Science.gov

Sample records for pangasius hypophthaimos pangasiidae

  1. Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: III. Five new species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius bocourti, P. djambal and P. hypophthalmus.

    PubMed

    Pariselle, A; Lim, L H S; Lambert, A

    2002-09-01

    The examination of gill parasites from Pangasius bocourti Sauvage, 1880; P. djambal Bleeker, 1846; P. hypophthalmus (Sauvage, 1878) and P. gigas Chevey, 1930 (Siluriformes, Pangasiidae) revealed the presence of seven species of Monogenea among which five are considered new species. They all belong to Thaparocleidus Jain, 1952 (Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001). P. bocourti: T. combesi n. sp., T. komarudini n. sp. and T. vietnamensis n. sp. P. djambal: T. caecus (Mizelle & Kritsky, 1969), T. combesi n. sp., T. euzeti n. sp., T. komarudini n. sp. and T. sadilii n. sp. P. hypophthalmus: T. caecus, T. siamensis (Lim, 1990) and T. vietnamensis n. sp. P. gigas: no Monogenea were found on this host species. PMID:12375363

  2. Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: IX. Two new species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius mahakamensis.

    PubMed

    Pariselle, A; Lim, L H S; Lambert, A

    2005-12-01

    The examination of gill parasites from P. mahakamensis Pouyaud, Gustiano & Teugels, 2002 (Siluriformes, Pangasiidae) in Southeast Asia revealed the presence of three species of Monogenea. One (Thaparocleidus caecus (Mizelle & Kritsky, 1969)) had been previously described. The other two, belonging to Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001), are considered new species: T. pouyaudi n. sp. and T. teugelsi n. sp. PMID:16402564

  3. Optimization and physical properties of gelatin extracted from pangasius catfish (Pangasius sutchi) bone.

    PubMed

    Mahmoodani, F; Ardekani, V Sanaei; See, S F; Yusop, S M; Babji, A S

    2014-11-01

    In the present study, to establish the optimum gelatin extraction conditions from pangasius catfish (Pangasius sutchi) bone, Response Surface Methodology (RSM) with a 4-factor, 5-level Central Composite Design (CCD) was conducted. The model equation was proposed with regard to the effects of HCl concentration (%, X1), treatment time (h, X2), extraction temperature (°C, X3) and extraction time (h, X4) as independent variables on the hydroxyproline recovery (%, Y) as dependent variable. X 1 = 2.74 %, X 2 = 21.15 h, X 3 = 74.73 °C and X 4 = 5.26 h were found to be the optimum conditions to obtain the highest hydroxyproline recovery (68.75 %). The properties of optimized catfish bone gelatin were characterized by amino acid analysis, SDS-PAGE, gel strength, TPA and viscosity in comparison to bovine skin gelatin. The result of SDS-PAGE revealed that pangasius catfish bone gelatin consisted of at least 2 different polypeptides (α1 and α2 chains) and their cross-linked chains. Moreover, the pangasius catfish bone gelatin was found to contain 17.37 (g/100 g) imino acids (proline and hydroxyproline). Pangasius catfish bone gelatin also indicated physical properties comparable with that of bovine and higher than those from cold water fish gelatin. Based on the results of the present study, there is a potential for exploitation of pangasius catfish bone for gelatin production. Furthermore, RSM provided the best method for optimizing the gelatin extraction parameters. PMID:26396302

  4. ACE inhibitory activity of pangasius catfish (Pangasius sutchi) skin and bone gelatin hydrolysate.

    PubMed

    Mahmoodani, Fatemeh; Ghassem, Masomeh; Babji, Abdul Salam; Yusop, Salma Mohamad; Khosrokhavar, Roya

    2014-09-01

    Skin and bone gelatins of pangasius catfish (Pangasius sutchi) were hydrolyzed with alcalase to isolate Angiotensin Converting Enzyme (ACE) inhibitory peptides. Samples with the highest degree of hydrolysis (DH) were separated into different fractions with molecular weight cut-off (MWCO) sizes of 10, 3 and 1 kDa, respectively and assayed for ACE inhibitory activity. Skin and bone gelatins had highest DH of 64.87 and 68.48 % after 2 and 1 h incubation, respectively. Results from this study indicated that by decreasing the molecular weight of fractions, ACE inhibitory activity was increased. Therefore, F3 permeates (MWCO < 1 kDa) of skin (IC50 = 3.2 μg/ml) and bone (IC50 = 1.3 μg/ml) gelatins possessed higher ACE inhibitory activity compared to their untreated gelatins and corresponding hydrolyzed fractions. In this study, the major amino acids were Glycine followed by Proline with an increased amount of hydrophobic amino acid content in F3 permeates of skin (4.01 %) and bone (5.79 %) gelatin. Digestion stability against gastrointestinal proteases did not show any remarkable change on ACE inhibition potency of these permeates. It was concluded that alcalase hydrolysis of P. sutchi by-products could be utilized as a part of functional food or ingredients of a formulated drug in order to control high blood pressure. PMID:25190839

  5. Genetic divergence in wild population of endangered yellowtail catfish Pangasius pangasius (Hamilton-Buchanan, 1822) revealed by mtDNA.

    PubMed

    Mohindra, Vindhya; Singh, Rajeev K; Kumar, Rajesh; Sah, R S; Lal, Kuldeep K

    2015-04-01

    Pangasius pangasius, an endangered freshwater fish species, is an important component of capture fishery from Indian rivers. Samples collected through commercial catches from three riverine populations were analyzed with cytb (307 bp) and ATPase6&8 (842 bp) regions for population variation and differentiation. The sequences of the both the mitochondrial regions revealed high haplotype and low nucleotide diversity. Shallow genetic diversity based on ATPase6&8 was observed, however its haplotypes network clearly indicated two distinct mitochondrial lineages. Mismatch distribution suggested population bottlenecks followed by expansion in Mahanadi population. The present study indicated the ATPase6&8 to be a potential mitochondrial marker for studying the population sub-structuring in the wild population of P. pangasius. PMID:24409876

  6. Halogenated contaminants in farmed salmon, trout, tilapia, pangasius, and shrimp.

    PubMed

    van Leeuwen, S P J; van Velzen, M J M; Swart, C P; van der Veen, I; Traag, W A; de Boer, J

    2009-06-01

    Polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzo-p-furans (PCDD/Fs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane diastereomers (HBCDs), and perfluorinated compounds (PFCs) were analyzed in popular farmed fish such as salmon, trout, tilapia, and pangasius and in farmed shrimp. The samples originated from southeast Asia, Europe, and South America. Results show the following: (i) Carnivorous species contained higher contaminant concentrations than omnivorous species. (ii) Contaminant concentrations generally decreased per species in the following order of salmon > trout > tilapia approximately equal to pangasius approximately equal to shrimp. (iii) Most contaminant concentrations decreased in the following order of PCBs approximately equal to dichloro-diphenyl-trichloroethanes (DDTs) > hexachlorobenzene approximately equal to pentachlorobenzene approximately equal to dieldrin approximately equal to PBDEs approximately equal to alpha-HBCD approximately equal to perfluorooctane sulfonate (PFOS) > World Health Organization toxic equivalents (WHO-TEQ) [PCDD/Fs and dioxin-like (dl)-PCBs]. (iv) Contaminant concentrations were very low (mostly <1 ng/g wet weight) and far below the European and Dutch legislative limits. (v) Contaminant concentrations in farmed shrimp, pangasius, and tilapia were lower than those in wild fish, whereas contaminant concentrations in farmed salmon and trout were higher than those in lean wild marine fish. From the five species investigated, salmon is predominantly responsible (97%) for human exposure to the sum of the investigated contaminants. The contribution of trout, tilapia, pangasius, and shrimp is small (3%) because contaminant concentrations and consumption volumes were much lower. PMID:19569323

  7. Decontamination of Pangasius fish (Pangasius hypophthalmus) with chlorine or peracetic acid in the laboratory and in a Vietnamese processing company.

    PubMed

    Tong Thi, Anh Ngoc; Sampers, Imca; Van Haute, Sam; Samapundo, Simbarashe; Ly Nguyen, Binh; Heyndrickx, Marc; Devlieghere, Frank

    2015-09-01

    This study evaluated the decontamination of Pangasius fillets in chlorine or peracetic acid treated wash water. First, the decontamination efficacy of the washing step with chlorinated water applied by a Vietnamese processing company during trimming of Pangasius fillets was evaluated and used as the basis for the experiments performed on a laboratory scale. As chlorine was only added at the beginning of the batch and used continuously without renewal for 239min; a rapid increase of the bacterial counts and a fast decrease of chlorine in the wash water were found. This could be explained by the rapid accumulation of organic matter (ca. 400mg O2/L of COD after only 24min). Secondly, for the experiments performed on a laboratory scale, a single batch approach (one batch of wash water for treating a fillet) was used. Chlorine and PAA were evaluated at 10, 20, 50 and 150ppm at contact times of 10, 20 and 240s. Washing with chlorine and PAA wash water resulted in a reduction of Escherichia coli on Pangasius fish which ranged from 0-1.0 and 0.4-1.4logCFU/g, respectively while less to no reduction of total psychrotrophic counts, lactic acid bacteria and coliforms on Pangasius fish was observed. However, in comparison to PAA, chlorine was lost rapidly. As an example, 53-83% of chlorine and 15-17% of PAA were lost after washing for 40s (COD=238.2±66.3mg O2/L). Peracetic acid can therefore be an alternative sanitizer. However, its higher cost will have to be taken into consideration. Where (cheaper) chlorine is used, the processors have to pay close attention to the residual chlorine level, pH and COD level during treatment for optimal efficacy. PMID:26058007

  8. The chemical quality of frozen Vietnamese Pangasius hypophthalmus fillets.

    PubMed

    Guimarães, Carlos Frederico Marques; Mársico, Eliane Teixeira; Monteiro, Maria Lúcia Guerra; Lemos, Môsar; Mano, Sergio Borges; Conte Junior, Carlos Adam

    2016-05-01

    The aim of the present study was to evaluate the chemical quality parameters regarding frozen Pangasius hypophthalmus specimens from Vietnam. The proximate composition, pH, ammonia, biogenic amines (BAs), total mercury (Hg), malondialdehyde (MDA), and polyphosphate were determined. The moisture, protein, lipid and ash values were between 83.83-85.59, 12.51-14.52, 1.09-1.65, and 0.76-2.38 g 100 g(-1), respectively. Fraud by excessive polyphosphate addition was detected in 30% of the samples whereas Hg above the recommended limit was observed in 50% of the samples. With regard to compounds from the degradation process, low concentrations of individual BAs and pH values were found in this study and ranged from 5.88 to 6.18, except for samples with polyphosphate >1 g 100(-1) (pH > 7.00) were observed in the present study. However, ammonia concentration indicated that a degradation process initiated in 80% of the samples (0.12-0.34 NH 3 g(-1)) and 20% of the samples (1.87-1.94 μg NH 3 g(-1)) were in an advanced deterioration process. Furthermore, MDA values (1.21-7.88 mg kg(-1)) suggested some failures, mainly during transportation and/or storage. We concluded that quality control measures must be implemented on the Pangasius production chain to improve the quality of products provided to consumers worldwide. PMID:27247770

  9. Microbial ecology of Vietnamese Tra fish (Pangasius hypophthalmus) fillets during processing.

    PubMed

    Tong Thi, Anh Ngoc; Noseda, Bert; Samapundo, Simbarashe; Nguyen, Binh Ly; Broekaert, Katrien; Rasschaert, Geertrui; Heyndrickx, Marc; Devlieghere, Frank

    2013-10-15

    There are numerous factors that can have an impact on the microbial ecology and quality of frozen Pangasius hypophthalmus fillets during processing in Vietnam. The presence of spoilage bacteria along the processing line can shorten the shelf-life of thawed frozen fish products. Therefore, the spoilage microbiota throughout the processing chain of two companies (BC: large scale factory, chlorine-based process, BW: large scale factory, water-based process and SC: small scale factory, chlorine-based process) was identified by culture-dependent techniques and 16S rRNA gene sequencing. The microbiological counts were observed to be insignificantly different (p>0.05) between BC and BW. Surprisingly, chlorine treated fillets from the SC line were revealed to have significantly higher microbial counts than potable water treated fillets at BW line. This was determined to be a result of temperature abuse during processing at SC, with temperatures even greater than 10 °C being recorded from skinning onwards. On the contrary, the microbiota related to spoilage for BC and BW lines was determined by 16S rRNA gene sequencing to be more diverse than that on the SC line. A total of 174 isolates, 20 genera and 38 species were identified along the processing chains. The genera Aeromonas, Acinetobacter, Lactococcus and Enterococcus were prevalent at various processing steps on all the processing lines evaluated. A diverse range of isolates belonging to the Enterobacteriaceae such as Providencia, Shigella, Klebsiella, Enterobacter and Wautersiella were isolated from fillets sampled on the SC line whereas Serratia was only observed on fillets sampled on the BC and BW lines. The results can be used to improve Good Manufacturing Practices for processed Pangasius fillets and to select effective measures to prolong the shelf-life of thawed Vietnamese Pangasius fillets products. PMID:24140808

  10. Ecological risk assessment of the antibiotic enrofloxacin applied to Pangasius catfish farms in the Mekong Delta, Vietnam.

    PubMed

    Andrieu, Margot; Rico, Andreu; Phu, Tran Minh; Huong, Do Thi Thanh; Phuong, Nguyen Thanh; Van den Brink, Paul J

    2015-01-01

    Antibiotics applied in aquaculture production may be released into the environment and contribute to the deterioration of surrounding aquatic ecosystems. In the present study, we assessed the ecological risks posed by the use of the antibiotic enrofloxacin (ENR), and its main metabolite ciprofloxacin (CIP), in a Pangasius catfish farm in the Mekong Delta region, Vietnam. Water and sediment samples were collected in a stream receiving effluents from a Pangasius catfish farm that had applied ENR. The toxicity of ENR and CIP was assessed on three tropical aquatic species: the green-algae Chlorella sp. (72 h - growth inhibition test), the micro-invertebrate Moina macrocopa (48 h - immobilization test), and the Nile tilapia (Oreochromis niloticus). The toxic effects on O. niloticus were evaluated by measuring the cholinesterase (ChE) and catalase (CAT) activities in the fish brain and muscles, respectively, and by considering feed exposure and water exposure separately. Ecological risks were assessed by comparing maximum exposure concentrations with predicted no effect concentrations for cyanobacteria, green algae, invertebrates and fish derived with available toxicity data. The results of this study showed that maximum antibiotic concentrations in Pangasius catfish farm effluents were 0.68 μg L(-1) for ENR and 0.25 μg L(-1) for CIP (dissolved water concentrations). Antibiotics accumulated in sediments down-stream the effluent discharge point at concentrations up to 2590 μg kg(-1) d.w. and 592 μg kg(-1) d.w. for ENR and CIP, respectively. The calculated EC50 values for ENR and CIP were 111000 and 23000 μg L(-1) for Chlorella sp., and 69000 and 71000 μg L(-1) for M. macrocopa, respectively. Significant effects on the ChE and CAT enzymatic activities of O. niloticus were observed at 5 g kg(-1) feed and 400-50000 μg L(-1), for both antibiotics. The results of the ecological risk assessment performed in this study indicated only minor risks for cyanobacteria

  11. Effect of chitosan on shelf life of restructured fish products from pangasius (pangasianodon hypophthalmus) surimi during chilled storage.

    PubMed

    Jeyakumari A; George Ninan; Joshy C G; Parvathy U; Zynudheen A A; Lalitha K V

    2016-04-01

    In the present study, restructured products were prepared from pangasius surimi and their qualities were analysed under chilled storage. Pangasius surimi had 75.82 % moisture, 16.91 % protein, 2.76 % fat and 0.95 % ash. Restructured products were prepared in three different formulations by incorporating corn starch (10 %) and chitosan (0.75 %). Formulation containing only corn starch (10 %) was served as control. In all the formulations, mono unsaturated fatty acids were higher (45.14 %). The total volatile base nitrogen (TVB-N) showed an increasing trend and it was found to be higher in control (4.8 mg/100 g) on 10(th) day than the chitosan incorporated sample (3.5-4.2 mg/100 g) on 17(th) day during chill storage. Similarly, peroxide value (PV) was found to higher (8.85 milliequivalent of O2/kg) in control than the chitosan incorporated sample (4.5-6.8 milliequivalent of O2/kg) on 10(th) day. All the three formulations had an acceptable level of thiobarbituric acid (TBA) value that ranged between 0.023-0.098 mg of malanoldehyde/kg during chilled storage. Based on the sensory and microbiological analysis, products prepared without chitosan had a shelf life of 10 day whereas, products incorporated with chitosan had an extended shelf life of 17 day. PMID:27413240

  12. Monitoring and determination of sulfonamide antibiotics (sulfamethoxydiazine, sulfamethazine, sulfamethoxazole and sulfadiazine) in imported Pangasius catfish products in Thailand using liquid chromatography coupled with tandem mass spectrometry.

    PubMed

    Jansomboon, Worawat; Boontanon, Suwanna Kitpati; Boontanon, Narin; Polprasert, Chongrak; Thi Da, Chau

    2016-12-01

    This research aimed to monitor the concentrations of sulfamethoxydiazine (SMD), sulfamethazine (SMT), sulfamethoxazole (SMX) and sulfadiazine (SDZ) in imported Pangasius catfish products in Thailand. The residues of the four sulfonamides (SAs) were analyzed by extraction process and liquid chromatography coupled with tandem mass spectrometry. The highest concentrations found were 10.97ng/g for SMD, 6.23ng/g for SMT, 11.13ng/g for SDZ and 245.91ng/g for SMX, which was higher than the European Union (EU) standard (100ng/g). Moreover, all samples contaminated with SMX also contained SMT, indicating that more than one antibiotic was used for production in the country of origin. Because Thai standards for antibiotics in food have not been completely set, all contaminated discovered would not be considered to be an illegal food, in which antibiotic residues may affect human health in the long term. Therefore, antibiotic residues in Pangasius catfish products should be continually regulated and monitored. PMID:27374578

  13. GFP tagged Vibrio parahaemolyticus Dahv2 infection and the protective effects of the probiotic Bacillus licheniformis Dahb1 on the growth, immune and antioxidant responses in Pangasius hypophthalmus.

    PubMed

    Gobi, Narayanan; Malaikozhundan, Balasubramanian; Sekar, Vijayakumar; Shanthi, Sathappan; Vaseeharan, Baskaralingam; Jayakumar, Rengarajan; Khudus Nazar, Abdul

    2016-05-01

    In this study, the pathogenicity of GFP tagged Vibrio parahaemolyticus Dahv2 and the protective effect of the probiotic strain, Bacillus licheniformis Dahb1was studied on the Asian catfish, Pangasius hypophthalmus. The experiment was carried out for 24 days with three groups and one group served as the control (without treatment). In the first group, P. hypophthalmus was orally infected with 1 mL of GFP tagged V. parahaemolyticus Dahv2 at two different doses (10(5) and 10(7) cfu mL(-1)). In the second group, P. hypophthalmus was orally administrated with 1 ml of the probiotic B. licheniformis Dahb1 at two different doses (10(5) and 10(7) cfu mL(-1)). In the third group, P. hypophthalmus was orally infected first with 1 mL of GFP tagged V. parahaemolyticus Dahv2 followed by the administration of 1 mL of B. licheniformis Dahb1 (combined treatment) at two different doses (10(5) and 10(7) cfu mL(-1)). The growth, immune (myeloperoxidase, respiratory burst, natural complement haemolytic and lysozyme activity) and antioxidant (glutathione-S-transferase, reduced glutathione and total glutathione) responses of P. hypophthalmus were reduced after post infection of GFP tagged V. parahaemolyticus Dahv2 compared to control. However, after administration with the probiotic B. licheniformis Dahb1 at 10(5) cfu mL(-1), P. hypophthalmus showed significant increase in the growth, immune and antioxidant responses compared to 10(7) cfu mL(-1). On the otherhand, the growth, immune and antioxidant responses of P. hypophthalmus infected and administrated with combined GFP tagged Vibrio + Bacillus at 10(5) cfu mL(-1) were relatively higher than that of GFP tagged V. parahaemolyticus Dahv2 and control groups but lower than that of probiotic B. licheniformis Dahb1 groups. The results of the present study conclude that the probiotic B. licheniformis Dahb1 at 10(5) cfu mL(-1) has the potential to protect the P. hypophthalmus against V. parahaemolyticus Dahv2

  14. New nematode species, Orientatractis mekongensis n. sp. (Atractidae) and Neosynodontisia suratthaniensis n. g., n. sp. (Pharyngodonidae) from freshwater fishes in Thailand.

    PubMed

    Moravec, František; Kamchoo, Kanda; Pachanawan, Adithepchaikarn

    2015-11-01

    Based on light and scanning electron microscopical studies, two new species of nematode parasites are described from freshwater fishes in Thailand: Orientatractis mekongensis n. sp. (Atractidae) from the intestine of Pangasius bocourti Sauvage (type-host) and Helicophagus leptorhynchus Ng & Kottelat (both Pangasiidae, Siluriformes), and Neosynodontisia suratthaniensis n. sp. (Pharyngodonidae) from the intestine of Labiobarbus siamensis (Sauvage) (Cyprinidae, Cypriniformes), for which a new genus Neosynodontisia n. g. is established. Orientatractis mekongensis is mainly characterised by the number and distribution of caudal papillae (2 preanal, 1 adanal and 5 postanal pairs), the length of the left spicule (306-384 µm) and large body sizes (length of males and gravid females 5.4-6.7 mm and 7.8-9.0 mm, respectively). Neosynodontisia differs from other pharyngodonid genera with representatives parasitic in fishes not only by some morphological features (mouth withdrawn into the cephalic end with inflated cuticle, structure of the male caudal end, filamented eggs), but mainly by the occurrence of males inside the body of females. A key to the genera of the Pharyngodonidae with representatives parasitising fishes is provided. PMID:26446542

  15. Antimicrobial Resistance of Escherichia coli, Enterococci, Pseudomonas aeruginosa, and Staphylococcus aureus from Raw Fish and Seafood Imported into Switzerland.

    PubMed

    Boss, Renate; Overesch, Gudrun; Baumgartner, Andreas

    2016-07-01

    A total of 44 samples of salmon, pangasius (shark catfish), shrimps, and oysters were tested for the presence of Escherichia coli, enterococci, Pseudomonas aeruginosa, and Staphylococcus aureus, which are indicator organisms commonly used in programs to monitor antibiotic resistance. The isolated bacterial strains, confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectroscopy, were tested against a panel of 29 antimicrobial agents to obtain MICs. Across the four sample types, Enterococcus faecalis (59%) was most common, followed by E. coli (55%), P. aeruginosa (27%), and S. aureus (9%). All bacterial species were resistant to some antibiotics. The highest rates of resistance were in E. faecalis to tetracycline (16%), in E. coli to ciprofloxacin (22%), and in S. aureus to penicillin (56%). Antibiotic resistance was found among all sample types, but salmon and oysters were less burdened than were shrimps and pangasius. Multidrug-resistant (MDR) strains were exclusively found in shrimps and pangasius: 17% of pangasius samples (MDR E. coli and S. aureus) and 64% of shrimps (MDR E. coli, E. faecalis, and S. aureus). Two of these MDR E. coli isolates from shrimps (one from an organic sample) were resistant to seven antimicrobial agents. Based on these findings, E. coli in pangasius, shrimps, and oysters, E. faecalis in pangasius, shrimps, and salmon, and P. aeruginosa in pangasius and shrimps are potential candidates for programs monitoring antimicrobial resistance. Enrichment methods for the detection of MDR bacteria of special public health concern, such as methicillin-resistant S. aureus and E. coli producing extended-spectrum β-lactamases and carbapenemases, should be implemented. PMID:27357045

  16. Exploring the climate change concerns of striped catfish producers in the Mekong Delta, Vietnam.

    PubMed

    Nguyen, Anh Lam; Truong, Minh Hoang; Verreth, Johan Aj; Leemans, Rik; Bosma, Roel H; De Silva, Sena S

    2015-01-01

    This study investigated the perceptions on and adaptations to climate change impacts of 235 pangasius farmers in the Mekong Delta, Vietnam. Data were collected using semi-structured household surveys in six provinces, from three regions along the Mekong river branches. A Chi-Square test was used to determine the association between variables, and a logit regression model was employed to identify factors correlated with farmer's perception and adaptation. Less than half of respondents were concerned about climate change and sought suitable adaptation measures to alleviate its impacts. Improving information on climate change and introducing early warning systems could improve the adaptive capacity of pangasius farmers, in particularly for those farmers, who were not concerned yet. Farmers relied strongly on technical support from government agencies, but farmers in the coastal provinces did not express the need for training by these institutions. This contrasting result requires further assessment of the effectiveness of adaptation measures such as breeding salinity tolerant pangasius. PMID:25674502

  17. 76 FR 81913 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Extension of Time Limit for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-29

    ... Administrative Review, 76 FR 55872 (September 9, 2011) (``Preliminary Results''). \\2\\ See Memoranda to Interested..., Import Administration, Office 9, to the FAO; RE: Questions for the United Nations Food and Agricultural Organization (``FAO'') Regarding Price Data for Pangasius Fish, dated (December 11, 2011). Extension of...

  18. Mitochondrial genome of the shorthead catfish (Pelteobagrus eupogon): structure, phylogeny, and intraspecific variation.

    PubMed

    Wang, R-Q; Wang, D-Z; Li, C-T; Yang, X-R

    2016-01-01

    The complete 16,532-nucleotide sequence of the mitochondrial genome of the shorthead catfish (Pelteobagrus eupogon) was determined using the long and accurate polymerase chain reaction method, and compared with the mitochondrial genome sequences of 49 other catfish species belonging to the order Siluriformes. The locations of protein-coding genes and ribosomal ribonucleic acids (RNAs) were identified by comparison with known sequences of other catfishes, including P. fulvidraco and P. nitidus. The P. eupogon mitochondrial genome was composed of 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNA genes, and a non-coding control region. The gene order was identical to that of other Siluriformes. Phylogenetic analyses based on mitochondrial 12S ribosomal RNA, 16S ribosomal RNA, and 13 protein-coding gene sequence data sets were carried out to further clarify the relative phylogenetic position of P. eupogon, and identify phylogenetic relationships among 24 families of Siluriformes. Phylogenetic analyses Randomized Axelerated Maximum Likelihood (RAxML) 8.0.X were congruent with a basal split of the order into Clupeiformes, Characiformes, Cypriniformes, and Siluriformes, and supported a closer relationship of P. eupogon with Amblycipitidae than Siluridae. We therefore concluded that this species appears to be closely related to the Amblycipitidae. In the phylogenetic tree, the Amblycipitidae appeared as the most basal extant lineage within the Siluriformes, while the Bagridae appeared as the sister group of Cranoglanididae and Pangasiidae. The mitochondrial genome sequence of P. eupogon has been deposited in GenBank (accession No. KJ001784). PMID:27323031

  19. DNA Barcoding of Catfish: Species Authentication and Phylogenetic Assessment

    PubMed Central

    Wong, Li Lian; Peatman, Eric; Lu, Jianguo; Kucuktas, Huseyin; He, Shunping; Zhou, Chuanjiang; Na-nakorn, Uthairat; Liu, Zhanjiang

    2011-01-01

    As the global market for fisheries and aquaculture products expands, mislabeling of these products has become a growing concern in the food safety arena. Molecular species identification techniques hold the potential for rapid, accurate assessment of proper labeling. Here we developed and evaluated DNA barcodes for use in differentiating United States domestic and imported catfish species. First, we sequenced 651 base-pair barcodes from the cytochrome oxidase I (COI) gene from individuals of 9 species (and an Ictalurid hybrid) of domestic and imported catfish in accordance with standard DNA barcoding protocols. These included domestic Ictalurid catfish, and representative imported species from the families of Clariidae and Pangasiidae. Alignment of individual sequences from within a given species revealed highly consistent barcodes (98% similarity on average). These alignments allowed the development and analyses of consensus barcode sequences for each species and comparison with limited sequences in public databases (GenBank and Barcode of Life Data Systems). Validation tests carried out in blinded studies and with commercially purchased catfish samples (both frozen and fresh) revealed the reliability of DNA barcoding for differentiating between these catfish species. The developed protocols and consensus barcodes are valuable resources as increasing market and governmental scrutiny is placed on catfish and other fisheries and aquaculture products labeling in the United States. PMID:21423623

  20. How to Determine the Geographical Origin of Seafood?

    PubMed

    El Sheikha, Aly Farag; Montet, Didier

    2016-01-01

    Traceability of seafood is a much needed service for the seafood industry. Current ways of tracing seafood are minimal while tracing of shellfish is nearly nonexistent. Tracing fish and shellfish are necessary for indicating where the fish and shellfish were fished from, farmed and packed from. This study reviews history of traceability of aquaculture and analytical approaches to verify the origin of seafood. It then describes the new molecular technique of the traceability by using PCR-DGGE to discriminate the geographical origin of fish (cases studies of Pangasius fish from Viet Nam and Sea bass fish from France) by analysis the DNA fragments of microorganisms (bacteria) on fish. This method is based on the assumption that the microbial communities of food are specific to a geographic area. PMID:24834835

  1. Investigation of a novel approach for aquaculture site selection.

    PubMed

    Falconer, Lynne; Telfer, Trevor C; Ross, Lindsay G

    2016-10-01

    This study investigated the potential use of two "species distribution models" (SDMs), Mahalanobis Typicality and Maxent, for aquaculture site selection. SDMs are used in ecological studies to predict the spatial distribution of species based on analysis of conditions at locations of known presence or absence. Here the input points are aquaculture sites, rather than species occurrence, thus the models evaluate the parameters at the sites and identify similar areas across the rest of the study area. This is a novel approach that avoids the need for data reclassification and weighting which can be a source of conflict and uncertainty within the commonly used multi-criteria evaluation (MCE) technique. Using pangasius culture in the Mekong Delta, Vietnam, as a case study, Mahalanobis Typicality and Maxent SDMs were evaluated against two models developed using the MCE approach. Mahalanobis Typicality and Maxent assess suitability based on similarity to existing farms, while the MCE approach assesses suitability using optimal values for culture. Mahalanobis Typicality considers the variables to have equal importance whereas Maxent analyses the variables to determine those which influence the distribution of the input data. All of the models indicate there are suitable areas for culture along the two main channels of the Mekong River which are currently used to farm pangasius and also inland in the north and east of the study area. The results show the Mahalanobis Typicality model had more high scoring areas and greater overall similarity than Maxent to the MCE outputs, suggesting, for this case study, it was the most appropriate SDM for aquaculture site selection. With suitable input data, a combined SDM and MCE model would overcome limitations of the individual approaches, allowing more robust planning and management decisions for aquaculture, other stakeholders and the environment. PMID:27444724

  2. Methyl mercury in fish--a case study on various samples collected from Ganges river at West Bengal.

    PubMed

    Pal, Moumita; Ghosh, Santinath; Mukhopadhyay, Madhumita; Ghosh, Mahua

    2012-06-01

    This study investigated the presence of total mercury (Hg) and organic mercury levels in the muscle of 19 common fresh water fish species captured from river Ganges, West Bengal, India. The total mercury level found in our study may not cause any toxic effect, but the methyl mercury (MeHg) level in some freshwater fish species was surprisingly very high and toxically unacceptable. The results of mercury analysis in various specimens indicated that some fish muscles tended to accumulate high levels of Hg, and approximately 50-84% of Hg was organic mercury. A strong positive correlation between mercury levels in muscle with food habit and fish length (age) was found. Wallago attu possessed the highest amount of organic mercury in their muscle tissues, and it was 0.93 ± 0.61 μg Hg/g of wet weight. Whereas in small-sized fishes Eutropiichthys murius, Puntius sarana, Cirrhinus mrigala, Mystus vittatus or Mystus gulio, and Tilapia mossambicus, it was below the detection limit. Contamination in Catla catla (0.32 ± 0.11), Anguilla bengalensis bengalensis (0.26 ± 0.07 μg Hg/g), Chitala chitala (0.25 ± 0.18), Rita rita (0.34 ± 0.14), and Ompok pabda (0.26 ± 0.04) was also above the 0.25 μg Hg/g of wet weight, the limit set by the PFA for the maximum level for consumption of fish exposed to MeHg. Though in Labeo rohita (0.12 ± 0.03), Mastacembelus armatus (0.17 ± 0.02), Pangasius pangasius (0.12 ± 0.16), Bagarius bagarius (0.12 ± 0.01), and Clupisoma garua (0.1 ± 0.01), concentration was below the recommended level, in Lates calcarifer (0.23 ± 0.0) and Mystus aor (0.23 ± 0.1), it was threatening. Interestingly, a low concentration of Hg was found in post-monsoon samples. PMID:21713467

  3. Isolation of heat-tolerant myoglobin from Asian swamp eel Monopterus albus.

    PubMed

    Chotichayapong, Chatrachatchaya; Wiengsamut, Kittipong; Chanthai, Saksit; Sattayasai, Nison; Tamiya, Toru; Kanzawa, Nobuyuki; Tsuchiya, Takahide

    2012-10-01

    Myoglobin from Asian swamp eel Monopterus albus was purified from fish muscle using salt fractionation followed by column chromatography and molecular filtration. The purified Mb of 0.68 mg/g wet weight of muscle was determined for its molecular mass by MALDI-TOF-MS to be 15,525.18 Da. Using isoelectric focusing technique, the purified Mb showed two derivatives with pI of 6.40 and 7.12. Six peptide fragments of this protein identified by LC-MS/MS were homologous to Mbs of sea raven Hemitripterus americanus, yellowfin tuna Thunnus albacores, blue marlin Makaira nigicans, common carp Cyprinus carpio, and goldfish Carassius auratus. According to the Mb denaturation, the swamp eel Mb had thermal stability higher than walking catfish Clarias batrachus Mb and striped catfish Pangasius hypophthalmus Mb, between 30 and 60 (°)C. For the thermal stability of Mb, the swamp eel Mb showed a biphasic behavior due to the O(2) dissociation and the heme orientation disorder, with the lowest increase in both Kd(f) and Kd(s). The thermal sensitivity of swamp eel Mb was lower than those of the other Mbs for both of fast and slow reaction stages. These results suggest that the swamp eel Mb globin structure is thermally stable, which is consistent with heat-tolerant behavior of the swamp eel particularly in drought habitat. PMID:22538454

  4. Product Carbon Footprints and Their Uncertainties in Comparative Decision Contexts

    PubMed Central

    Dao, Hai M.; Phan, Lam T.; de Snoo, Geert R.

    2015-01-01

    In response to growing awareness of climate change, requests to establish product carbon footprints have been increasing. Product carbon footprints are life cycle assessments restricted to just one impact category, global warming. Product carbon footprint studies generate life cycle inventory results, listing the environmental emissions of greenhouse gases from a product’s lifecycle, and characterize these by their global warming potentials, producing product carbon footprints that are commonly communicated as point values. In the present research we show that the uncertainties surrounding these point values necessitate more sophisticated ways of communicating product carbon footprints, using different sizes of catfish (Pangasius spp.) farms in Vietnam as a case study. As most product carbon footprint studies only have a comparative meaning, we used dependent sampling to produce relative results in order to increase the power for identifying environmentally superior products. We therefore argue that product carbon footprints, supported by quantitative uncertainty estimates, should be used to test hypotheses, rather than to provide point value estimates or plain confidence intervals of products’ environmental performance. PMID:25781175

  5. Antimicrobial susceptibility pattern of Edwardsiella ictaluri isolates from natural outbreaks of bacillary necrosis of Pangasianodon hypophthalmus in Vietnam.

    PubMed

    Tu, Thanh Dung; Haesebrouck, Freddy; Nguyen, Anh Tuan; Sorgeloos, Patrick; Baele, Margo; Decostere, Annemie

    2008-12-01

    The purpose of this study was to assess the in vitro susceptibility of 64 Vietnamese isolates of Edwardsiella ictaluri, the causal agent of the infectious disease Bacillus Necrosis Pangasius in Pangasianodon hypophthalmus, using the agar dilution technique. All isolates originated from different farms and were collected between 2002 and 2005. None of the isolates displayed acquired resistance to amoxicillin, amoxicillin-clavulanic acid, chloramphenicol, florfenicol, gentamicin, kanamycin, neomycin, and nitrofurantoin. Acquired resistance to streptomycin was detected in 83%, to oxytetracycline in 81%, and to trimethoprim in 71% of the isolates, as indicated by a bimodal distribution of the minimal inhibitory concentrations (MICs) of these antimicrobials. The MICs of enrofloxacin displayed a monomodal distribution with tailing toward the higher MIC values, possibly indicating reduced susceptibility of a minority of isolates (3 out of the 64). For the quinolone antimicrobial agents flumequin and oxolinic acid, acquired resistance was encountered in 8% and 6% of the strains, respectively. All strains were intrinsically resistant to the polypeptide antimicrobial agent colistin. Seventy-three percent of the isolates were shown to have acquired resistance to at least three antimicrobial agents. The results of this study emphasize the strict need to control both the prophylactic and curative use of antimicrobial agents in Vietnamese aquaculture. PMID:19090723

  6. Genetic variation and population structure of endemic yellow catfish, Horabagrus brachysoma (Bagridae) among three populations of Western Ghat region using RAPD and microsatellite markers.

    PubMed

    Abdul Muneer, P M; Gopalakrishnan, A; Musammilu, K K; Mohindra, Vindhya; Lal, K K; Basheer, V S; Lakra, W S

    2009-09-01

    Random amplified polymorphic DNA (RAPD) and microsatellite markers were applied to evaluate the genetic variation in endemic and endangered yellow catfish, Horabagrus brachysoma sampled from three geographic locations of Western Ghat, South India river systems. In RAPD, of 32 10-mer RAPD primers screened initially, 10 were chosen and used in a comparative analysis of H. brachysoma collected from Meenachil, Chalakkudy and Nethravathi River systems. Of the 124 total RAPD fragments amplified, 49 (39.51%) were found to be shared by individuals of all 3 populations. The remaining 75 fragments were found to be polymorphic (60.48%). In microsatellites, six polymorphic microsatellite loci were identified by using primers developed for Pangasius hypophthalmus, Clarias macrocephalus and Clarias gariepinus. The identified loci were confirmed as microsatellite by sequencing after making a clone. The nucleotide sequences of 6 loci were published in NCBI genbank. The number of alleles across the six loci ranged from 4 to 7 and heterozygosities ranged from 0.07 to 0.93. The mean number of alleles and effective number of alleles per locus were 5.00 and 3.314, respectively. The average heterozygosity across all investigated samples was 0.72, indicating a significant deficiency of heterozygotes in this species. RAPD and microsatellite methods reported a high degree of gene diversity and genetic distances depicted by UPGMA dendrograms among the populations of H. brachysoma. PMID:18979230

  7. Product carbon footprints and their uncertainties in comparative decision contexts.

    PubMed

    Henriksson, Patrik J G; Heijungs, Reinout; Dao, Hai M; Phan, Lam T; de Snoo, Geert R; Guinée, Jeroen B

    2015-01-01

    In response to growing awareness of climate change, requests to establish product carbon footprints have been increasing. Product carbon footprints are life cycle assessments restricted to just one impact category, global warming. Product carbon footprint studies generate life cycle inventory results, listing the environmental emissions of greenhouse gases from a product's lifecycle, and characterize these by their global warming potentials, producing product carbon footprints that are commonly communicated as point values. In the present research we show that the uncertainties surrounding these point values necessitate more sophisticated ways of communicating product carbon footprints, using different sizes of catfish (Pangasius spp.) farms in Vietnam as a case study. As most product carbon footprint studies only have a comparative meaning, we used dependent sampling to produce relative results in order to increase the power for identifying environmentally superior products. We therefore argue that product carbon footprints, supported by quantitative uncertainty estimates, should be used to test hypotheses, rather than to provide point value estimates or plain confidence intervals of products' environmental performance. PMID:25781175

  8. Biological Activities of Tetrodotoxin-Producing Enterococcus faecium AD1 Isolated from Puffer Fishes.

    PubMed

    Nguyen, Tu Hoang Khue; Nguyen, Huu Ngoc; Nghe, Dat Van; Nguyen, Kim Hoang

    2015-01-01

    Puffer fishes were collected from the central sea in Vietnam from spring to summer season. The eggs were incubated in MRS broth that was used to test the toxicity in mice and isolate the lactic acid bacteria community that could produce tetrodotoxin (TTX). Thin layer chromatography (TLC) and high performance lipid chromatography (HPLC) were used to detect and quantify TTX. As a result, Enterococcus faecium AD1 which was identified by biochemical test and 16S rRNA analysis could produce TTX 0.3 mg/mL when cultured in MRS broth. The bacterium was optimized for TTX production and gave 0.18 mg/mL, 0.07 mg/mL, and 0.15 mg/mL in media prepared from the meat-washing water of freshwater fishes (Pangasius bocourti, Oreochromis sp.) and sea fish (Auxis thazard), respectively, that are also hopeful to answer some poisoning cases related to eating fishes. Enterococcus faecium also showed the wide antimicrobial activities on yeast, Gram-negative and -positive bacteria. Extracted exopolysaccharide (EPS) that reacted with 2,2-diphenyl-1-picrylhydrazyl to give IC50 at 5 mg/mL equaled 11 mg/mL ascorbic acid which could show effects on Hela-6 and Hep G2 using sulforhodamine B test. Enterococcus faecium can be claimed as a promising source in tetrodotoxin and biological compounds. PMID:26380310

  9. Biological Activities of Tetrodotoxin-Producing Enterococcus faecium AD1 Isolated from Puffer Fishes

    PubMed Central

    Nguyen, Tu Hoang Khue; Nguyen, Huu Ngoc; Nghe, Dat Van; Nguyen, Kim Hoang

    2015-01-01

    Puffer fishes were collected from the central sea in Vietnam from spring to summer season. The eggs were incubated in MRS broth that was used to test the toxicity in mice and isolate the lactic acid bacteria community that could produce tetrodotoxin (TTX). Thin layer chromatography (TLC) and high performance lipid chromatography (HPLC) were used to detect and quantify TTX. As a result, Enterococcus faecium AD1 which was identified by biochemical test and 16S rRNA analysis could produce TTX 0.3 mg/mL when cultured in MRS broth. The bacterium was optimized for TTX production and gave 0.18 mg/mL, 0.07 mg/mL, and 0.15 mg/mL in media prepared from the meat-washing water of freshwater fishes (Pangasius bocourti, Oreochromis sp.) and sea fish (Auxis thazard), respectively, that are also hopeful to answer some poisoning cases related to eating fishes. Enterococcus faecium also showed the wide antimicrobial activities on yeast, Gram-negative and -positive bacteria. Extracted exopolysaccharide (EPS) that reacted with 2,2-diphenyl-1-picrylhydrazyl to give IC50 at 5 mg/mL equaled 11 mg/mL ascorbic acid which could show effects on Hela-6 and Hep G2 using sulforhodamine B test. Enterococcus faecium can be claimed as a promising source in tetrodotoxin and biological compounds. PMID:26380310

  10. Immunological cross-reactivity between four distant parvalbumins-Impact on allergen detection and diagnostics.

    PubMed

    Sharp, Michael F; Stephen, Juan N; Kraft, Lukas; Weiss, Thomas; Kamath, Sandip D; Lopata, Andreas L

    2015-02-01

    Fish are the largest and most diverse group of vertebrates. Fish are also a part of the eight food groups that cause the majority of IgE mediated food reactions. Detection tools for fish allergens are however limited due to the great diversity of fish species, despite fish allergy and its major allergen parvalbumin being well documented. The most commonly studied fish are frequently consumed in North America and Europe. However, much less is known about fish allergens in the Australasian region although fish is widely consumed in this region. A comprehensive phylogenetic analysis was performed of known parvalbumin amino acid sequences to determine possible candidate antigens for new cross-reactive antibodies to be used to detect most fish parvalbumins. Polyclonal rabbit antibodies were raised against parvalbumins from frequently consumed barramundi (Lates calcarifer), basa (Pangasius bocourti), pilchard (Sardinops sagax) and Atlantic salmon (Salmo salar). These were evaluated for cross-reactivity against a panel of 45 fish extracts (raw, heated and canned fish). Anti-barramundi parvalbumin proved to be the most cross-reactive antibody, detecting 87.5% of the 40 species analyzed, followed by anti-pilchard and anti-basa antibody. In contrast the anti-salmon antibody was very specific and only reacted to salmonidae and a few other fish. All analyzed fish species, except mahi mahi, swordfish, yellowfin tuna and all 5 canned fish had parvalbumin detected in raw extracts. However antibody reactivity to many fish was heat liable or susceptible to denaturation, demonstrating that some parvalbumins have most likely conformational epitopes, which lose antibody reactivity after heat treatment. We have demonstrated the generation of highly cross-reactive anti-parvalbumin antibodies that could be used for the detection of allergenic fish parvalbumin in contaminated food products. This cross-reactivity study thus shows processing of fish, especially canning, can have on impact

  11. Probabilistic risk assessment of veterinary medicines applied to four major aquaculture species produced in Asia.

    PubMed

    Rico, Andreu; Van den Brink, Paul J

    2014-01-15

    Aquaculture production constitutes one of the main sources of pollution with veterinary medicines into the environment. About 90% of the global aquaculture production is produced in Asia and the potential environmental risks associated with the use of veterinary medicines in Asian aquaculture have not yet been properly evaluated. In this study we performed a probabilistic risk assessment for eight different aquaculture production scenarios in Asia by combining up-to-date information on the use of veterinary medicines and aquaculture production characteristics. The ERA-AQUA model was used to perform mass balances of veterinary medicinal treatments applied to aquaculture ponds and to characterize risks for primary producers, invertebrates, and fish potentially exposed to chemical residues through aquaculture effluents. The mass balance calculations showed that, on average, about 25% of the applied drug mass to aquaculture ponds is released into the environment, although this percentage varies with the chemical's properties, the mode of application, the cultured species density, and the water exchange rates in the aquaculture pond scenario. In general, the highest potential environmental risks were calculated for parasitic treatments, followed by disinfection and antibiotic treatments. Pangasius catfish production in Vietnam, followed by shrimp production in China, constitute possible hot-spots for environmental pollution due to the intensity of the aquaculture production and considerable discharge of toxic chemical residues into surrounding aquatic ecosystems. A risk-based ranking of compounds is provided for each of the evaluated scenarios, which offers crucial information for conducting further chemical and biological field and laboratory monitoring research. In addition, we discuss general knowledge gaps and research priorities for performing refined risk assessments of aquaculture medicines in the near future. PMID:24061054

  12. Comparison of Asian Aquaculture Products by Use of Statistically Supported Life Cycle Assessment.

    PubMed

    Henriksson, Patrik J G; Rico, Andreu; Zhang, Wenbo; Ahmad-Al-Nahid, Sk; Newton, Richard; Phan, Lam T; Zhang, Zongfeng; Jaithiang, Jintana; Dao, Hai M; Phu, Tran M; Little, David C; Murray, Francis J; Satapornvanit, Kriengkrai; Liu, Liping; Liu, Qigen; Haque, M Mahfujul; Kruijssen, Froukje; de Snoo, Geert R; Heijungs, Reinout; van Bodegom, Peter M; Guinée, Jeroen B

    2015-12-15

    We investigated aquaculture production of Asian tiger shrimp, whiteleg shrimp, giant river prawn, tilapia, and pangasius catfish in Bangladesh, China, Thailand, and Vietnam by using life cycle assessments (LCAs), with the purpose of evaluating the comparative eco-efficiency of producing different aquatic food products. Our starting hypothesis was that different production systems are associated with significantly different environmental impacts, as the production of these aquatic species differs in intensity and management practices. In order to test this hypothesis, we estimated each system's global warming, eutrophication, and freshwater ecotoxicity impacts. The contribution to these impacts and the overall dispersions relative to results were propagated by Monte Carlo simulations and dependent sampling. Paired testing showed significant (p < 0.05) differences between the median impacts of most production systems in the intraspecies comparisons, even after a Bonferroni correction. For the full distributions instead of only the median, only for Asian tiger shrimp did more than 95% of the propagated Monte Carlo results favor certain farming systems. The major environmental hot-spots driving the differences in environmental performance among systems were fishmeal from mixed fisheries for global warming, pond runoff and sediment discards for eutrophication, and agricultural pesticides, metals, benzalkonium chloride, and other chlorine-releasing compounds for freshwater ecotoxicity. The Asian aquaculture industry should therefore strive toward farming systems relying upon pelleted species-specific feeds, where the fishmeal inclusion is limited and sourced sustainably. Also, excessive nutrients should be recycled in integrated organic agriculture together with efficient aeration solutions powered by renewable energy sources. PMID:26512735

  13. Copper use and accumulation in catfish culture in the Mekong Delta, Vietnam.

    PubMed

    Marcussen, Helle; Løjmand, Helle; Dalsgaard, Anders; Hai, Dao M; Holm, Peter E

    2014-01-01

    Aquaculture of Pangasius hypophthalmus (striped catfish) in Vietnam reached 1.1 million tonnes in 2011 and catfish fillets are exported worldwide. The intensive cultures of catfish mainly in earth ponds have made it necessary to apply CuSO4 and other chemicals to control external parasites and other pathogens. However, accumulation of Cu in aquaculture ponds may pose a hazard to growth of fish or to the aquatic environment. The aim of this study was to determine accumulation of Cu in sediment, water and fish in a catfish pond with a history of repeated treatment with CuSO4 in the Mekong Delta, Vietnam. Copper concentrations in pond sediment were in the interval 21.3-45.7 mg kg(-1) dw and did not exceed the Vietnamese values for soil to be used for agricultural production (70 mg kg(-1) dw.). During three samplings the total mean concentration of Cu in pond water (4 μg L(-1)) did not exceed the LC50-value (70 μg L(-1)) for catfish and the mean dissolved concentration of Cu (0.986 μg L(-1)) did not seem to constitute a risk for the stability of the aquatic ecosystem. No significant variation in Cu concentrations between sampling sites in the pond and depth of sediment profile were determined. The accumulation of Cu in catfish was highest in the liver compared to the skin, gills and muscle tissue. With the current practice of removing pond sludge three to four times during a production cycle little if any Cu seems to accumulate in catfish ponds despite repeated anti-parasite treatments with CuSO4. Further studies are needed to assess the eco-toxicity and impact on agricultural production when pond sediment is discharged into aquatic recipients and used as soil fertilizer. PMID:24171418

  14. Optimisation and standardisation of functional immune assays for striped catfish (Pangasianodon hypophthalmus) to compare their immune response to live and heat killed Aeromonas hydrophila as models of infection and vaccination.

    PubMed

    Sirimanapong, Wanna; Thompson, Kim D; Kledmanee, Kan; Thaijongrak, Prawporn; Collet, Bertrand; Ooi, Ei Lin; Adams, Alexandra

    2014-10-01

    Aquaculture production of Pangasianodon hypophthalmus is growing rapidly in South East Asia, especially in Vietnam. As it is a relatively new aquaculture species there are few reports evaluating its immune response to pathogens. Thus, functional assays for P. hypophthalmus were optimised to evaluate both innate and adaptive immune responses, and were then used to examine immune response following stimulation with live and heat-killed Aeromonas hydrophila. These were used as models of infection and vaccination, respectively. Four treatment groups were used, including a control group, a group injected intraperitonally (IP) with adjuvant only, a group injected with heat-killed A. hydrophila (1 × 10(9) cfu ml(-1) mixed with adjuvant), and a group injected with a subclinical dose of live A. hydrophila. Samples were collected at 0, 1, 3, 7, 14 and 21 days post-injection (d.p.i.) to assess their immune response. The results indicated that challenge with live or dead bacteria stimulated the immune response in P. hypophthalmus significantly above the levels observed in control groups with respect to specific antibody titre, plasma lysozyme and peroxidase activity, and phagocytosis by head kidney macrophages at 7 or/and 14 d.p.i. At 21 d.p.i., total and specific antibody (IgM) levels and plasma lysozyme activity in fish injected with either live or dead A. hydrophila were significantly different to the control groups. Differential immune responses were observed between fish injected with either live or dead bacteria, with live A. hydrophila significantly stimulating an increase in WBC counts and plasma peroxidase activity at 3 d.p.i., with the greatest increase in WBC counts noted at 21 d.p.i. and in phagocytosis at 14 d.p.i. By 21 d.p.i. only the macrophages from fish injected with dead A. hydrophila showed significantly stimulation in their respiratory burst activity. This study provides basic information on the immune response in pangasius catfish that can be useful in

  15. Specific IgE to fish extracts does not predict allergy to specific species within an adult fish allergic population

    PubMed Central

    2014-01-01

    Background Fish is an important cause of food allergy. Studies on fish allergy are scarce and in most cases limited to serological evaluation. Our objective was to study patterns of self-reported allergy and tolerance to different commonly consumed fish species and its correlation to IgE sensitization to the same species. Methods Thirty-eight adult fish allergic patients completed a questionnaire regarding atopy, age of onset and symptoms to 13 commonly consumed fish species in the Netherlands (pangasius, cod, herring, eel, hake, pollock, mackerel, tilapia, salmon, sardine, tuna, plaice and swordfish). Specific IgE to these fish extracts were analyzed by ImmunoCAP. Results Median age of onset of fish allergy was 8.5 years. Severe reactions were reported by the majority of patients (n = 20 (53%) respiratory and of these 20 patients, 6 also had cardiovascular symptoms). After diagnosis, 66% of the patients had eliminated all fish from their diet. Allergy to all species ever tried was reported by 59%. In relation to species ever tried, cod (84%) and herring (79%) were the most frequently reported culprit species while hake (57%) and swordfish (55%) were the least frequent. A positive sIgE (value ≥ 0.35 kUA/L) to the culprit species ranged between 50% (swordfish) and 100% (hake). In tolerant patients, a negative sIgE (value < 0.35 kUA/L) ranged from 0% (hake, pollock and swordfish) to 75% (sardine). For cod, the agreement between sIgE test results and reported allergy or tolerance was 82% and 25%, respectively. Sensitization to cod parvalbumin (Gad c 1) was present in 77% of all patients. Conclusion Serological cross-reactivity between fish species is frequent, but in a significant proportion of patients, clinical relevance appears to be limited to only certain species. A well-taken history or food challenge is required for discrimination between allergy to the different fish species. PMID:25225608