Acute Hepatopancreatic Necrosis Disease (AHPND): Virulence, Pathogenesis and Mitigation Strategies in Shrimp Aquaculture

Shrimp, as a high-protein animal food commodity, are one of the fastest growing food producing sectors in the world. It has emerged as a highly traded seafood product, currently exceeding 8 MT of high value. However, disease outbreaks, which are considered as the primary cause of production loss in shrimp farming, have moved to the forefront in recent years and brought socio-economic and environmental unsustainability to the shrimp aquaculture industry. Acute hepatopancreatic necrosis disease (AHPND), caused by Vibrio spp., is a relatively new farmed penaeid shrimp bacterial disease. The shrimp production in AHPND affected regions has dropped to ~60%, and the disease has caused a global loss of USD 43 billion to the shrimp farming industry. The conventional approaches, such as antibiotics and disinfectants, often applied for the mitigation or cure of AHPND, have had limited success. Additionally, their usage has been associated with alteration of host gut microbiota and immunity and development of antibiotic resistance in bacterial pathogens. For example, the Mexico AHPND-causing V. parahaemolyticus strain (13-306D/4 and 13-511/A1) were reported to carry tetB gene coding for tetracycline resistance gene, and V. campbellii from China was found to carry multiple antibiotic resistance genes. As a consequence, there is an urgent need to thoroughly understand the virulence mechanism of AHPND-causing Vibrio spp. and develop novel management strategies to control AHPND in shrimp aquaculture, that will be crucially important to ensure food security in the future and offer economic stability to farmers. In this review, the most important findings of AHPND are highlighted, discussed and put in perspective, and some directions for future research are presented.

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Draft Genome Sequence of the Shrimp Pathogen Vibrio parahaemolyticus ST17.P5-S1, Isolated in Peninsular Malaysia

Microbiology Resource Announcements ◽

10.1128/mra.01053-18 ◽

2018 ◽

Vol 7 (11) ◽

Cited By ~ 2

Author(s):

Sridevi Devadas ◽

Subha Bhassu ◽

Tze Chiew Christie Soo ◽

Fatimah M. Yusoff ◽

Mohamed Shariff

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Vibrio Parahaemolyticus ◽

East Coast ◽

Draft Genome ◽

Antibiotic Resistance Genes ◽

Peninsular Malaysia ◽

Penaeus Vannamei ◽

Content Type ◽

Acute Hepatopancreatic Necrosis Disease

We sequenced the genome of Vibrio parahaemolyticus strain ST17.P5-S1, isolated from Penaeus vannamei cultured in the east coast of Peninsular Malaysia. The strain contains several antibiotic resistance genes and a plasmid encoding the Photorhabdus insect-related (Pir) toxin-like genes, pirAvp and pirBvp, associated with acute hepatopancreatic necrosis disease (AHPND).

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Identification and antibiotic resistance profiling of bacterial isolates from septicaemic soft-shelled turtles (Pelodiscus sinensis)

Veterinární Medicína ◽

10.17221/65/2016-vetmed ◽

2017 ◽

Vol 62 (No. 3) ◽

pp. 169-177 ◽

Cited By ~ 13

Author(s):

TH Chung ◽

SW Yi ◽

BS Kim ◽

WI Kim ◽

GW Shin

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Present Report ◽

Antibiotic Resistance Genes ◽

Tetracycline Resistance ◽

Edwardsiella Tarda ◽

Pelodiscus Sinensis ◽

Class 1 Integron ◽

Class 1 ◽

M 14

The present study sought to identify pathogens associated with septicaemia in the Chinese soft-shelled turtle (Pelodiscus sinensis) and to characterise antibiotic resistance in these pathogens. Twenty-three isolates recovered from the livers of diseased soft-shelled turtles were genetically identified as Aeromonas hydrophila (n = 8), A. veronii (n = 3), Citrobacter freundii (n = 4), Morganella morganii (n = 3), Edwardsiella tarda (n = 2), Wohlfahrtiimonas chitiniclastica (n = 1), Chryseobacterium sp. (n = 1), and Comamonas sp. (n = 1). Most isolates (n = 21) were resistant to ampicillin whereas a low percentage of isolates was susceptible to aminoglycosides (amikacin, gentamicin, and tobramycin). PCR assays and sequence analysis revealed the presence of the qnrS2 and blaTEM antibiotic resistance genes in all isolates. The blaDHA-1, blaCTX-M-14 and blaCMY-2 genes were harboured by 17.4% (n = 4), 13.5% (n = 3) and 8.7% (n = 2) of the strains, respectively. One or more tetracycline resistance genes were detected in 60.9% (n = 14) of the isolates. Four isolates (17.4%) harboured single or multiple class 1 integron cassettes. Collectively, a variety of bacterial pathogens were involved in the occurrence of septicaemia in Chinese soft-shelled turtles and most of the isolates had multi-antibiotic resistant phenotypes. To our knowledge, the present report is the first to identify W. chitiniclastica and Comamonas sp. as causes of septicaemia in soft-shelled turtles and the first to identify Aeromonas spp. with blaCTX-M-14 and blaDHA-1 resistance genes.

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Survey and Sequence Characterization of Bovine Mastitis-Associated Escherichia coli in Dairy Herds

Frontiers in Veterinary Science ◽

10.3389/fvets.2020.582297 ◽

2020 ◽

Vol 7 ◽

Author(s):

John I. Alawneh ◽

Ben Vezina ◽

Hena R. Ramay ◽

Hulayyil Al-Harbi ◽

Ameh S. James ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Bovine Mastitis ◽

Antibiotic Resistance Genes ◽

Tetracycline Resistance ◽

Sequence Type ◽

Genotypic Differences ◽

Beta Lactam ◽

Sequence Characterization ◽

E Coli

Escherichia coli is frequently associated with mastitis in cattle. “Pathogenic” and “commensal” isolates appear to be genetically similar. With a few exceptions, no notable genotypic differences have been found between commensal and mastitis-associated E. coli. In this study, 24 E. coli strains were isolated from dairy cows with clinical mastitis in three geographic regions of Australia (North Queensland, South Queensland, and Victoria), sequenced, then genomically surveyed. There was no observed relationship between sequence type (ST) and region (p = 0.51). The most common Multi Locus Sequence Type was ST10 (38%), then ST4429 (13%). Pangenomic analysis revealed a soft-core genome of 3,463 genes, including genes associated with antibiotic resistance, chemotaxis, motility, adhesion, biofilm formation, and pili. A total of 36 different plasmids were identified and generally found to have local distributions (p = 0.02). Only 2 plasmids contained antibiotic resistance genes, a p1303_5-like plasmid encoding multidrug-resistance (trimethoprim, quaternary ammonium, beta-lactam, streptomycin, sulfonamide, and kanamycin) from two North Queensland isolates on the same farm, while three Victorian isolates from the same farm contained a pCFSAN004177P_01-like plasmid encoding tetracycline-resistance. This pattern is consistent with a local spread of antibiotic resistance through plasmids of bovine mastitis cases. Notably, co-occurrence of plasmids containing virulence factors/antibiotic resistance with putative mobilization was rare, though the multidrug resistant p1303_5-like plasmid was predicted to be conjugative and is of some concern. This survey has provided greater understanding of antibiotic resistance within E. coli-associated bovine mastitis which will allow greater prediction and improved decision making in disease management.

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Intracellular versus extracellular antibiotic resistance genes in the environment: Prevalence, horizontal transfer, and mitigation strategies

Bioresource Technology ◽

10.1016/j.biortech.2020.124181 ◽

2021 ◽

Vol 319 ◽

pp. 124181

Author(s):

Ali Zarei-Baygi ◽

Adam L. Smith

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Horizontal Transfer ◽

Antibiotic Resistance Genes ◽

Mitigation Strategies

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The impacts of feeding milk with antibiotics on the fecal microbiome and antibiotic resistance genes in dairy calves

Canadian Journal of Animal Science ◽

10.1139/cjas-2018-0202 ◽

2020 ◽

Vol 100 (1) ◽

pp. 69-76

Author(s):

Xin Feng ◽

Heather M. Littier ◽

Katharine F. Knowlton ◽

Emily Garner ◽

Amy Pruden

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Dairy Calves ◽

Future Research ◽

Fecal Microbiome ◽

Cell Functions ◽

Whole Milk ◽

Waste Milk ◽

Negative Impacts

The effects of ingestion of antibiotics on the microbiome of the young calf are not well understood. The objective of this study was to evaluate the effect of feeding milk containing pirlimycin on the prevalence of antibiotic resistance genes in the fecal microbiome of dairy calves using a metagenomic approach. In this study calves were assigned to either pasteurized whole milk (control; n = 5) or pasteurized whole milk containing 0.2 mg L−1 of pirlimycin (treatment; n = 5). Fecal samples were collected on days 1, 42, and 84. Functional analysis of DNA via metagenomic rapid annotations using subsystems technology revealed that pirlimycin had no effects on abundance of sequences coding for different cell functions except in the “phage, prophage, and transposable elements” category. Evaluation of the major antibiotic resistance types in samples via annotation against the Comprehensive Antibiotic Resistance Database analysis showed no difference between the two groups. The results of this study will help assess the risk of use of antibiotics in animal agriculture and increase our understanding of how antibiotics present in waste milk affects both calves and their manure, and will lay the groundwork for future research on manure treatment or other strategies to minimize any negative impacts.

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Characterization of antibiotic resistance genes in the species of the rumen microbiota

Nature Communications ◽

10.1038/s41467-019-13118-0 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 9

Author(s):

Yasmin Neves Vieira Sabino ◽

Mateus Ferreira Santana ◽

Linda Boniface Oyama ◽

Fernanda Godoy Santos ◽

Ana Júlia Silva Moreira ◽

...

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Animal Health ◽

Antibiotic Resistance Genes ◽

Tetracycline Resistance ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Ruminal Bacteria ◽

Genes Encoding

AbstractInfections caused by multidrug resistant bacteria represent a therapeutic challenge both in clinical settings and in livestock production, but the prevalence of antibiotic resistance genes among the species of bacteria that colonize the gastrointestinal tract of ruminants is not well characterized. Here, we investigate the resistome of 435 ruminal microbial genomes in silico and confirm representative phenotypes in vitro. We find a high abundance of genes encoding tetracycline resistance and evidence that the tet(W) gene is under positive selective pressure. Our findings reveal that tet(W) is located in a novel integrative and conjugative element in several ruminal bacterial genomes. Analyses of rumen microbial metatranscriptomes confirm the expression of the most abundant antibiotic resistance genes. Our data provide insight into antibiotic resistange gene profiles of the main species of ruminal bacteria and reveal the potential role of mobile genetic elements in shaping the resistome of the rumen microbiome, with implications for human and animal health.

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Intra- and Interspecies Conjugal Transfer of Tn916-Like Elements from Lactococcus lactis In Vitro and In Vivo

Applied and Environmental Microbiology ◽

10.1128/aem.00470-09 ◽

2009 ◽

Vol 75 (19) ◽

pp. 6352-6360 ◽

Cited By ~ 25

Author(s):

Joanna Boguslawska ◽

Joanna Zycka-Krzesinska ◽

Andrea Wilcks ◽

Jacek Bardowski

Keyword(s):

Antibiotic Resistance ◽

Lactococcus Lactis ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Tetracycline Resistance ◽

Raw Milk ◽

M Gene ◽

Transfer Resistance

ABSTRACT Tetracycline-resistant Lactococcus lactis strains originally isolated from Polish raw milk were analyzed for the ability to transfer their antibiotic resistance genes in vitro, using filter mating experiments, and in vivo, using germfree rats. Four of six analyzed L. lactis isolates were able to transfer tetracycline resistance determinants in vitro to L. lactis Bu2-60, at frequencies ranging from 10−5 to 10−7 transconjugants per recipient. Three of these four strains could also transfer resistance in vitro to Enterococcus faecalis JH2-2, whereas no transfer to Bacillus subtilis YBE01, Pseudomonas putida KT2442, Agrobacterium tumefaciens UBAPF2, or Escherichia coli JE2571 was observed. Rats were initially inoculated with the recipient E. faecalis strain JH2-2, and after a week, the L. lactis IBB477 and IBB487 donor strains were introduced. The first transconjugants were detected in fecal samples 3 days after introduction of the donors. A subtherapeutic concentration of tetracycline did not have any significant effect on the number of transconjugants, but transconjugants were observed earlier in animals dosed with this antibiotic. Molecular analysis of in vivo transconjugants containing the tet(M) gene showed that this gene was identical to tet(M) localized on the conjugative transposon Tn916. Primer-specific PCR confirmed that the Tn916 transposon was complete in all analyzed transconjugants and donors. This is the first study showing in vivo transfer of a Tn916-like antibiotic resistance transposon from L. lactis to E. faecalis. These data suggest that in certain cases food lactococci might be involved in the spread of antibiotic resistance genes to other lactic acid bacteria.

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Incidence, Distribution, and Spread of Tetracycline Resistance Determinants and Integron-Associated Antibiotic Resistance Genes among Motile Aeromonads from a Fish Farming Environment

Applied and Environmental Microbiology ◽

10.1128/aem.67.12.5675-5682.2001 ◽

2001 ◽

Vol 67 (12) ◽

pp. 5675-5682 ◽

Cited By ~ 178

Author(s):

Anja S. Schmidt ◽

Morten S. Bruun ◽

Inger Dalsgaard ◽

Jens L. Larsen

Keyword(s):

Antibiotic Resistance ◽

Resistance Gene ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Tetracycline Resistance ◽

Class 1 Integron ◽

Gene Cassettes ◽

Class 1 Integrons ◽

Resistance Determinants ◽

Class 1

ABSTRACT A collection of 313 motile aeromonads isolated at Danish rainbow trout farms was analyzed to identify some of the genes involved in high levels of antimicrobial resistance found in a previous field trial (A. S. Schmidt, M. S. Bruun, I. Dalsgaard, K. Pedersen, and J. L. Larsen, Appl. Environ. Microbiol. 66:4908–4915, 2000), the predominant resistance phenotype (37%) being a combined oxytetracycline (OTC) and sulphadiazine/trimethoprim resistance. Combined sulphonamide/trimethoprim resistance (135 isolates) appeared closely related to the presence of a class 1 integron (141 strains). Among the isolates containing integrons, four different combinations of integrated resistance gene cassettes occurred, in all cases including a dihydrofolate reductase gene and a downstream aminoglycoside resistance insert (87 isolates) and occasionally an additional chloramphenicol resistance gene cassette (31 isolates). In addition, 23 isolates had “empty” integrons without inserted gene cassettes. As far as OTC resistance was concerned, only 66 (30%) out of 216 resistant aeromonads could be assigned to resistance determinant class A (19 isolates), D (n = 6), or E (n = 39); three isolates contained two tetracycline resistance determinants (AD, AE, and DE). Forty OTC-resistant isolates containing large plasmids were selected as donors in a conjugation assay, 27 of which also contained a class 1 integron. Out of 17 successful R-plasmid transfers to Escherichia coli recipients, the respective integrons were cotransferred along with the tetracycline resistance determinants in 15 matings. Transconjugants were predominantly tetApositive (10 of 17) and contained class 1 integrons with two or more inserted antibiotic resistance genes. While there appeared to be a positive correlation between conjugative R-plasmids andtetA among the OTC-resistant aeromonads, tetEand the unclassified OTC resistance genes as well as class 1 integrons were equally distributed among isolates with and without plasmids. These findings indicate the implication of other mechanisms of gene transfer besides plasmid transfer in the dissemination of antibiotic resistance among environmental motile aeromonads.

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Antibiotic Resistance Characteristics of Environmental Bacteria from an Oxytetracycline Production Wastewater Treatment Plant and the Receiving River

Applied and Environmental Microbiology ◽

10.1128/aem.02964-09 ◽

2010 ◽

Vol 76 (11) ◽

pp. 3444-3451 ◽

Cited By ~ 174

Author(s):

Dong Li ◽

Tao Yu ◽

Yu Zhang ◽

Min Yang ◽

Zhen Li ◽

...

Keyword(s):

Antibiotic Resistance ◽

River Water ◽

Resistance Genes ◽

Treatment Plant ◽

Antibiotic Resistance Genes ◽

Tetracycline Resistance ◽

Production Plant ◽

Bacterial Strains ◽

High Concentration ◽

Receiving River

ABSTRACT We characterized the bacterial populations in surface water receiving effluent from an oxytetracycline (OTC) production plant. Additional sampling sites included the receiving river water 5 km upstream and 20 km downstream from the discharge point. High levels of OTC were found in the wastewater (WW), and the antibiotic was still detectable in river water downstream (RWD), with undetectable levels in river water upstream (RWU). A total of 341 bacterial strains were isolated using nonselective media, with the majority being identified as Gammaproteobacteria. The MICs were determined for 10 antibiotics representing seven different classes of antibiotics, and the corresponding values were significantly higher for the WW and RWD isolates than for the RWU isolates. Almost all bacteria (97%) from the WW and RWD samples demonstrated multidrug-resistant (MDR) phenotypes, while in RWU samples, these were less frequent (28%). The WW and RWD isolates were analyzed for the presence of 23 tetracycline (tet) resistance genes. The majority of isolates (94.2% and 95.4% in WW and RWD, respectively) harbored the corresponding genes, with tet(A) being the most common (67.0%), followed by tet(W), tet(C), tet(J), tet(L), tet(D), tet(Y), and tet(K) (in the range between 21.0% and 40.6%). Class I integrons were detected in the majority of WW and RWD isolates (97.4% and 86.2%, respectively) but were not associated with the tet genes. We hypothesize that the strong selective pressure imposed by a high concentration of OTC contributes to the wide dissemination of tetracycline resistance genes and other antibiotic resistance genes, possibly through mobile genetic elements.

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