Environmental DNA from multiple pathogens is elevated near active Atlantic salmon farms

The spread of infection from reservoir host populations is a key mechanism for disease emergence and extinction risk and is a management concern for salmon aquaculture and fisheries. Using a quantitative environmental DNA methodology, we assessed pathogen environmental DNA in relation to salmon farms in coastal British Columbia, Canada, by testing for 39 species of salmon pathogens (viral, bacterial, and eukaryotic) in 134 marine environmental samples at 58 salmon farm sites (both active and inactive) over 3 years. Environmental DNA from 22 pathogen species was detected 496 times and species varied in their occurrence among years and sites, likely reflecting variation in environmental factors, other native host species, and strength of association with domesticated Atlantic salmon. Overall, we found that the probability of detecting pathogen environmental DNA (eDNA) was 2.72 (95% CI: 1.48, 5.02) times higher at active versus inactive salmon farm sites and 1.76 (95% CI: 1.28, 2.42) times higher per standard deviation increase in domesticated Atlantic salmon eDNA concentration at a site. If the distribution of pathogen eDNA accurately reflects the distribution of viable pathogens, our findings suggest that salmon farms serve as a potential reservoir for a number of infectious agents; thereby elevating the risk of exposure for wild salmon and other fish species that share the marine environment.

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First Report of Enteromyxum leei (Myxozoa) in the Black Sea in a Potential Reservoir Host Chromis chromis

Fish Pathology ◽

10.3147/jsfp.49.57 ◽

2014 ◽

Vol 49 (2) ◽

pp. 57-60 ◽

Cited By ~ 7

Author(s):

Ahmet ^|^Ouml;zer ◽

T^|^uuml;rkay ^|^Ouml;zt^|^uuml;rk ◽

Hakan ^|^Ouml;zkan ◽

Arzu ^|^Ccedil;am

Keyword(s):

Black Sea ◽

Reservoir Host ◽

The Black Sea ◽

First Report ◽

Potential Reservoir ◽

Enteromyxum Leei

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Detection of a global aquatic invasive amphibian, Xenopus laevis, using environmental DNA

Amphibia-Reptilia ◽

10.1163/15685381-00003036 ◽

2016 ◽

Vol 37 (1) ◽

pp. 131-136 ◽

Cited By ~ 13

Author(s):

Jean Secondi ◽

Tony Dejean ◽

Alice Valentini ◽

Benjamin Audebaud ◽

Claude Miaud

Keyword(s):

Invasive Species ◽

Xenopus Laevis ◽

Dna Amplification ◽

Control Program ◽

Environmental Dna ◽

Climatic Conditions ◽

Low Density ◽

African Species ◽

A Site ◽

And Control

Detection is crucial in the study and control of invasive species but it may be limited by methodological issues. In amphibians, classical survey techniques exhibit variable detection probability depending on species and are often constrained by climatic conditions often requiring several site visits. Furthermore, detection may be reduced at low density because probability capture (passive traps), or activity (acoustic surveys) drop. Such limits may impair the study of invasive species because low density is typical of the onset of colonisation on a site. In the last few years, environmental DNA (eDNA) methods have proved their ability to detect the presence of aquatic species. We developed here an eDNA method to detectXenopus laevisin ponds. This austral African species is now present worldwide because of its use in biology and as a pet. Populations have settled and expanded on several continents so that it is now considered as one of the major invasive amphibians in the World. We detected the presence ofX. laevisat density as low as 1 ind/100 m2and found a positive relationship between density in ponds and rate of DNA amplification. Results show that eDNA can be successfully applied to survey invasive populations ofX. laeviseven at low density in order to confirm suspected cases of introduction, delimit the expansion of a colonized range, or monitor the efficiency of a control program.

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Sheep as a Potential Reservoir Host for Schistosoma intercalatum

Journal of Parasitology ◽

10.2307/3279750 ◽

1978 ◽

Vol 64 (6) ◽

pp. 1136 ◽

Cited By ~ 2

Author(s):

Flemming Frandsen ◽

Jesper Monrad ◽

Niels Ornbjerg Christensen ◽

Peter Nansen

Keyword(s):

Reservoir Host ◽

Potential Reservoir ◽

Schistosoma Intercalatum

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Chemical composition and release rate of waste discharge from an Atlantic salmon farm with an evaluation of IMTA feasibility

Aquaculture Environment Interactions ◽

10.3354/aei00079 ◽

2013 ◽

Vol 4 (2) ◽

pp. 147-162 ◽

Cited By ~ 23

Author(s):

X Wang ◽

K Andresen ◽

A Handå ◽

B Jensen ◽

KI Reitan ◽

...

Keyword(s):

Chemical Composition ◽

Atlantic Salmon ◽

Release Rate ◽

Salmon Farm ◽

Waste Discharge

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WASTE LOADINGS FROM A FRESHWATER ATLANTIC SALMON FARM IN SCOTLAND

JAWRA Journal of the American Water Resources Association ◽

10.1111/j.1752-1688.1996.tb04070.x ◽

1996 ◽

Vol 32 (5) ◽

pp. 1017-1025 ◽

Cited By ~ 25

Author(s):

L. A. Kelly ◽

J. Stellwagen ◽

A. Bergheim

Keyword(s):

Atlantic Salmon ◽

Salmon Farm

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Rabies in the African Civet: An Incidental Host for Lyssaviruses?

Viruses ◽

10.3390/v12040368 ◽

2020 ◽

Vol 12 (4) ◽

pp. 368 ◽

Cited By ~ 1

Author(s):

Claude T. Sabeta ◽

Denise A. Marston ◽

Lorraine M. McElhinney ◽

Daniel L. Horton ◽

Baby M. N. Phahladira ◽

...

Keyword(s):

South Africa ◽

Reservoir Host ◽

Domestic Dogs ◽

Wildlife Species ◽

North East ◽

Virus Transfer ◽

Independent Cycle ◽

Potential Reservoir ◽

Continue Monitoring ◽

Incidental Host

In South Africa, canid rabies virus (RABV) infection is maintained in domestic and wildlife species. The identification of rabies in African civets raised the question of whether this wildlife carnivore is a potential reservoir host of RABVs of direct and ancestral dog origin (dog-maintained and dog-derived origins) with an independent cycle of transmission. Genetic analyses of African civet nucleoprotein sequences for 23 African civet RABVs and historically published sequences demonstrated that RABVs from African civets have two origins related to dog and mongoose rabies enzootics. The data support observations of the interaction of civets with domestic dogs and wildlife mongooses, mostly in Northern South Africa and North-East Zimbabwe. Within each host species clade, African civet RABVs group exclusively together, implying intra-species virus transfer occurs readily. The canid RABV clade appears to support virus transfer more readily between hosts than mongoose RABVs. Furthermore, these data probably indicate short transmission chains with conspecifics that may be related to transient rabies maintenance in African civets. Hence, it is important to continue monitoring the emergence of lyssaviruses in this host. Observations from this study are supported by ongoing and independent similar cases, in which bat-eared foxes and black-backed jackal species maintain independent rabies cycles of what were once dog-maintained RABVs.

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Field Studies Using a Recombinant Mycoinsecticide (Metarhizium anisopliae) Reveal that It Is Rhizosphere Competent

Applied and Environmental Microbiology ◽

10.1128/aem.68.12.6383-6387.2002 ◽

2002 ◽

Vol 68 (12) ◽

pp. 6383-6387 ◽

Cited By ~ 198

Author(s):

Gang Hu ◽

Raymond J. St. Leger

Keyword(s):

Metarhizium Anisopliae ◽

Fluorescent Protein ◽

Pathogenic Fungi ◽

Field Studies ◽

Field Conditions ◽

Research Station ◽

Potential Reservoir ◽

Green Fluorescent ◽

A Site ◽

Transgenic Strains

ABSTRACT In the summer of 2000, we released genetically altered insect-pathogenic fungi onto a plot of cabbages at a field site on the Upper Marlboro Research Station, Md. The transformed derivatives of Metarhizium anisopliae ARSEF 1080, designated GPMa and GMa, carried the Aequorea victoria green fluorescent protein (gfp) gene alone (GMa) or with additional protease genes (Pr1) (GPMa). The study (i) confirmed the utility of gfp for monitoring pathogen strains in field populations over time, (ii) demonstrated little dissemination of transgenic strains and produced no evidence of transmission by nontarget insects, (iii) found that recombinant fungi were genetically stable over 1 year under field conditions, and (iv) determined that deployment of the transgenic strains did not depress the culturable indigenous fungal microflora. The major point of the study was to monitor the fate (survivorship) of transformants under field conditions. In nonrhizosphere soil, the amount of GMa decreased from 105 propagules/g at depths of 0 to 2 cm to 103 propagules/g after several months. However, the densities of GMa remained at 105 propagules/g in the inner rhizosphere, demonstrating that rhizospheric soils are a potential reservoir for M. anisopliae. These results place a sharp focus on the biology of the soil/root interphase as a site where plants, insects, and pathogens interact to determine fungal biocontrol efficacy, cycling, and survival. However, the rhizospheric effect was less marked for GPMa, and overall it showed reduced persistence in soils than did GMa.

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