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1.
J Hazard Mater ; 421: 126708, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34352521

RESUMO

The level and distribution of 16 USEPA Polycyclic aromatic hydrocarbon (PAHs) in aquaculture farmed fish (Mugil cephalus and Oreochromis mossambicus) and shellfish (Corbicula fluminea Formosa and Meretrix lusoria) were determined in Taiwan and then assessed cancer and non-cancer risks for those consuming these kinds of seafood. Results indicated that C. fluminea Formosa accumulated the highest average concentration of total PAHs (43.0 ± 11.3 ng/g wet weight) while M. lusoria contained the lowest concentration (20.0 ± 5.8 ng/g) among all species. The low-molecular-weight PAHs were dominant for both fish and shellfish, which consistent with other studies. Notably, parts of high-molecular-weight PAHs were found in shellfish whereas that was little in fish. The calculated hazard quotients (HQ) of all PAHs were smaller than 1 and the incremental lifetime cancer risks (ILCR) for Benzo[a]pyrene were below 1 × 10-5, suggesting that PAHs in the collected seafood could pose a low hazard to residents. Although the results indicated that the studied seafood is safe for human consumption, children and seniors post relatively higher risks, suggesting that it needs to continue monitoring and control the PAHs concentration in seafood and the associated environments.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Animais , Aquicultura , Criança , Monitoramento Ambiental , Contaminação de Alimentos/análise , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Lagoas , Medição de Risco , Alimentos Marinhos/análise , Taiwan
2.
J Hazard Mater ; 421: 126712, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34388919

RESUMO

Aquaculture is increasing at the global scale, and beneficial reuse of wastewater is becoming crucial in some regions. Here we selected a unique tertiary treatment system for study over a one-year period. This experimental ecosystem-based approach to effluent management included a treated wastewater pond (TWP), which receives 100% effluent from a wastewater treatment plant, and an aquaculture pond (AP) that receives treated water from the TWP for fish production. We examined the fate of a wide range of pharmaceutically active compounds (PhACs) in this TWP-AP system and a control pond fed by river water using traditional grab sampling and passive samplers. We then employed probabilistic approaches to examine exposure hazards. Telmisartan, carbamazepine, diclofenac and venlafaxine, exceeded ecotoxicological predicted no effect concentrations in influent wastewater to the TWP, but these water quality hazards were consistently reduced following treatment in the TWP-AP system. In addition, both grab and passive sampling approaches resulted in similar occurrence patterns of studied compounds, which highlights the potential of POCIS use for water monitoring. Based on the approach taken here, the TWP-AP system appears useful as a tertiary treatment step to reduce PhACs and decrease ecotoxicological and antibiotic resistance water quality hazards prior to beneficial reuse in aquaculture.


Assuntos
Preparações Farmacêuticas , Poluentes Químicos da Água , Animais , Aquicultura , Ecossistema , Monitoramento Ambiental , Lagoas , Águas Residuárias/análise , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
3.
J Environ Manage ; 301: 113852, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34592671

RESUMO

Woodchip bioreactors are being successfully applied to remove nitrate from commercial land-based recirculating aquaculture system (RAS) effluents. In order to understand and optimize the overall function of these bioreactors, knowledge on the microbial communities, especially on the microbes with potential for production or mitigation of harmful substances (e.g. hydrogen sulfide; H2S) is needed. In this study, we quantified and characterized bacterial and fungal communities, including potential H2S producers and consumers, using qPCR and high throughput sequencing of 16S rRNA gene. We took water samples from bioreactors and their inlet and outlet, and sampled biofilms growing on woodchips and on the outlet of the three full-scale woodchip bioreactors treating effluents of three individual RAS. We found that bioreactors hosted a high biomass of both bacteria and fungi. Although the composition of microbial communities of the inlet varied between the bioreactors, the conditions in the bioreactors selected for the same core microbial taxa. The H2S producing sulfate reducing bacteria (SRB) were mainly found in the nitrate-limited outlets of the bioreactors, the main groups being deltaproteobacterial Desulfobulbus and Desulfovibrio. The abundance of H2S consuming sulfate oxidizing bacteria (SOB) was 5-10 times higher than that of SRB, and SOB communities were dominated by Arcobacter and other genera from phylum Epsilonbacteraeota, which are also capable of autotrophic denitrification. Indeed, the relative abundance of potential autotrophic denitrifiers of all denitrifier sequences was even 54% in outlet water samples and 56% in the outlet biofilm samples. Altogether, our results show that the highly abundant bacterial and fungal communities in woodchip bioreactors are shaped through the conditions prevailing within the bioreactor, indicating that the bioreactors with similar design and operational settings should provide similar function even when conditions in the preceding RAS would differ. Furthermore, autotrophic denitrifiers can have a significant role in woodchip biofilters, consuming potentially produced H2S and removing nitrate, lengthening the operational age and thus further improving the overall environmental benefit of these bioreactors.


Assuntos
Desnitrificação , Microbiota , Aquicultura , Reatores Biológicos , Nitratos , RNA Ribossômico 16S/genética
4.
J Environ Manage ; 301: 113865, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597951

RESUMO

Chlorella vulgaris (C. vulgaris) has attracted widespread attention because of its ability to absorb, enrich, and degrade typical endocrine-disrupting antibiotics (such as levofloxacin) in aquaculture wastewater. However, microplastic pollution in wastewater, which is becoming an increasingly severe problem, will exert a toxic effect on aquatic organisms (such as C. vulgaris and other microalgae). Polystyrene microplastics (PS-MPs), which are commonly found in freshwater aquaculture wastewater, are the most harmful. Therefore, clarifying the effects of PS-MPs on the ability of C. vulgaris to degrade typical endocrine-disrupting antibiotics in freshwater aquaculture wastewater and determining the mechanism of the effect are particularly important. The results of this study showed that under the stress of PS-MPs, the growth of C. vulgaris was significantly inhibited; the EPS-polysaccharide content per algal cell, EPS adsorption, intracellular enrichment and degradation of levofloxacin, total CYP450 content, and total CYP450 activity all decreased; and the relative expression of key genes related to the metabolic activity of algal cells, such as psbA, psaB, and rbcL, was generally downregulated. PS-MPs mainly affected the removal of a typical endocrine-disrupting antibiotic by C. vulgaris by altering adsorption, enrichment, and enzyme degradation. The results provide a reference for research on the impact of microplastic pollution on the treatment of freshwater aquaculture wastewater.


Assuntos
Chlorella vulgaris , Microalgas , Poluentes Químicos da Água , Aquicultura , Água Doce , Levofloxacino , Microplásticos , Plásticos , Poliestirenos , Águas Residuárias , Poluentes Químicos da Água/análise
5.
Sci Total Environ ; 802: 149800, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34525752

RESUMO

Aquaculture is one of the fastest growing food producing industries globally, providing ~50% of fish for human consumption. However, the rapid growth of aquaculture presents a range of challenges including balancing environmental impact that can be influenced by variations in climatic conditions. Monitoring of physicochemical parameters is traditionally used to evaluate aquaculture output quality; however, this approach does not indicate the cumulative ecotoxicological effects on receiving waters. Specifically, this case study investigated the relationship between measuring traditional physicochemical parameters and the health of the alga Pseudokirchneriella subcapitata in order to evaluate the potential ecotoxicological effects of freshwater aquaculture on the receiving aquatic ecosystem in the Irish midlands. This constituted the first 2-year longitudinal study conducted in 2018 and 2019 that reports on the efficacy of using algae as a natural bioindicator to monitor and assess freshwater aquaculture wastewater from a traditional flow-through fish farm producing Eurasian Perch (Perca fluviatilis); monitoring was compared over a same six-month period in the same location each year. Findings demonstrated significant differences between the two monitoring periods when using P. subcapitata for assessing the quality of aquaculture intake (P = 0.030) and output (P = 0.039). No stimulatory effects were observed during 2019 unlike >50% rates experienced the previous year. These observations coincided with changes in climatic conditions whereby the 2018 period experienced extended levels of drought; whereas non-drought conditions were observed during 2019. Findings suggest that reliance upon traditional monitoring techniques may not provide sufficient robustness or versatility to address emerging issues, such as extremes in climate variance, which may influence the future intensive sustainability of freshwater aquaculture. This research supports the complementary use of P. subcapitata as a rapid and simple early-warning bioindicator for measuring aquaculture output quality on receiving aquatic ecosystems.


Assuntos
Microalgas , Percas , Animais , Aquicultura , Ecossistema , Biomarcadores Ambientais , Humanos , Irlanda , Estudos Longitudinais , Águas Residuárias
6.
Environ Pollut ; 291: 118152, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34740287

RESUMO

The operation of the equipment in industrial recirculating aquaculture systems (RAS) affects the underwater soundscape of aquaculture tanks where fishes live. This study evaluated the influence of commercial industrial RAS noise on the growth, physiology, and behavior of juvenile largemouth bass (Micropterus salmoides). In this study, two experimental groups, the RAS noise group (115 dB re 1 µPa RMS) and the ambient group (69 dB re 1 µPa RMS), were studied. The water quality and feeding regime for each group were kept the same during the 60-day experiment. Results showed that there was no significant difference in the average daily feed intake of the fish between the two treatments, while the rate of weight gain of the ambient group (755.27 ± 65.62%) was significantly higher than that of the noise group (337.66 ± 88.01%). In addition, the RAS environmental noise also had an adverse effect on the anti-oxidation and immune systems of the fish based on results of analysis of blood, liver, and intestinal samples. Moreover, environmental noise affected the swimming behavior of the fish school. The mean angle and distance between the focal fish and its nearest neighbor fish in RAS noise group were 33.3° and 92.1 mm, respectively, which were larger than those of the ambient group with 24.4° and 89.5 mm, respectively. From the above results, RAS noise did influence the welfare of largemouth bass, and the soundscape in RAS hence should be managed in real production.


Assuntos
Bass , Animais , Aquicultura , Intestinos , Fígado/metabolismo , Oxirredução
7.
Environ Monit Assess ; 193(12): 774, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34741217

RESUMO

This research explored the long-term relationships of climate parameters and coastal water quality nearby shrimp farms in two countries. In Thailand, two sampling points in canals located in Bangkok and Trang provinces were selected as the urban and tourism areas, respectively. In northern Vietnam, the canals located in Thai Binh and Quang Ninh provinces were used as the urban and tourism areas, respectively. The diurnal monitoring of water quality and weather was performed at each site to evaluate the relationships between climate and water quality, pollution load, and risk analysis. A questionnaire was also used to assess the climate and water exposure, vulnerability, and adaptability of each site. All data were ranked on a scale of 1 to 5 to integrate each factor. It was determined that the main water quality problem was fecal pollution. Notably, aquaculture farming in northern Vietnam is more vulnerable than in Thailand; however, Vietnam farmers were adaptable for climate variability.


Assuntos
Turismo , Qualidade da Água , Aquicultura , Monitoramento Ambiental , Tailândia , Vietnã
8.
An Acad Bras Cienc ; 93(suppl 3): e20190999, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730735

RESUMO

Ovalipes trimaculatus is a highly valued fisheries resource with high potential for aquaculture production. Still, there is need for experimental information to sustain efficient husbandry practices. In this work we analyze the combined effects of different thermo-haline conditions on the length of development and survival of embryos (6, 10, 13, 15, 18, 22, 24 °C x 30, 33 ‰; 13 °C x 26, 30, 33, 37 ‰) and zoeae I (13, 18, 22 °C x 30, 33 ‰; 13 °C x 26, 30, 33, 37 ‰) from individuals sampled in the Atlantic coast of Patagonian. Among the most relevant results, it was found that the mean length of embryogenesis decreased from 63 to 19 days with increasing temperatures, but was not affected by seawater salinity. Mean embryonic survival was significantly lower at the combination of the highest temperature and salinity tested. Also, it differed between salinity conditions. Both at 30 and 33‰, the length of the Zoea I stage significantly varied between thermal treatments, being significantly longer at 13°C. No zoeae I reared at 13 °C survived at 37‰ and mean survival at 26‰ halved that of 30-33‰. Results obtained reduce aquaculture production costs.


Assuntos
Braquiúros , Salinidade , Temperatura , Animais , Aquicultura , Embrião não Mamífero
9.
Int J Syst Evol Microbiol ; 71(11)2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34779757

RESUMO

Two novel bacterial strains, designated as DN00404T and DN04309T, were isolated from aquaculture water and characterized by using a polyphasic taxonomic approach. Cells of strains DN00404T and DN04309T were Gram-stain-negative, aerobic, non-motile, oxidase-positive and catalase-positive. Cells of DN00404T were short rod-shaped and those of DN04309T were long rod-shaped. Strain DN00404T was found to grow at 15-37 °C (optimum, 25-30 °C), at pH 6.0-11.0 (optimum, pH 7.5) and in 0-2.0 % (w/v) NaCl (optimum, 1.0 %). Strain DN04309T was found to grow at 15-45 °C (optimum, 20-37 °C), at pH 5.5-11.0 (optimum, 7.5) and in 0-4.0 % (w/v) NaCl (optimum, 0.5 %). Phylogenetic analyses based on 16S rRNA gene and genome sequences revealed that the two strains belonged to the genus Sphingobacterium and were distinct from all known species of this genus. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the two strains and between each of the two strains and related type strains of this genus were well below the recognized thresholds of 95.0-96.0 % ANI and 70.0 % dDDH for species delineation. The genomic DNA G+C contents of strains DN00404T and DN04309T were 41.6 and 36.0 mol%, respectively. The respiratory quinone in both strains was identified as MK-7, and their major fatty acids were iso-C15 : 0 and summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c), which were similar to those of other species of this genus. The two major fatty acids C16 : 0 and iso-C17 : 0 3-OH were also found in strain DN00404T. Based on genotypic and phenotypic characteristics, two novel species of the genus Sphingobacterium are proposed: Sphingobacterium micropteri sp. nov. with DN00404T (=GDMCC 1.1865T=KACC 21924T) as the type strain and Sphingobacterium litopenaei sp. nov. with DN04309T (=GDMCC 1.1984T=KCTC 82348T) as the type strain.


Assuntos
Sphingobacterium , Aquicultura , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingobacterium/genética , Água
10.
Artigo em Inglês | MEDLINE | ID: mdl-34770083

RESUMO

The composition and stability of microbial communities in aquaculture water are crucial for the healthy growth of shrimp and present considerable risk to aquatic ecosystems. The modified clay (MC) method has been proposed as an efficient and safe solution for the mitigation of harmful algal blooms (HABs). Currently, the effects of MC on microbial communities in aquaculture water remain unknown. Here, we adopted the MC method to regulate shrimp-culture water quality and evaluated the effects of MC on the composition and stability of phytoplankton together with bacteria communities through high-throughput sequencing. On the one hand, a prominent change in the composition of microbial community was observed, with green algae becoming the most abundant genera and pathogens being infrequent in the MC-treated pond, which was more conducive to the growth of shrimp than that in the control pond. Moreover, MC could increase the diversity and stability of the microbial community structure in the water column, which had a higher anti-interference ability, as demonstrated by the analysis of the diversity and molecular ecological network. Taken together, MC could reduce the possibility for the occurrence of HABs and maintain a stable microbial community, which is beneficial for the health and high yield of shrimp.


Assuntos
Microbiota , Lagoas , Aquicultura , Bactérias , Argila , Fitoplâncton
11.
Dis Aquat Organ ; 147: 13-23, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34734570

RESUMO

Perkinsus sp. protozoans are parasites of a wide variety of molluscs around the world and are responsible for episodes of mass mortalities and large economic losses for aquaculture industries and fisheries. The first step towards the management of infectious episodes is the reliable detection of Perkinsus species. While historic methods for diagnosis of Perkinsus sp. infections in mollusc hosts include histological, in vitro, molecular-genetic, and immunoassays, antibody-based diagnostic assays may prove most practical with development of improved reagents and techniques. This paper reviews historic developments of antibodies against Perkinsus species, and of diagnostic immunoassays. Thirteen research papers reported the development of antibodies against Perkinsus sp. or their extracellular products, mainly P. olseni and P. marinus. Nine of those tested the cross-reactivity of their antibodies against different life stages or species than the one used as immunogen. While all antibodies raised against trophozoites labelled hypnospores, several antibodies raised against hypnospores did not label trophozoites, suggesting antigenic differences between those cell types. Antibody specificity studies showed that there is antigenic heterogeneity between Perkinsus species and Perkinsus-like organisms, and also that common epitopes occur among Perkinsus species, as well as some dinoflagellates. This review summarizes the current knowledge and aims at helping the future development of Perkinsus species-specific antibodies and immunoassays.


Assuntos
Apicomplexa , Bivalves , Dinoflagelados , Animais , Aquicultura , Imunoensaio/veterinária , Moluscos
12.
ScientificWorldJournal ; 2021: 3119958, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34594160

RESUMO

Fish and fish products are considered a fundamental part of the human diet due to their high nutritional value. Food-borne diseases are considered a major public health challenge worldwide due to their incidence, associated mortality, and negative economic repercussions. Food safety is the guarantee that foods will not cause harm to the health of those who consume them, and it is a fundamental property of food quality. Food safety can be at risk of being lost at any stage of the food chain if the food is contaminated by pathogenic microorganisms. Many diverse bacteria are present in the environment and as part of the microbiota of food that can be transmitted to humans during the handling and consumption of food. Plesiomonas shigelloides has been mainly associated with outbreaks of gastrointestinal diseases due to the consumption of fish. This bacterium inhabits the environment and aquatic animals and is associated with the microbiota of fish such as tilapia, a fish of importance in fishing, aquaculture, commercialization, and consumption worldwide. The purpose of this document is to provide, through a bibliographic review of databases (Scopus, Web of Science, and Google Scholar, among others), a general informative perspective on food-borne diseases and, in particular, the consumption of fish and tilapia. Diseases derived from contamination by Plesiomonas shigelloides are included, and control and prevention actions and sanitary regulations for fishery products established in several countries around the world are discussed to promote the safety of foods of aquatic origin intended for human consumption and to protect public health.


Assuntos
Doenças dos Peixes/microbiologia , Contaminação de Alimentos , Microbiologia de Alimentos , Gastroenterite/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Plesiomonas/isolamento & purificação , Alimentos Marinhos/microbiologia , Tilápia/microbiologia , Animais , Aquicultura , Carga Bacteriana , Criopreservação , Reservatórios de Doenças , Produtos Pesqueiros/microbiologia , Manipulação de Alimentos , Conservação de Alimentos , Inocuidade dos Alimentos , Gastroenterite/epidemiologia , Gastroenterite/etiologia , Gastroenterite/prevenção & controle , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Plesiomonas/crescimento & desenvolvimento , Prevalência , Controle de Qualidade , Poluição da Água
13.
F1000Res ; 10: 378, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34621506

RESUMO

Background Aquaculture systems for giant gourami, Osphronemus goramy Lacepède (1801), have significantly improved fish production yields and food security in Indonesia. However, these systems also cause serious problems in terms of eutrophication in waterbodies. This study analysed the nutrient loading and farm characteristics of giant gourami in floating cages in Lake Maninjau. Method A total of 20 floating cages were used to record these nutrients in feed supply, female and male juvenile fish, dead fish and harvested fish to estimate nutrient loading. Data on the harvested fish, production cycle, stock number and cage capacity were used to estimate the stocking density, feeding rate, feed efficiency, and net fish yield, and the relationship between feed supply and nutrient loading and farm characteristics was analysed by least squares regression methods. Results A total of 20 floating cages released nutrients into waterbodies at an average rate of 236.27±60.44 kg/cycle for C, 84.52±20.86 kg/cycle for N and 8.70±3.63 kg/cycle for P. On average, fish production for each floating cage (±SD) was 1226±282 kg wet weight/cycle, and the net fish yield was 12.63±2.82 kg/m 3/cycle. Survival rates ranged from 86.33 to 95.27%/cycle. The production cycles varied from 160 to 175 days with feed conversion ratios between 1.60 and 1.75, feed conversion efficiencies were between 0.58 and 0.63. The production parameters that had strong relationships with the net fish yield were feed supply ( r 2=0.960), stocking rates ( r 2=0.924) and feeding rates ( r 2=0.961). In contrast, the length of the production cycle was not strongly related to the net fish yield ( r 2=0.187). Conclusion Nutrient loading from the supplied feed was greater than that from the harvested fish, juvenile fish and dead fish. Increasing the net fish yield in floating cages was better predicted by the stocking densities and feeding levels than by the other factors.


Assuntos
Aquicultura , Lagos , Animais , Feminino , Peixes , Indonésia , Masculino , Nutrientes
14.
Dis Aquat Organ ; 146: 117-128, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34617517

RESUMO

Quorum sensing (QS) is a type of cell to cell communication in bacteria that can also regulate the virulence potential in pathogenic strains. Hence, QS disruption, i.e. the quorum quenching (QQ) mechanism, is presently being explored as a novel bio-control strategy to counter bacterial infections. In the present study, we characterized the QQ ability of Bacillus spp. strains to reduce the expression of some virulence factors of a shrimp pathogen, Vibrio harveyi. We screened a total of 118 spore-forming bacterial isolates from aquaculture ponds and mangrove soil for their ability to degrade the synthetic N-acyl-homoserine lactones (AHLs) C4-HSL, C6-HSL, C8-HSL, and C10-HSL. We then selected the top 17 isolates with high AHL-degradation ability for further study. Among them, B. subtilis MFB10, B. lentus MFB2, and B. firmus MFB7 had the highest ability for degradation. These 3 isolates suppressed the expression of virulence genes encoding protease, lipase, phospholipase, caseinase, chitinase, and gelatinase, and potentially inhibited the biofilm formation of V. harveyi MFB32. The reduction in expression of virulence genes like those coding for metalloprotease, serine protease, and haemolysin were confirmed by real-time PCR analysis. Moreover, in an in vivo challenge experiment, these Bacillus spp. protected Penaeus monodon post-larvae against V. harveyi MFB3 infection. Our results demonstrate the potential application of AHL-degrading Bacillus spp. as an alternative to antibiotics in shrimp hatcheries to control luminescent vibriosis. This novel bio-therapeutic method is a promising approach towards disease control in shrimp aquaculture.


Assuntos
Bacillus , Vibrioses , Animais , Aquicultura , Percepção de Quorum , Vibrio , Vibrioses/veterinária
15.
Vet Res ; 52(1): 131, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34649601

RESUMO

Piscine orthoreovirus-1 (PRV-1) is the causative agent of heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon (Salmo salar). However, it has been shown that PRV-1 variants differ in their ability to induce HSMI. The objective of this work was to identify the PRV-1 variants in Norwegian aquaculture and their geographical distribution. Sequencing and subsequent analysis of the five genomic segments (S1, S4, M2, L1 and L2) putatively linked to virulence, made out the basis of the study. Thirty-seven Norwegian PRV-1 isolates were sequenced, and they grouped into eight genogroups based on combinations of the five analyzed genomic segments. Two groups were defined as high-virulent and two low-virulent, based on comparison with PRV-1 reference isolates with known virulence. The remaining four groups were of unknown virulence. The geographic distribution indicated a higher frequency of the high-virulent isolates in the mid- and northern regions. The present study confirms circulation of both high- and low-virulent isolates of PRV-1 in farmed Atlantic salmon in Norway. To reduce the impact of PRV-1 related disease, detection and differentiation between high- and low-virulent genogroups of PRV-1 could be a targeted approach for reduction of high-virulent variants.


Assuntos
Doenças dos Peixes/virologia , Genótipo , Orthoreovirus/genética , Orthoreovirus/patogenicidade , Infecções por Reoviridae/veterinária , Salmo salar , Animais , Aquicultura , Noruega , Orthoreovirus/classificação , Infecções por Reoviridae/virologia , Virulência/genética
16.
Ecotoxicol Environ Saf ; 227: 112858, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34653940

RESUMO

Hundreds of tons of antibiotics are widely used in aquaculture to prevent microbial infections and promote fish growth. However, the overuse of antibiotics and chemical products can lead to the selection and spreading of antibiotic-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs), which are of great concern considering the threat to public health worldwide. Here, in-depth metagenome sequencing was performed to explore the environmental resistome and ARB distribution across farming stages in shrimp farms and examine anthropogenic effects in nearby coastal waters. A genome-centric analysis using a metagenome binning approach allowed us to accurately investigate the distribution of pathogens and ARG hosts in shrimp farms. The diversity of resistomes was higher in shrimp farms than in coastal waters, and the distribution of resistomes was dependent on the farming stage. In particular, the tetracycline resistance gene was found mainly at the early post-larval stage regardless of the farm. The metagenome-assembled genomes of Vibrio spp. were dominant at this stage and harbored tet34, which is known to confer resistance to oxytetracycline. In addition, opportunistic pathogens such as Francisella, Mycoplasma, Photobacterium, and Vibrio were found in abundance in shrimp farms, which had multiple virulence factors. This study highlights the increased resistance diversity and environmental selection of pathogens in shrimp farms. The use of environmental pollutants on farms may cause an increase in resistome diversity/abundance and the transmission of pathogens to the surrounding environment, which may pose future risks to public health and aquatic organisms.


Assuntos
Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Animais , Antibacterianos , Aquicultura , Fazendas , Genes Bacterianos , República da Coreia
17.
Front Cell Infect Microbiol ; 11: 752477, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660349

RESUMO

The prevalence of bacterial diseases and the application of probiotics to prevent them is a common practice in shrimp aquaculture. A wide range of bacterial species/strains is utilized in probiotic formulations, with proven beneficial effects. However, knowledge of their role in inhibiting the growth of a specific pathogen is restricted. In this study, we employed constraint-based genome-scale metabolic modeling approach to screen and identify the beneficial bacteria capable of limiting the growth of V. harveyi, a common pathogen in shrimp culture. Genome-scale models were built for 194 species (including strains from the genera Bacillus, Lactobacillus, and Lactococcus and the pathogenic strain V. harveyi) to explore the metabolic potential of these strains under different nutrient conditions in a consortium. In silico-based phenotypic analysis on 193 paired models predicted six candidate strains with growth enhancement and pathogen suppression. Growth simulations reveal that mannitol and glucoronate environments mediate parasitic interactions in a pairwise community. Furthermore, in a mannitol environment, the shortlisted six strains were purely metabolite consumers without donating metabolites to V. harveyi. The production of acetate by the screened species in a paired community suggests the natural metabolic end product's role in limiting pathogen survival. Our study employing in silico approach successfully predicted three novel candidate strains for probiotic applications, namely, Bacillus sp 1 (identified as B. licheniformis in this study), Bacillus weihaiensis Alg07, and Lactobacillus lindneri TMW 1.1993. The study is the first to apply genomic-scale metabolic models for aquaculture applications to detect bacterial species limiting Vibrio harveyi growth.


Assuntos
Penaeidae , Probióticos , Vibrio , Animais , Aquicultura , Bacillus , Simulação por Computador , Lactobacillus , Vibrio/genética
18.
Dis Aquat Organ ; 146: 53-63, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34553693

RESUMO

The purpose of this study was to determine the phylogenetic relationships among the primary betanodavirus strains circulating in Tunisian coastal waters. A survey was conducted to investigate nodavirus infections at 15 European sea bass Dicentrarchus labrax and gilthead sea bream Sparus aurata farming sites located along the northern and eastern coasts of Tunisia. The primary objective of the study was to create epidemiological awareness of these infections by determining phylogenetic relationships between the main betanodavirus strains circulating during the period 2012-2019, using RNA1 and/or RNA2 genome segments. Approximately 40% (118 of 294) tissue pools tested were positive for betanodavirus. Positive pools were distributed across all of the sampling sites. While fish mortalities were always correlated with the presence of virus in sea bass, a severe outbreak was also identified in sea bream larvae in 2019. Phylogenetic analysis revealed that almost all Tunisian strains from both sea bass and sea bream irrespective of outbreaks clustered within the RGNNV genotype. It is noteworthy that samples collected during the 2019 outbreak from sea bream contained both RNA1 and RNA2 fragments belonging to the RGNNV and SJNNV genotype, respectively, an indication of viral genome reassortment. To our knowledge, this is the first report of reassortant betanodavirus in Tunisia.


Assuntos
Bass , Doenças dos Peixes , Nodaviridae , Infecções por Vírus de RNA , Dourada , Animais , Aquicultura , Doenças dos Peixes/epidemiologia , Genótipo , Nodaviridae/genética , Filogenia , Filogeografia , Infecções por Vírus de RNA/epidemiologia , Infecções por Vírus de RNA/veterinária
19.
Nature ; 597(7876): 360-365, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34526707

RESUMO

Fish and other aquatic foods (blue foods) present an opportunity for more sustainable diets1,2. Yet comprehensive comparison has been limited due to sparse inclusion of blue foods in environmental impact studies3,4 relative to the vast diversity of production5. Here we provide standardized estimates of greenhouse gas, nitrogen, phosphorus, freshwater and land stressors for species groups covering nearly three quarters of global production. We find that across all blue foods, farmed bivalves and seaweeds generate the lowest stressors. Capture fisheries predominantly generate greenhouse gas emissions, with small pelagic fishes generating lower emissions than all fed aquaculture, but flatfish and crustaceans generating the highest. Among farmed finfish and crustaceans, silver and bighead carps have the lowest greenhouse gas, nitrogen and phosphorus emissions, but highest water use, while farmed salmon and trout use the least land and water. Finally, we model intervention scenarios and find improving feed conversion ratios reduces stressors across all fed groups, increasing fish yield reduces land and water use by up to half, and optimizing gears reduces capture fishery emissions by more than half for some groups. Collectively, our analysis identifies high-performing blue foods, highlights opportunities to improve environmental performance, advances data-poor environmental assessments, and informs sustainable diets.


Assuntos
Aquicultura , Ecossistema , Monitoramento Ambiental , Alimentos Marinhos , Desenvolvimento Sustentável , Animais , Aquicultura/tendências , Mudança Climática , Dieta , Ecologia , Política Ambiental , Pesqueiros , Abastecimento de Alimentos/métodos , Gases de Efeito Estufa , Humanos , Moluscos , Nitrogênio , Fósforo , Alimentos Marinhos/provisão & distribuição , Alga Marinha , Desenvolvimento Sustentável/tendências
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