Saprolegnia species in Norwegian salmon hatcheries: field survey identifies S. diclina sub-clade IIIB as the dominating taxon

Thoen, Even; Vrålstad, Trude; Rolén, Elin; Kristensen, Ralf; Evensen, Øystein; Skaar, Ida

doi:10.3354/dao02863

Cited by 12 publications

(16 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…S. diclina subclade IIIB were recently reported as the dominating Saprolegnia taxon in Norwegian salmon hatcheries (Thoen et al . ). The impact of such pathogenic isolates should thus, if they were of vital importance for triggering of disease, have been reflected in reduced hatching rates, even if the exact impact could not be extracted and quantified.…”

Section: Discussionmentioning

confidence: 97%

“…Scientists have engaged broadly in the problem, both in exploring the general biology of the organism and in the development of strategies to help control the problems it constitutes. Aspects of morphology (Beakes 1982;Hatai, Willoughby & Beakes 1990), genetics (Dieguez-Uribeondo, Cerenius & S€ oderh€ all 1996;Torto-Alalibo et al 2005;Dieguez-Uribeondo et al 2007;Jiang et al 2013; Thoen et al 2015), pathology (Willoughby 1994;Hussein & Hatai 2002;Thoen et al 2011;Songe et al 2015) and immunology (Alvarez et al 1988(Alvarez et al , 1995Belmonte et al 2014) are described in the literature. Further, a number of prospective fungicides have been investigated for efficacy against saprolegniosis (Hussein et al 2000;Stueland, Heier & Skaar 2005;Ali et al 2014a,b;Warrilow et al 2014).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Factors influencing Saprolegnia spp. spore numbers in Norwegian salmon hatcheries

Thoen

Evensen

Skaar

2015

Journal of Fish Diseases

Self Cite

View full text Add to dashboard Cite

A quantitative survey of Saprolegnia spp. in the water systems of Norwegian salmon hatcheries was performed. Water samples from 14 salmon hatcheries distributed along the Norwegian coastline were collected during final incubation in the hatcheries. Samples of inlet and effluent water were analyzed to estimate Saprolegnia propagule numbers. Saprolegnia spores were found in all samples at variable abundance. Number of spores retrieved varied from 50 to 3200 L À1 in inlet water and from 30 to >5000 L À1 in effluent water. A significant elevation of spore levels in effluent water compared to inlet water was detected. The estimated spore levels were related to recorded managerial and environmental parameters, and the number of spores in inlet water and temperature was the factor having most influence on the spore concentration in the incubation units (effluent water). Further, the relative impact of spore concentration on hatching rates was investigated by correlation analysis. From this was found that even high spore counts did not impact significantly on hatching success.

show abstract

Section: Discussionmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

Factors influencing Saprolegnia spp. spore numbers in Norwegian salmon hatcheries

Thoen

Evensen

Skaar

2015

Journal of Fish Diseases

Self Cite

View full text Add to dashboard Cite

show abstract

“…Cultures held on PDA should also be passaged through fish or cell lines every few generations to maintain virulence (Songe et al, 2014). To isolate a wild strain, mycelia are scrapped off an infected fish and inoculated onto a PDA plate containing chloramphenicol at 50 mg/mL to inhibit contamination (e.g., Songe et al, 2014;Kalatehjari et al, 2015;Thoen et al, 2015); chloramphenicol should not be used to maintain the culture as it is fungistatic (Rooke and Shattock, 1983). The Saprolegnia mycelium should then be replated (typically 2e5 times), taking 5 mm dia.…”

Section: Source Culture and Infectionmentioning

confidence: 99%

Hook, Line and Infection

Stewart

Jackson

Barber

et al. 2017

Advances in Parasitology

View full text Add to dashboard Cite

The three-spined stickleback (Gasterosteus aculeatus) is a model organism with an extremely well-characterized ecology, evolutionary history, behavioural repertoire and parasitology that is coupled with published genomic data. These small temperate zone fish therefore provide an ideal experimental system to study common diseases of coldwater fish, including those of aquacultural importance. However, detailed information on the culture of stickleback parasites, the establishment and maintenance of infections and the quantification of host responses is scattered between primary and grey literature resources, some of which is not readily accessible. Our aim is to lay out a framework of techniques based on our experience to inform new and established laboratories about culture techniques and recent advances in the field. Here, essential knowledge on the biology, capture and laboratory maintenance of sticklebacks, and their commonly studied parasites is drawn together, highlighting recent advances in our understanding of the associated immune responses. In compiling this guide on the maintenance of sticklebacks and a range of common, taxonomically diverse parasites in the laboratory, we aim to engage a broader interdisciplinary community to consider this highly tractable model when addressing pressing questions in evolution, infection and aquaculture.

show abstract

“…Saprolegnia parasitica has frequently been isolated from diseased salmonids in Finland [1] and elsewhere [2][3][4][5]. It is considered as the most pathogenic oomycete for juvenile and adult salmonids, while other Saprolegnia species are more devastating for fish eggs and fry [6][7][8]. The infection can be seen on fish as greyish and whitish hyphae growing on the skin and gills.…”

Section: Introductionmentioning

confidence: 99%

Detection and Quantification of the Oomycete Saprolegnia parasitica in Aquaculture Environments

et al. 2022

View full text Add to dashboard Cite

Saprolegnia parasitica induces heavy mortality in aquaculture. The detection of S. parasitica is often time consuming and uncertain, making it difficult to manage the disease. We validated a previously published real-time quantitative PCR (qPCR) assay to confirm the presence of S. parasitica in fish and in water using environmental DNA (eDNA) quantification. Analytical sensitivity and specificity of the assay was assessed in silico, in vitro and the qPCR assay was compared with microbiological cultivation methods to detect and quantify S. parasitica in water samples from a controlled fish exposure experiment and from fish farms. Furthermore, we compared the use of an agar cultivation method and the qPCR assay to detect S. parasitica directly from mucus samples taken from the fish surface. The analytical sensitivity and specificity of the qPCR assay were high. The qPCR assay detected 100% of S. parasitica-positive water samples. In a field study, the qPCR assay and a microwell plate (MWP) enumeration method correlated significantly. Furthermore, the qPCR assay could be used to confirm the presence of S. parasitica in skin mucus. Thus, the qPCR assay could complement diagnostic methods in specifically detecting saprolegniosis in fish and used as a surveillance method for S. parasitica pathogen in aquaculture environments.

show abstract

Saprolegnia species in Norwegian salmon hatcheries: field survey identifies S. diclina sub-clade IIIB as the dominating taxon

Cited by 12 publications

References 26 publications

Factors influencing Saprolegnia spp. spore numbers in Norwegian salmon hatcheries

Factors influencing Saprolegnia spp. spore numbers in Norwegian salmon hatcheries

Hook, Line and Infection

Detection and Quantification of the Oomycete Saprolegnia parasitica in Aquaculture Environments

Contact Info

Product

Resources

About