminated by crude oil spills, representing a viable and ecological alternative for these purposes.

Epigenetic Modulations for Prevention of Infectious Diseases in Shrimp Aquaculture.

Aquaculture assumes a pivotal role in meeting the escalating global food demand, and shrimp farming, in particular, holds a significant role in the global economy and food security, providing a rich source of nutrients for human consumption. Nonetheless, the industry faces formidable challenges, primarily attributed to disease outbreaks and the diminishing efficacy of conventional disease management approaches, such as antibiotic usage. Consequently, there is an urgent imperative to explore alternative strategies to ensure the sustainability of the industry. In this context, the field of epigenetics emerges as a promising avenue for combating infectious diseases in shrimp aquaculture. Epigenetic modulations entail chemical alterations in DNA and proteins, orchestrating gene expression patterns without modifying the underlying DNA sequence through DNA methylation, histone modifications, and non-coding RNA molecules. Utilizing epigenetic mechanisms presents an opportunity to enhance immune gene expression and bolster disease resistance in shrimp, thereby contributing to disease management strategies and optimizing shrimp health and productivity. Additionally, the concept of epigenetic inheritability in marine animals holds immense potential for the future of the shrimp farming industry. To this end, this comprehensive review thoroughly explores the dynamics of epigenetic modulations in shrimp aquaculture, with a particular emphasis on its pivotal role in disease management. It conveys the significance of harnessing advantageous epigenetic changes to ensure the long-term viability of shrimp farming while deliberating on the potential consequences of these interventions. Overall, this appraisal highlights the promising trajectory of epigenetic applications, propelling the field toward strengthening sustainability in shrimp aquaculture.

Prevalence of multi-antibiotics resistant (MAR) Vibrio parahaemolyticus in shrimp farms in Sarawak, Malaysia

The shrimp farming industry is constantly under threat due to outbreaks of infectious diseases and environmental problems. Vibrio parahaemolyticus is an important foodborne pathogen causing significant economic losses within the shrimp aquaculture industry worldwide. This research aimed to determine the prevalence of V. parahaemolyticus from different shrimp farms from the stocking to harvesting period and assess the antibiotic susceptibility of V. parahaemolyticus using the antimicrobial susceptibility test (AST). In this study, a total of 288 samples comprising twenty-four from each sample consisting of shrimp, water, effluent, and sediment samples were collected aseptically from three (n = 3) shrimp farms located at Telaga Air Farm 1 (Pond 6), Telaga Air Farm 2 (Pond 9) and Santubong Farm (Pond 7), Kuching, Sarawak. A molecular approach by polymerase chain reaction was used to confirm the presence of regulator gene, toxR, V. parahaemolyticus. A total of 14 antibiotics, including spectinomycin (SH100), imipenem (IPM10), amoxycillin/ clavulanic acid (AMC30), enrofloxacin (ENR5), bacitracin (B10), meropenem (MEM10), cephalothin (KF30), penicillin G (P10), tetracycline (TE30), kanamycin (K30), streptomycin(S25), rifampicin (RD2), erythromycin (E15), and nalidixic acid (NA30) were used. The results obtained showed that 51/288 (17.71%) of the collected samples with regulator gene, toxR V. parahaemolyticus. As a whole, this includes 31.25% (30/288) from sediment samples, 4.17% (4/288) from shrimp samples, 15.63% (15/288) from water samples, and 2.08% (2/288) from effluent water samples. A total of 54.9% (28/51) of V. parahaemolyticus acquired multiple antibiotic resistance (MAR). The resistance of antibiotics was profiled, and the multiple antibiotic resistance (MAR) indexes and classified into ten patterns. The MAR index of V. parahaemolyticus isolates ranged from 0.11 to 0.36. Vibrio parahaemolyticus isolates showed 31.38% with a MAR index > 0.2, indicating that these isolates might be originated from high-risk sources. The data obtained from this study is helpful to monitor the presence of V. parahaemolyticus in the aquaculture farm management system to mitigate the hazard potentially arising from the environmental factor that causes shrimp diseases and shrimp infection.

EVALUATION OF ENTEROCYTOZOON HEPATOPENAEI (EHP) IN FARMED PENAEUS VANNAMEI IN TAIWAN

Enterocytozoon hepatopenaei (EHP) was first described in Thailand in 2009 and has since been identified as a significant threat to the shrimp aquaculture industry. Recently, intracellular microsporidia were identified as a causative agent of hepatopancreatic microsporidiosis (HPM). To date, HPM has been listed as an emerging threat to shrimp farming industries because of reduced shrimp growth and survival rates which are considered to be a wasting disease. This study investigated the outbreaks of HPM in farmed Penaeus vannamei in Taiwan. Sixty-five shrimp samples were collected from Taiwan. The proportion of HPM-positive cases was 48% (31/65). Additionally, the gross signs in infected shrimp were stunted growth, sloughed hepatopancreas (HP), and lethargy. The smear impression on the HP also revealed the existence of large EHP spores. Nested-PCR findings identified that 9 cases were confirmed to be positive for the EhSWP1 gene in the first step and 22 cases tested positive for the second step. Phylogenetic analysis of EHP from Taiwan showed 100% similarity to EHP from Thailand, India, and the United States. Histopathological analysis of the HP revealed haemocyte infiltration and the presence of EHP spores in the hepatopancreatic tubule epithelial cells. These results demonstrated that EHP is the main cause in shrimp farms in Taiwan.

Prediction of Successful Harvest of Vaname Shrimp Pond at PT FEI With Machine Learning Approach

The demand for shrimp from Indonesia continues to increase every year, thus creating greater interest in the shrimp farming industry. Although shrimp is relatively easy to farm, many variables affect the success of the harvest. The harvest in shrimp farming is calculated using % SR (Survival Rate). In our research, we used machine learning approaches, namely decision tree (DT) and k-Nearest Neighbor (KNN). DT and KNN will be used to predict whether we will have a successful harvest. From these predictions, we also provide suggestions for business improvements to utilize data. The expected result of such advice is that the business can improve its performance and get more consistent results.

Evaluation of a synbiotic formulation for water remediation in a shrimp pond.

In recent years, the use of probiotic bacteria has attracted the interest of the marine shrimp farming industry. However, there are certain limitations pertaining to the practical application of many commercially available probiotics. Here, a thoroughly screened optimal consortium of three indigenous sulfur probiotics was tested for antibiotic susceptibility and was found to be safe, with each culture being sensitive to all the tested antibiotics. Further, de-potash vinasse (DPV), an environmental hazard, was tested for its prebiotic potential, and its 1% (w/v) concentration was found to be effective for long-term viability (> 66days) of the probiotic cultures and safe for Artemia. The synbiotic formulation was tested first in a lab-scale microcosm setup successfully and subsequently tried on a shrimp farm; it was observed that the product was congruent to the efficiency of a commercial probiotic regarding almost all physicochemical parameters, sulfide, nitrate-N, nitrite-N, phytoplankton sustenance, Pseudomonas count, coliform count, and heterotrophic count. In addition, it was significantly efficient in maintaining pH, reducing ammonia-N and phosphate-P, Vibrio and Aeromonas count, and a net increase in the yield of shrimp biomass by 625kg, thus proving to be a better alternative than one of the already available remediation methods.

The in silico and toxicity study of fraction red betel leaf (Piper crocatum) extract on histology lymphoid organ and hepatopancreas in white shrimp (Litopanaeus vannamei)

The shrimp farming industry has experienced a high mortality caused by diseases in recent decades. One of the most common diseases is vibriosis. This research aims is to obtain information on compounds found in fraction one of Piper crocatum as a therapeutic agent using in silico prediction and evaluate the toxicity test with an LC50. The potential of active ingredient content from P. crocatum extract was analyzed by in silico methods. The LC50 test was conducted by injections of the fraction one extract of P. crocatum for 96 hours at doses of 0 (control), 2 μg/g, 4 μg/g, 6 μg/g, 8 μg/g, and 10 μg/g. In silico toxicity (LD50) analysis showed that citral had the highest toxicity value (LD50) at 500 mg/kg and was classified as toxicity class 4, with an abundance value of 3.71%. The 10 μg/g concentration showed an LC50 mortality value of 53.3±5.8%. The percentage of heavy damage was observed at the concentration of 10 μg/g (53.33). These results indicate that the higher the concentration of fraction one extract of P. crocatum, the higher the percentage of damage to white shrimp's hepatopancreas and lymphoid organs.

Comparison of five commercial kits for isolation of total RNA in samples of WSSV-infected shrimp.

Viral diseases are the most serious threat to the expansion and development of shrimp aquaculture. Rapid diagnosis of the white spot syndrome virus (WSSV), a lethal shrimp pathogen, is essential to restrict its spread and reduce the mortality of infected shrimp. This virus has globally affected the shrimp farming industry, with a devastating economic impact. Several studies have focused on the expression of WSSV transcripts to understand the molecular mechanisms governing the pathological development of the disease. Since gene expression studies and molecular diagnostics at the early stages of infection depend on the efficient isolation of high-quality RNA, the extraction methods should be carefully selected. However, previous comparisons of the performance of RNA isolation kits have yet to be systematically investigated. In this study, 5 commercial RNA extraction methods were compared in WSSV-infected shrimp. The highest total RNA yield (ng mg-1 tissue) was obtained using TRIzol. Even though the 260/280 nm absorption ratios showed significant differences, the methods showed good purity values (>2.0). RNA integrity was evaluated in a denaturing agarose gel electrophoresis, and degradation was observed after the total RNA samples were treated with DNase I. Finally, the method that allowed the earlier detection of WSSV transcripts by qRT-PCR was the Zymo Direct-zol RNA MiniPrep kit. This study shows that the amount of observed (or estimated) WSSV transcripts might be affected because of the RNA isolation method. In addition, these results may contribute to improve the accuracy of the results obtained in gene expression studies, for more sensitive and robust detection of WSSV.

THE EFFECT OF IMMUNOSTIMULANTS FROM NATURAL INGREDIENTS ON VANAMEI SHRIMP (LITOPENAEUS VANNAMEI) IN INCREASING NON-SPECIFIC IMMUNITY TO FIGHT DISEASE

Vanamei shrimp Litopeneus vannamei is a commodity with high economic value. Shrimp is Indonesia's main export commodity. The high value of sales and production of vanamei shrimp is constrained by the many disease attacks in the vanamei shrimp farming industry. An alternative solution that has been continuously researched for several years to combat shrimp disease is using immunostimulants from natural ingredients. Using natural ingredients for immunostimulants can increase the non-specific immunity of vanamei shrimp to ward off disease and be environmentally friendly. Immunostimulants can be administered orally, by immersion, or by injection. Immunostimulants from natural ingredients such as spirulina platensis, polysaccharides from seaweed such as carrageenan, sodium alginate, and fucoidan, extracts from red seaweed, as well as the use of polysaccharides from the bacterium Nodulisporium sp. KT29, Trichoderma sp. able to increase the non-specific immune system in L. vannamei shrimp. These immunostimulants increase non-specific immunity, such as total hemocyte count, phagocytosis activity, phenoloxidase, phagocytic, respiratory burst, superoxide dismutase, and total plasma protein. Immunostimulants from these natural ingredients can also fight infectious disease attacks.

Antimicrobial Secondary Metabolites from the Mangrove Plants of Asia and the Pacific.

Microbes such as the White Spot Syndrome Virus account for severe losses in the shrimp farming industry globally. This review examines the literature on the mangrove plants of Asia and the Pacific with antibacterial, antifungal, or antiviral activities. All of the available data published on this subject were collected from Google Scholar, PubMed, Science Direct, Web of Science, ChemSpider, PubChem, and a library search from 1968 to 2022. Out of about 286 plant species, 119 exhibited antimicrobial effects, and a total of 114 antimicrobial natural products have been identified including 12 with MIC values below 1 µg/mL. Most of these plants are medicinal. The mangrove plants of Asia and the Pacific yield secondary metabolites with the potential to mitigate infectious diseases in shrimp aquaculture.

A one-pot RPA-CRISPR detection method for point-of-care testing of Enterocytozoon hepatopenaei infection in shrimp

The pathogen Enterocytozoon hepatopenaei (EHP) has significantly affected the shrimp farming industry since the last decade. For effective prevention, accurate and reliable detection methods for EHP infection are important, especially the methods suitable for point-of-care testing (POCT) environment. By combining recombinase polymerase amplification (RPA) with the CRISPR-Cas12a system, this study developed a POCT-friendly detection method for EHP infection with one-pot procedure. The combined method utilized robust amplification capacity of RPA and high specificity of CRISPR, thus had better accuracy and reliability. The one-pot procedure was achieved by careful design and screening of the crRNA and systematic optimization of the reaction. The issues related to the compatibility of RPA and Cas12a cleavage have been successfully solved. The method was highly specific and the sensitivity reached 101 gene copies per reaction. The practical performance was validated with clinical shrimp samples. With the generous temperature requirement and convenient end-point reading of results, the one-pot method is highly suitable for POCT environment. It is a good example of one-pot RPA-CRISPR detection assay for POCT purpose, and has great application value in prevention of EHP infection in shrimp farming industry.

Variability of White Spot Syndrome Virus (WSSV) Envelope Protein VP28 from Diseased Shrimp (Litopenaeus vannamei) in Indonesia

White Spot Disease (WSD) is a viral disease affecting crustaceans. Caused by the White Spot Syndrome Virus (WSSV), this disease has caused significant mortality in commercially cultivated marine shrimp species with severe impacts on the shrimp farming industry and may be a threat to wild shrimp stocks. Thorough studies on the molecular biology of this pathogen are urgently needed to improve understanding of the virus at a molecular level, including variation in key viral protein (VP) components of the WSSV virion. This study aimed to isolate and characterize WSSV VP28 gene encoding envelope proteins from Indonesian Pacific white shrimp (Litopenaeus vannamei) isolates. Infected juvenile shrimp were collected from Pangkep, Barru, and Pinrang Districts in South Sulawesi, Indonesia. Genomic DNA was isolated from infected shrimp muscle tissue using a DTAB-CTAB (dodecyle trimethyl ammonium bromide-hexadecyl trimethyl ammonium bromide) DNA extraction procedure. The WSSV VP28 DNA sequences from Pangkep, Barru, and Pinrang isolates were 640-680 bp in length. Homology of Pangkep isolates with isolates from Barru and Pinrang was 97-99%. BLAST-N (Basic Local Alignment Search Tool-Nucleotide) analysis showed isolates from all three sites clustered with WSSV VP28 accessions from China, Indonesia, Japan, South Carolina and Vietnam. These results increase the geographic spread and host taxon coverage of WSSV VP28 sequence data for Indonesia.

Isolation and evaluation the effect of Bacillus subtillis BLD01 strain on the survival rates and gut microbiota of Penaeus vannamei after challenge with Vibrio parahaemolyticus

Acute hepatopancreatic necrosis disease (AHPND) caused by Vibrio parahaemolyticus has caused severe damage to the shrimp farming industry of Vietnam. Probiotics are chosen as a prophylactic method to mitigate the outbreak of diseases. We report in this article the isolation and evaluation of the effect of a potential probiotic, Bacillus subtilis BLD01, which enhances the survival rates and changes gut microbiota of whiteleg shrimp (Penaeus vannamei) after challenge with AHPND V. parahaemolyticus. After seven days of the challenge, the treatment where shrimps were fed with B. subtilis BLD01 strain (106 CFU/g) and challenge with AHPND V. parahaemolyticus (106 CFU/mL) showed high survival rates of 71% as compared to 33% in the treatment where shrimp were given standard feed without probiotics supplementation and challenged with AHPND V. parahaemolyticus. 16S rRNA amplicon data of the gut microbiomes of shrimps in four treatments were carried out using Illumina sequencing. A total of 231 436 reads were obtained, and a total of 14 phyla, 28 classes, 142 genera were revealed. The most abundant phyla in all subjects were Proteobacteria and Bacteroidetes. The sequence number of the Vibrio genus was the highest with 28% in treatment without B. subtillis BLD01 in-feed addition and shrimps challenged with AHPND V. parahaemolyticus. The sequence number of Bacillus genus was the highest with 3% in the treatment with B. subtillis BLD01 addition and without AHPND V. parahaemolyticus challenge. These results contribute to confirming the mechanism of action of B. subtilis against V. parahaemolyticus in the experimental model, creating a scientific basis for the development and use of probiotics products applied in shrimp farming in Vietnam.

RNA-seq analysis revealing the immune response of Neocaridina denticulata sinensis gill to Vibrio parahaemolyticus infection

Vibrio parahaemolyticus causes serious economic losses to the shrimp farming industry. There is still a lack of adequate understanding of the changes in the overall response of N. denticulata sinensis caused by V. parahaemolyticus, particularly with respect to gill tissue, which is severely damaged by the pathogen. In this study, a total of 1358 differentially expressed genes were identified between the PBS control and Vibrio stimulation groups using transcriptome sequencing techniques. After further screening and analysis, many immune-related genes were obtained, involving lysosome pathway, metabolic process, chitin-binding protein, and serine protease family members. In addition, we randomly selected six DEGs in the lysosome pathway for qRT-PCR verification, and the results showed that their expression patterns were consistent with the RNA-seq. The results demonstrate the molecular regulation of the gill tissue response to V. parahaemolyticus infection in N. denticulata sinensis, contributing to the understand of the complex and efficient innate immune system and defense mechanisms in crustaceans.

Rapid visual detection of Enterocytozoon hepatopenaei by recombinase polymerase amplification combined with lateral flow dipstick

Enterocytozoon hepatopenaei (EHP) is a high-impact pathogen in shrimp farming, causing huge economic losses to the global shrimp farming industry every year. However, current EHP detection methods are primarily based on the development of polymerase chain reaction (PCR) techniques that rely on sophisticated and expensive instruments. Consequently, a rapid, practical, and sensitive protocol for the detection of EHP is necessary. Recombinase polymerase amplification combined with a lateral flow dipstick (LFD-RPA) assay was developed using a pair of primers and nfo-probe targeting the conserved region of the spore wall protein gene. Under optimized reaction conditions, the LFD-RPA assay can detect 10 copies/μL of standard plasmid within 20 min at 40°C. Furthermore, the specificity of the LFD-RPA was also verified with other common pathogens of shrimp. Thirty-nine samples of Litopenaeus vannamei were collected in shrimp farms and detected using LFD-RPA and nested PCR. Thirty-two positive samples were detected by LFD-RPA. Compared with those of nested PCR, the diagnostic sensitivity and specificity of LFD-RPA were 100% and 100%, respectively. These results indicated the great application potential of the newly developed LFD-RPA assay for point-of-care diagnosis, epidemic surveillance, and epidemiological investigation of EHP.

White Spot Syndrome Virus Triggers a Glycolytic Pathway in Shrimp Immune Cells (Hemocytes) to Benefit Its Replication.

White spot syndrome virus (WSSV) is the causative agent of a shrimp disease that inflicts in huge economic losses in shrimp-farming industry. WSSV triggers aerobic glycolysis in shrimp immune cells (hemocytes), but how this virus regulates glycolytic enzymes or pathway is yet to be characterized. Therefore, mRNA levels and activity of four important glycolytic enzymes, Hexokinase (HK), Phosphofructokinase (PFK), Pyruvate kinase (PK), and Lactate dehydrogenase (LDH), were measured in WSSV-infected shrimp hemocytes. Gene expression of HK and PFK, but not LDH or PK, was increased at the viral genome replication stage (12 hpi); furthermore, activity of these enzymes, except HK, was concurrently increased. However, there was no increased enzyme activity at the viral late stage (24 hpi). In vivo dsRNA silencing and glycolysis disruption by 2-DG further confirmed the role of glycolysis in virus replication. Based on tracing studies using stable isotope labeled glucose, glycolysis was activated at the viral genome replication stage, but not at the viral late stage. This study demonstrated that WSSV enhanced glycolysis by activating glycolytic enzyme at the viral genome replication stage, providing energy and biomolecules for virus replication.

Monoclonal antibodies (mAbs) and single chain variable fragment (scFv) antibodies targeting envelope protein VP28 of white spot syndrome virus provide protection against viral infection

White spot syndrome virus (WSSV) is extremely pathogenic and causes huge economic losses in the shrimp farming industry. Neutralizing antibodies against WSSV is expected to be an effective means of preventing infection with the virus. In the present study, eight monoclonal antibodies (mAbs) against VP28 were developed by immunizing BALB/c mice with WSSV-VP28 recombinant protein. Among them, three mAbs named 3B7, 2G3 and 5D2 were determined to be able to delay the mortality of WSSV-infected shrimp in vivo neutralization assay, suggesting their neutralizing ability against WSSV infection. Immunoblotting results showed that the three mAbs reacted specifically with native VP28 of WSSV, and could also recognize the virions in the gills of WSSV-infected shrimp by IFA. Furthermore, the single chain variable fragment (scFv) genes specific for WSSV-VP28 were cloned from the three hybridoma cells and expressed in Escherichia coli. After purification and refolding, three biologically active scFv recombinant proteins were all capable of recognizing the native VP28 of WSSV and delayed the mortality of WSSV-infected shrimp, indicating their neutralizing capacity against WSSV. Subsequently, the eukaryotic expression plasmids of three scFv genes were constructed and the transcriptional properties of expression vectors in shrimp were analyzed. Animal experiments also proved that the scFv eukaryotic expression plasmids were able to partially neutralize WSSV infection. Thus, the production of neutralizing mAb and recombinant scFv antibodies against WSSV has a promising therapeutic potential in prevention and treatment of white spot disease of shrimp.

Investigation of Pathogenic Mechanism of Covert Mortality Nodavirus Infection in Penaeus vannamei.

Viral covert mortality disease (VCMD), also known as running mortality syndrome (RMS), is caused by covert mortality nodavirus (CMNV) and has impacted the shrimp farming industry in Asia and Latin America in recent years. The pathogenic mechanism of CMNV infecting Penaeus vannamei was investigated in this study. In the naturally infected shrimp, histopathological and in situ hybridization (ISH) analysis verified that CMNV infection and severe cellar structural damage occurred in almost all cells of the ommatidium. Under transmission electron microscopic (TEM), vacuolation and necrosis, together with numerous CMNV-like particles, could be observed in the cytoplasm of most cell types of the ommatidium. The challenge test showed that a low CMNV infectious dose caused cumulative mortality of 66.7 ± 6.7% and 33.3 ± 3.6% of shrimp in the 31-day outdoor and indoor farming trials, respectively. The shrimp in the infection group grew slower than those in the control group; the percentage of soft-shell individuals in the infection group (42.9%) was much higher than that of the control group (17.1%). The histopathological and ISH examinations of individuals artificially infected with CMNV revealed that severe cellar damage, including vacuolation, karyopyknosis, and structural failure, occurred not only in the cells of the refraction part of the ommatidium, but also in the cells of the nerve enrichment and hormone secretion zones. And the pathological damages were severe in the nerve cells of both the ventral nerve cord and segmental nerve of the pleopods. TEM examination revealed the ultrastructural pathological changes and vast amounts of CMNV-like particles in the above-mentioned tissues. The differential transcriptome analysis showed that the CMNV infection resulted in the significant down-regulated expression of genes of photo-transduction, digestion, absorption, and growth hormones, which might be the reason for the slow growth of shrimp infected by CMNV. This study uncovered unique characteristics of neurotropism of CMNV for the first time and explored the pathogenesis of slow growth and shell softening of P. vannamei caused by CMNV infection.

Description of biosecurity practices on shrimp farms in Java, Lampung, and Banyuwangi, Indonesia

The sustainability of the Indonesian shrimp farming industry is challenged by the presence of bacterial and viral diseases and their associated potential for severe economic losses and environmental impact. In shrimp aquaculture, biosecurity is essential to prevent pathogen introduction, emergence and spread within and between farms. This study was undertaken (1) to design and implement a questionnaire survey addressing key shrimp aquaculture management and biosecurity practices, and (2) to provide an overview and patterns of the current state of biosecurity for grow-out and intensive shrimp farms in Indonesia. A questionnaire was designed to collect information on farm characteristics, farm management, and biosecurity practices. Descriptive statistics, multiple correspondence analyses, and hierarchical clustering were used to summarize and identify patterns of biosecurity practices implemented by farmers and to classify farms into different clusters, based on these practices. Three distinct clusters were identified for 96 grow-out farms in Java and Lampung area, while 7 clusters were identified for 101 intensive farms in Banyuwangi area. For Java and Lampung, 2 clusters were mostly characterized by micro and small-scale farms, with less intense biosecurity practices, including not testing seed quality, not disinfecting people, vehicles, or equipment, not removing dead animals. One cluster was best represented by medium and large-scale farms applying higher intensity biosecurity practices, including greater distance to neighboring farms, disinfection for visitors, vehicles, and staff, testing seed quality, and fallow period greater than 30 days between cycles. In Banyuwangi area, farms could not be distinctly classified into clusters by patterns of biosecurity practices but were defined more by farm management and characteristics of the data structure (e.g., lack of response or missing records). For future sustainable surveillance programs and biosecurity implementation to reduce the risk of disease introduction and spread in these regions, recommendations include: training for improved, transparent, and consistent record-keeping; focusing future data collection on cluster or region-specific priorities and disease-specific biosecurity approaches by farming method (e.g., for intensive vs. grow-out); and increasing evidence-based decisions using epidemiological knowledge developed within industry, government, and shrimp aquaculture farmers.

White spot syndrome virus host range and impact on transmission

AbstractWhite spot syndrome virus (WSSV), the etiological agent of white spot disease (WSD), is a significant pathogen affecting shrimp farming industry worldwide. White spot syndrome virus is a generalist virus mainly infecting decapod crustaceans. The aims of this review were to: (1) Re‐evaluate and update the status of reported WSSV host and vector species based on the methods used when detecting replication and transmission to shrimp and 2) make a critical evaluation of existing literature on the presence of WSSV in aquatic organisms and the potential role these organisms might play in the transmission of WSSV in pond systems and the wild. An evaluation of literature about WSSV reported host and vector species showed an increase from 33 families to 50 families including 11 families of non‐crustacean hosts, proved the virus continues to spread beyond farmed shrimp and the shrimp pond environment. White spot syndrome virus transmission in the aquatic environment is complex as depicted in our model. Containment of WSSV in ponds and the natural environment is challenging, mainly because of its generalist nature and a lack of understanding about (1) WSSV transmission in the aquatic setting, (2) the route of WSSV transmission among species exist in the aquatic environment and (3) information on the transmission dynamics between WSSV in farmed crustaceans and non‐farmed animals. Information presented in this review provides the research direction on methods to control WSSV.