Displaying publications 21 - 40 of 70 in total

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  1. Loc NH, Macrae TH, Musa N, Bin Abdullah MD, Abdul Wahid ME, Sung YY
    PLoS One, 2013;8(9):e73199.
    PMID: 24039886 DOI: 10.1371/journal.pone.0073199
    Non-lethal heat shock boosts bacterial and viral disease tolerance in shrimp, possibly due to increases in endogenous heat shock protein 70 (Hsp70) and/or immune proteins. To further understand the mechanisms protecting shrimp against infection, Hsp70 and the mRNAs encoding the immune-related proteins prophenoloxidase (proPO), peroxinectin, penaeidin, crustin and hemocyanin were studied in post-larvae of the white-leg shrimp Litopenaeus vannamei, following a non-lethal heat shock. As indicated by RT-qPCR, a 30 min abrupt heat shock increased Hsp70 mRNA in comparison to non-heated animals. Immunoprobing of western blots and quantification by ELISA revealed that Hsp70 production after heat shock was correlated with enhanced Hsp70 mRNA. proPO and hemocyanin mRNA levels were augmented, whereas peroxinectin and crustin mRNA levels were unchanged following non-lethal heat shock. Penaeidin mRNA was decreased by all heat shock treatments. Thirty min abrupt heat shock failed to improve survival of post-larvae in a standardized challenge test with Vibrio harveyi, indicating that under the conditions of this study, L. vannamei tolerance to Vibrio infection was influenced neither by Hsp70 accumulation nor the changes in the immune-related proteins, observations dissimilar to other shrimp species examined.
    Matched MeSH terms: Penaeidae/genetics*; Penaeidae/immunology; Penaeidae/microbiology*
  2. Anirudhan A, Okomoda VT, Mimi Iryani MT, Andriani Y, Abd Wahid ME, Tan MP, et al.
    Fish Shellfish Immunol, 2021 Feb;109:97-105.
    PMID: 33352338 DOI: 10.1016/j.fsi.2020.12.011
    Plants and herbal extracts are indispensable for controlling the spread of disease-causing bacteria, including those that infect aquatic organisms used in aquaculture. The use of plant or herbal extract is expected to be safe for aquatic animals and less harmful to the environment, as opposed to conventional therapeutic alternatives such as antibiotics that promote the occurrence of potential antibiotic-resistant bacteria when used improperly. The efficacy of Pandanus tectorius fruit extract in the regulation of Hsp70 expression, pro-phenoloxidase (ProPO), peroxinectin, penaeidin, crustin and transglutaminase, all immune peptides essential for Vibrio tolerance in white leg shrimp, Penaeus vannamei, was investigated in this study, which included the determination of the safety levels of the extract. Tolerance of shrimp against Vibrio parahaemolyticus, a pathogenic bacteria that causes Acute Hepatopancreas Necrosis Disease (AHPND), was assessed on the basis of median lethal dose challenge survival (LD50 = 106 cells/ml). Mortality was not observed 24 h after exposure of 0.5-6 g/L of the fruit extract, indicating that P. tectorius was not toxic to shrimp at these concentrations. A 24-h incubation of 2-6 g/L of the fruit extract increased shrimp tolerance to V. parahaemolyticus, with survival doubled when the maximum dose tested in this study was used. Concomitant with a rise in survival was the increase in immune-related proteins, with Hsp70, ProPO, peroxinectin, penaeidin, crustin and transglutaminase increased 10, 11, 11, 0.4, 8 and 13-fold respectively. Histological examination of the hepatopancreas and muscle tissues of Vibrio-infected shrimp primed with P. tectorius extract revealed reduced signs of histopathological degeneration, possibly due to the accumulation of Hsp70, a molecular chaperone crucial to cellular protein folding, tissue repair and immune response of living organisms, including Penaeid shrimp.
    Matched MeSH terms: Penaeidae/genetics; Penaeidae/immunology*; Penaeidae/microbiology
  3. Akazawa, Noriaki, Eguchi, Mitsuru
    MyJurnal
    Microcosm experiments simulating the occurrence of early mortality syndrome/acute hepatopancreatic necrosis disease (EMS/AHPND) in white shrimp production ponds were performed in 30-L aquariums. Healthy white shrimp, Litopenaeus vannamei, were reared in aquariums containing EMS/AHPND-free hatchery or pond water. Raw pond sludge, collected from shrimp ponds where EMS/AHPND had occurred, was added to some test aquariums, while others were treated with sterilized pond sludge. In some aquariums, water pH was increased from 7.5 to 8.8. Microcosms with stable pH (around 7.5) and/or autoclaved sludge served as controls. The combination of raw sludge and increased pH induced EMS/AHPND and killed white shrimp, whereas raw sludge/stable pH and autoclaved sludge/increased pH combinations did not affect healthy shrimp. Thus, EMS/AHPND outbreaks are due not only to the causative agent but also to environmental stresses such as pH fluctuation. These findings contribute to improved management in shrimp production farms.
    Matched MeSH terms: Penaeidae
  4. Sinnasamy S, Noordin NM, MacRae TH, Bin Abdullah MI, Bossier P, Wahid ME, et al.
    J Fish Dis, 2016 May;39(5):577-84.
    PMID: 26132358 DOI: 10.1111/jfd.12390
    Feeding aquatic animals with bacterial encapsulated heat-shock proteins (Hsps) is potentially a new method to combat vibriosis, an important disease affecting aquatic animals used in aquaculture. Food pellets comprised of shrimp and containing Escherichia coli overexpressing either DnaK-DnaJ-GrpE, the prokaryotic equivalents of Hsp70-Hsp40-Hsp20, or only DnaK were fed to juveniles of the white leg shrimp Penaeus vannamei, and protection against pathogenic Vibrio harveyi was determined. Maintaining pellets at different temperatures for varying lengths of time reduced the number of live adhering E. coli, as did contact with sea water, demonstrating that storage and immersion adversely affected bacterial survival and attachment to pellets. Feeding P. vannamei with E. coli did not compromise their survival, indicating that the bacteria were not pathogenic to shrimp. Feeding P. vannamei with pellets containing bacteria overproducing DnaK (approximately 60 cells g(-1) pellets) boosted P. vannamei survival twofold against V. harveyi, suggesting that DnaK plays a role in Vibrio tolerance. Pellets containing DnaK were effective in providing protection to P. vannamei for up to 2 weeks before loss of viability and that DnaK encapsulated by these bacteria enhanced shrimp resistance against Vibrio infection.
    Matched MeSH terms: Penaeidae/immunology; Penaeidae/microbiology*
  5. Sahtout AH, Hassan MD, Shariff M
    Dis Aquat Organ, 2001 Mar 9;44(2):155-9.
    PMID: 11324818
    Fifty black tiger shrimp Penaeus monodon from commercial cultivation ponds in Malaysia were examined by Tdt-mediated dUTP nick-end labeling (TUNEL) fluorescence assay and agarose gel electrophoresis of DNA extracts for evidence of DNA fragmentation as an indicator of apoptosis. From these specimens, 30 were grossly normal and 20 showed gross signs of white spot syndrome virus (WSSV) infection. Of the 30 grossly normal shrimp, 5 specimens were found to be positive for WSSV infection by normal histology and by nested polymerase chain reaction (PCR) analysis. All of the specimens showing gross signs of WSSV infection were positive for WSSV by normal histology, while 5 were positive by nested PCR only (indicating light infections) and 15 were positive by 1-step PCR (indicating heavy infections). Typical histological signs of WSSV infection included nuclear hypertrophy, chromatin condensation and margination. None of the 25 grossly normal shrimp negative for WSSV by 1-step PCR showed any signs of DNA fragmentation by TUNEL assay or agarose gel electrophoresis of DNA extracts. The 10 specimens that gave PCR-positive results for WSSV by nested PCR only (i.e., 5 grossly normal shrimp and 5 grossly positive for WSSV) gave mean counts of 16 +/- 8% TUNEL-positive cells, while the 25 specimens PCR positive by 1-step PCR gave mean counts of 40 +/- 7% TUNEL-positive cells. Thus, the number of TUNEL positive cells present in tissues increased with increasing severity of infection, as determined by gross signs of white spots on the cuticle, the number of intranuclear inclusions in histological sections, and results from single and nested PCR assays. DNA extracts of PCR-positive specimens tested by agarose gel electrophoresis showed indications of DNA fragmentation either as smears or as 200 bp ladders. Given that DNA fragmentation is generally considered to be a hallmark of apoptosis, the results suggested that apoptosis might be implicated in shrimp death caused by WSSV.
    Matched MeSH terms: Penaeidae/genetics*; Penaeidae/virology*
  6. Zhang X, Sun J, Chen F, Qi H, Chen L, Sung YY, et al.
    Microb Genom, 2021 05;7(5).
    PMID: 33952389 DOI: 10.1099/mgen.0.000549
    The virulence of Vibrio parahaemolyticus is variable depending on its virulence determinants. A V. parahaemolyticus strain, in which the virulence is governed by the pirA and pirB genes, can cause acute hepatopancreatic necrosis disease (AHPND) in shrimps. Some V. parahaemolyticus that are non-AHPND strains also cause shrimp diseases and result in huge economic losses, while their pathogenicity and pathogenesis remain unclear. In this study, a non-AHPND V. parahaemolyticus, TJA114, was isolated from diseased Penaeus vannamei associated with a high mortality. To understand its virulence and adaptation to the external environment, whole-genome sequencing of this isolate was conducted, and its phenotypic profiles including pathogenicity, growth characteristics and nutritional requirements were investigated. Shrimps following artificial infection with this isolate presented similar clinical symptoms to the naturally diseased ones and generated obvious pathological lesions. The growth characteristics indicated that the isolate TJA114 could grow well under different salinity (10-55 p.p.t.), temperature (23-37 °C) and pH (6-10) conditions. Phenotype MicroArray results showed that this isolate could utilize a variety of carbon sources, amino acids and a range of substrates to help itself adapt to the high hyperosmotic and alkaline environments. Antimicrobial-susceptibility test showed that it was a multidrug-resistant bacterium. The whole-genomic analysis showed that this V. parahaemolyticus possessed many important functional genes associated with multidrug resistance, stress response, adhesions, haemolysis, putative secreted proteases, dedicated protein secretion systems and a variety of nutritional metabolic mechanisms. These annotated functional genes were confirmed by the phenotypic profiles. The results in this study indicated that this V. parahaemolyticus isolate possesses a high pathogenicity and strong environmental adaptability.
    Matched MeSH terms: Penaeidae/genetics; Penaeidae/microbiology*
  7. Kasan NA, Ghazali NA, Ikhwanuddin M, Ibrahim Z
    Pak J Biol Sci, 2017;20(6):306-313.
    PMID: 29023055 DOI: 10.3923/pjbs.2017.306.313
    BACKGROUND AND OBJECTIVE: A new green technology to reduce environmental damages while optimizing production of Pacific Whiteleg shrimp, Litopenaeus vannamei was developed known as "Biofloc technology". Microbial communities in biofloc aggregates are responsible in eliminating water exchange and producing microbial proteins that can be used as supplemented feed for L. vannamei. This study aimed to isolate and identify potential bioflocculant-producing bacteria to be used as inoculum for rapid formation of biofloc.

    MATERIALS AND METHODS: For the purpose of this study, bacterial communities during 0, 30 and 70 days of culture (DOC) of L. vannamei grow-out ponds were isolated and identified through phenotypic and 16S rDNA sequences analysis. Phylogenetic relationships between isolated bacteria were then evaluated through phylogenetic tree analysis. One-way analysis of variance (ANOVA) was used to compare the differences of microbial communities at each DOC.

    RESULTS: Out of 125 bacterial isolates, nine species of bacteria from biofloc were identified successfully. Those bacteria species were identified as Halomonas venusta, H. aquamarina, Vibrio parahaemolyticus, Bacillus infantis, B. cereus, B. safensis, Providencia vermicola, Nitratireductor aquimarinus and Pseudoalteromonas sp., respectively. Through phylogenetic analysis, these isolates belong to Proteobacteria and Firmicutes families under the genera of Halomonas sp., Vibrio sp., Bacillus sp., Providencia sp., Nitratireductor sp. and Pseudoalteromonas sp.

    CONCLUSION: In this study, bioflocculant-producing bacteria were successfully identified which are perfect candidates in forming biofloc to reduce water pollution towards a sustainable aquaculture industry. Presence of Halomonas sp. and Bacillus sp. in all stages of biofloc formation reinforces the need for new development regarding the ability of these species to be used as inoculum in forming biofloc rapidly.

    Matched MeSH terms: Penaeidae/growth & development; Penaeidae/microbiology*
  8. Zokaeifar H, Balcázar JL, Saad CR, Kamarudin MS, Sijam K, Arshad A, et al.
    Fish Shellfish Immunol, 2012 Oct;33(4):683-9.
    PMID: 22659618 DOI: 10.1016/j.fsi.2012.05.027
    We studied the effect of two probiotic Bacillus subtilis strains on the growth performance, digestive enzyme activity, immune gene expression and disease resistance of juvenile white shrimp (Litopenaeus vannamei). A mixture of two probiotic strains, L10 and G1 in equal proportions, was administered at two different doses 10(5) (BM5) and 10(8) (BM8) CFU g(-1) feed to shrimp for eight weeks. In comparison to untreated control group, final weight, weight gain and digestive enzyme activity were significantly greater in shrimp fed BM5 and BM8 diets. Significant differences for specific growth rate (SGR) and survival were recorded in shrimp fed BM8 diet as compared with the control; however, no significant differences were recorded for food conversion ratio (FCR) among all the experimental groups. Eight weeks after the start of the feeding period, shrimp were challenged with Vibrio harveyi. Statistical analysis revealed significant differences in shrimp survival between probiotic and control groups. Cumulative mortality of the control group was 63.3%, whereas cumulative mortality of the shrimp that had been given probiotics was 20.0% with BM8 and 33.3% with BM5. Subsequently, real-time PCR was employed to determine the mRNA levels of prophenoloxidase (proPO), peroxinectin (PE), lipopolysaccharide- and β-1,3-glucan-binding protein (LGBP) and serine protein (SP). The expression of all immune-related genes studied was significantly up-regulated (P 
    Matched MeSH terms: Penaeidae/growth & development; Penaeidae/immunology; Penaeidae/metabolism; Penaeidae/microbiology*
  9. Soo TCC, Bhassu S
    PLoS One, 2021;16(10):e0258655.
    PMID: 34653229 DOI: 10.1371/journal.pone.0258655
    Diseases have remained the major issue for shrimp aquaculture industry for decades by which different shrimp species demonstrated alternative disease resistance or tolerance. However, there had been insufficient studies on the underlying host mechanisms of such phenomenon. Hence, in this study, the main objective involves gaining a deeper understanding into the functional importance of shrimp STAT gene from the aspects of expression, sequence, structure, and associated genes. STAT gene was selected primarily because of its vital signalling roles in stress, endocrine, and immune response. The differential gene expressions of Macrobrachium rosenbergii STAT (MrST) and Penaeus monodon STAT (PmST) under White Spot Syndrome Virus (WSSV) and Vibrio parahaemolyticus/VpAHPND infections were identified through qPCR analysis. Notably, during both pathogenic infections, MrST demonstrated significant gene expression down-regulations (during either early or later post-infection time points) whereas PmST showed only significant gene expression up-regulations. Important sequence conservation or divergence was highlighted through STAT sequence comparison especially amino acid alterations at 614 aa [K (Lysine) to E (Glutamic Acid)] and 629 aa [F (Phenylalanine) to V (Valine)] from PmST (AY327491.1) to PmST (disease tolerant strain). There were significant differences observed between in silico characterized structures of MrST and PmST proteins. Important functional differentially expressed genes (DEGs) in the aspects of stress, endocrine, immune, signalling, and structural were uncovered through comparative transcriptomic analysis. The DEGs associated with STAT functioning were identified including inositol 1,4,5-trisphosphate receptor, hsp90, caspase, ATP binding cassette transmembrane transporter, C-type Lectin, HMGB, ALF1, ALF3, superoxide dismutase, glutathione peroxidase, catalase, and TBK1. The main findings of this study are STAT differential gene expression patterns, sequence divergence, structural differences, and associated functional DEGs. These findings can be further utilized for shrimp health or host response diagnostic studies. STAT gene can also be proposed as a suitable candidate for future studies of shrimp innate immune enhancement.
    Matched MeSH terms: Penaeidae/genetics*; Penaeidae/virology
  10. Wen, Chiat Lee, Lim, Siak Ze, K. Kuperan Viswanathan, Md Ariful Islam
    MyJurnal
    Shrimp aquaculture has great potential for providing income and employment opportunities to farmers. Shrimp production can also contribute to economic growth given its high value and demand in Malaysia. However, it is often said that players in the marketing channel extract high margins for themselves. This study intends to verify this claim by examining a case study based on white leg shrimp (Litopenaeus vannamei) aquaculture in Kedah. The data for this study was obtained from a detailed study involving a shrimp retailer in Kedah. The marketing margins were calculated from the interviews of the farmer and the retailer. The results showed that the marketing channel was quite efficient because there was no large gap in the prices between the marketing channels. The difference between retail price and farm price is only RM7 per kilogram for the white shrimp which accounts for 43.75 percent of total farm price and represents the cost of bringing shrimps from the farm to the retail market.
    Matched MeSH terms: Penaeidae
  11. Devadas S, Bhassu S, Christie Soo TC, Mohamed Iqbal SN, Yusoff FM, Shariff M
    Microbiol Resour Announc, 2018 Jul;7(2).
    PMID: 30533806 DOI: 10.1128/MRA.00829-18
    We report the first draft genome sequence of a Vibrio parahaemolyticus strain (VpAHPND), which causes acute hepatopancreatic necrosis disease (AHPND) in Penaeus monodon. The strain has a pVA1-like plasmid carrying pirAvp and pirBvp genes. Whole-genome comparisons revealed >98% similarity to VpAHPND isolates from Thailand, Mexico, and Vietnam.
    Matched MeSH terms: Penaeidae
  12. Devadas S, Bhassu S, Christie Soo TC, Yusoff FM, Shariff M
    Microbiol Resour Announc, 2018 Sep;7(11).
    PMID: 30533648 DOI: 10.1128/MRA.01053-18
    We sequenced the genome of Vibrio parahaemolyticus strain ST17.P5-S1, isolated from Penaeus vannamei cultured in the east coast of Peninsular Malaysia. The strain contains several antibiotic resistance genes and a plasmid encoding the Photorhabdus insect-related (Pir) toxin-like genes, pirAvp and pirBvp, associated with acute hepatopancreatic necrosis disease (AHPND).
    Matched MeSH terms: Penaeidae
  13. Ghee-Thean, L., Islam, G.M.N., Ismail, M.M.
    MyJurnal
    Shrimp aquaculture is playing a vital role in Malaysian agriculture, especially its increasing
    contribution to economic growth. White shrimp aquaculture is not only the key player in brackish
    water shrimp aquaculture but also the largest contributor to Malaysian shrimp aquaculture. This
    study estimates technical efficiency and investigates factors affecting technical inefficiency of
    Malaysian white shrimp aquaculture. Stochastic frontier analysis with trans-log production
    model is applied in this study. Malaysian white shrimp aquaculture farmers have achieved
    an estimated average technical efficiency of 81.2 percent. Land ownership, shrimp seed size
    and seminar are the factors having significant impacts on technical inefficiency and thereby
    playing important roles in improving technical efficiency of this industry. This study suggests
    that seminar should be conducted by shrimp farming extension agents to enhance knowledge
    of shrimp farmers. Malaysian government should allocate lands and, provide technical and
    financial supports to develop this industry. Subsidy on shrimp seed should be also given to
    encourage shrimp farmers to embrace and adopt quality shrimp seed for their farms.
    Matched MeSH terms: Penaeidae
  14. Jiang B, Sun J, Lv A, Hu X, Shi H, Sung Y, et al.
    FEMS Microbiol Lett, 2019 05 01;366(9).
    PMID: 31074797 DOI: 10.1093/femsle/fnz099
    Two DNA extraction methods, the Zirmil-beating cell disruption method (ZBC) and the QIAamp fast DNA stool mini kit (QIA), were used to extract DNA from the intestinal flora of the penaeid shrimp Litopenaeus vannamei, and their microbial communities were analyzed using 16S rDNA high-throughput sequencing. Results were obtained in terms of the number of reads, alpha diversity indexes, beta diversity indexes and taxonomic composition. The alpha diversity indexes of the community, according to the ZBC method, were higher than those according to the QIA method. Furthermore, results from the three samples using the ZBC method were less consistent than those where the QIA method was used. Further, using the latter method led to substantive clustering. It is suggested that the QIA method is more stable and repeatable than the ZBC method. Although the two extraction methods shared the major abundant microflora based on 16S rDNA high-throughput sequencing, bias associated with diversity analysis indexes and certain species was observed.
    Matched MeSH terms: Penaeidae
  15. Jamizan A, Chong V
    Sains Malaysiana, 2017;46:9-19.
    Previous studies have found positive correlations between mangrove forest extent and fisheries yield but none of these univariate relationships provide a reliable estimate of yield from mangrove area. This study tests the hypothesis that the nursery ground value or natural production of fish and shrimps is related to the hydrogeomorphology settings of mangrove forests by using multivariate redundancy analysis (RDA). The hydrogeomorphological metrics of five mangrove forests imaged by satellite were measured using Geographical Information System (GIS). The RDA indicated that the metrics, including mangrove area, multiple waterways and creeks, mangrove-river interface, waterway surface area and sediment organic matter, influenced the diversity and abundance of fish and shrimps. Larger values of these metrics increase the abundance of economically important fish species of the families Lutjanidae, Haemulidae, Serranidae and economically-important penaeid shrimps. Sediment organic matter also significantly correlates with the distribution and abundance of fish that feed off the bottom such as the Leiognathidae, Clupeidae and Mullidae. Mangrove forests with combinations of large mangrove area, river surface area, high stream ordering and longest mangrove-river interface will provide greater role as nursery grounds for fish and shrimps.
    Matched MeSH terms: Penaeidae
  16. Sarkar T, Alam MM, Parvin N, Fardous Z, Chowdhury AZ, Hossain S, et al.
    Toxicol Rep, 2016;3:346-350.
    PMID: 28959555 DOI: 10.1016/j.toxrep.2016.03.003
    This study is aimed to assess the heavy metals contamination and health risk in Shrimp (Macrobrachium rosenbergii and Penaeus monodon) collected from Khulna-Satkhira region in Bangladesh. The results showed that the Pb concentrations (0.52-1.16 mg/kg) in all shrimp samples of farms were higher than the recommended limit. The Cd levels (0.05-0.13 mg/kg) in all samples and Cr levels in all farms except tissue content at Satkhira farm were higher than the permissible limits. The individual concentration of Pb, Cd, and Cr between shrimp tissue and shell in all rivers and farms were not statistically significant (P > 0.05). Target hazard quotient (THQ) and hazard index (HI) were estimated to assess the non-carcinogenic health risks. Shrimp samples from all locations under the current study were found to be safe for consumption, the possibility of health risk associated with non-carcinogenic effect is very low for continuous consumption for 30 years.
    Matched MeSH terms: Penaeidae
  17. Radzali SA, Baharin BS, Othman R, Markom M, Rahman RA
    J Oleo Sci, 2014;63(8):769-77.
    PMID: 25007745
    In recent years, astaxanthin is claimed to have a 10 times higher antioxidant activity than that of other carotenoids such as lutein, zeaxanthin, canthaxanthin, and β-carotene; the antioxidant activity of astaxanthin is 100 times higher than that of α-tocopherol. Penaeus monodon (tiger shrimp) is the largest commercially available shrimp species and its waste is a rich source of carotenoids such as astaxanthin and its esters. The efficient and environment-friendly recovery of astaxanthins was accomplished by using a supercritical fluid extraction (SFE) technique. The effects of different co-solvents and their concentrations on the yield and composition of the extract were investigated. The following co-solvents were studied prior to the optimization of the SFE technique: ethanol, water, methanol, 50% (v/v) ethanol in water, 50% (v/v) methanol in water, 70% (v/v) ethanol in water, and 70% (v/v) methanol in water. The ethanol extract produced the highest carotenoid yield (84.02 ± 0.8 μg/g) dry weight (DW) with 97.1% recovery. The ethanol extract also produced the highest amount of the extracted astaxanthin complex (58.03 ± 0.1 μg/g DW) and the free astaxanthin content (12.25 ± 0.9 μg/g DW) in the extract. Lutein and β-carotene were the other carotenoids identified. Therefore, ethanol was chosen for further optimization studies.
    Matched MeSH terms: Penaeidae/chemistry*
  18. Ong PT, Yong JC, Chin KY, Hii YS
    Chemosphere, 2011 Jul;84(5):578-84.
    PMID: 21529890 DOI: 10.1016/j.chemosphere.2011.03.059
    Understanding on the bioaccumulation and depuration of PAHs (polycyclic aromatic hydrocarbons) in Penaeus monodon is important in seafood safety because it is one of the most popular seafood consumed worldwide. In this study, we used anthracene as the precursor compound for PAHs accumulation and depuration in the shrimp. Commercial feed pellets spiked with anthracene were fed to P. monodon. At 20 mg kg(-1) anthracene, P. monodon accumulated 0.1% of the anthracene from the feed. P. monodon deputed the PAH two times faster than its accumulation. The shrimp reduced its feed consumption when anthracene content in the feed exceeded 20 mg kg(-1). At 100 mg kg(-1) anthracene, P. monodon started to have necrosis tissues on the posterior end of their thorax. The bioaccumulation factor (BAF), uptake rate constant (k(1)) and depuration rate constant (k(2)) of anthracene in P. monodon were 1.15×10(-3), 6.80×10(-4) d(-1) and 6.28×10(-1) d(-1), respectively. The depuration rate constant is about thousand times higher than the uptake rate constant and this indicated that this crustacean is efficient in depurating hydrocarbons from their tissue.
    Matched MeSH terms: Penaeidae/metabolism*
  19. Huys G, Bartie K, Cnockaert M, Hoang Oanh DT, Phuong NT, Somsiri T, et al.
    Res. Microbiol., 2007 Apr;158(3):228-35.
    PMID: 17350231
    In the present study, samples of pond water, sediment and farmed species were collected at 12 fish and shrimp farms in Malaysia, Thailand and Vietnam to determine the biodiversity and environmental distribution of chloramphenicol-resistant (CmR) mesophilic heterotrophs in Southeast Asian aquaculture sites. Following isolation on Iso-Sensitest agar supplemented with 35mug ml(-1) Cm and dereplication using (GTG)(5)-PCR fingerprinting, 557 genotypically unique CmR strains were subjected to polyphasic identification. The 557 mesophilic heterotrophic CmR isolates represented 18 different genera largely dominated by the genera Escherichia (40.2%), Pseudomonas (11.7%), Acinetobacter (11.1%), Klebsiella (7.5%) and Bacillus (5.9%). A total of 439 CmR isolates were further assigned to 31 described species or species groups, mainly including organisms that have been associated with various human opportunistic infections such as Escherichia coli (n=219), Pseudomonas putida (n=47), Klebsiella pneumoniae (n=38) and Acinetobacter baumannii (n=23). Strains of Escherichia, and most notably, of E. coli, were the only common group of CmR heterotrophs irrespective of country, sample type or farm type. Together with other predominant but less widespread groups such as acinetobacters and pseudomonads, the results of this biodiversity study suggest that E. coli can be regarded as a potential indicator of Cm resistance in Southeast Asian aquaculture environments.
    Matched MeSH terms: Penaeidae/microbiology
  20. Tang KF, Lightner DV
    Dis Aquat Organ, 2011 Feb 22;93(3):191-8.
    PMID: 21516971 DOI: 10.3354/dao02293
    We describe a duplex real-time PCR assay using TaqMan probes for the simultaneous detection of monodon baculovirus (MBV) and hepatopancreatic parvovirus (HPV). Both MBV and HPV are shrimp enteric viruses that infect intestinal and hepatopancreatic epithelial cells. Both viruses can cause significant mortalities and depressed growth in infected larval, postlarval, and early juvenile stages of shrimp, and thus present a risk to commercial aquaculture. In this duplex assay, we combined 2 single real-time PCRs, amplifying MBV and HPV, in a one-tube PCR reaction. The 2 viruses were distinguished by specific fluorescent labels at the 5' end of TaqMan probes: the MBV probe was labeled with dichlorodimethoxyfluorescein (JOE), and the HPV probe was labeled with 6-carboxyfluorescein (FAM). The duplex real-time PCR assay was performed in a multi-channel real-time PCR detection system, and MBV and HPV amplification signals were separately detected by the JOE and FAM channels. This duplex assay was validated to be specific to the target viruses and found to have a detection limit of single copies for each virus. The dynamic range was found to be from 1 to 1 x 10(8) copies per reaction. This assay was further applied to quantify MBV and HPV in samples of infected Penaeus monodon collected from Malaysia, Indonesia, and Thailand. The specificity and sensitivity of this duplex real-time PCR assay offer a valuable tool for routine diagnosis and quantification of MBV and HPV from both wild and farmed shrimp stocks.
    Matched MeSH terms: Penaeidae/virology*
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