Correction: The effect of exposure to farmed salmon on piscine orthoreovirus infection and fitness in wild Pacific salmon in British Columbia, Canada.

[This corrects the article DOI: 10.1371/journal.pone.0188793.].

Correction: The effect of exposure to farmed salmon on piscine orthoreovirus infection and fitness in wild Pacific salmon in British Columbia, Canada.

[This corrects the article DOI: 10.1371/journal.pone.0188793.].

The effect of exposure to farmed salmon on piscine orthoreovirus infection and fitness in wild Pacific salmon in British Columbia, Canada.

The disease Heart and Skeletal Muscle Inflammation (HSMI) is causing substantial economic losses to the Norwegian salmon farming industry where the causative agent, piscine orthoreovirus (PRV), is reportedly spreading from farmed to wild Atlantic salmon (Salmo salar) with as yet undetermined impacts. To assess if PRV infection is epidemiologically linked between wild and farmed salmon in the eastern Pacific, wild Pacific salmon (Oncorhynchus sp.) from regions designated as high or low exposure to salmon farms and farmed Atlantic salmon reared in British Columbia (BC) were tested for PRV. The proportion of PRV infection in wild fish was related to exposure to salmon farms (p = 0.0097). PRV was detected in: 95% of farmed Atlantic salmon, 37-45% of wild salmon from regions highly exposed to salmon farms and 5% of wild salmon from the regions furthest from salmon farms. The proportion of PRV infection was also significantly lower (p = 0.0008) where wild salmon had been challenged by an arduous return migration into high-elevation spawning habitat. Inter-annual PRV infection declined in both wild and farmed salmon from 2012-2013 (p ≤ 0.002). These results suggest that PRV transfer is occurring from farmed Atlantic salmon to wild Pacific salmon, that infection in farmed salmon may be influencing infection rates in wild salmon, and that this may pose a risk of reduced fitness in wild salmon impacting their survival and reproduction.

Discovery of variant infectious salmon anaemia virus (ISAV) of European genotype in British Columbia, Canada.

BACKGROUND: Infectious salmon anaemia (ISA) virus (ISAV) belongs to the genus Isavirus, family Orthomyxoviridae. ISAV occurs in two basic genotypes, North American and European. The European genotype is more widespread and shows greater genetic variation and greater virulence variation than the North American genotype. To date, all of the ISAV isolates from the clinical disease, ISA, have had deletions in the highly polymorphic region (HPR) on ISAV segment 6 (ISAV-HPRΔ) relative to ISAV-HPR0, named numerically from ISAV-HPR1 to over ISAV-HPR30. ISA outbreaks have only been reported in farmed Atlantic salmon, although ISAV has been detected by RT-PCR in wild fish. It is recognized that asymptomatically ISAV-infected fish exist. There is no universally accepted ISAV RT-qPCR TaqMan® assay. Most diagnostic laboratories use the primer-probe set targeting a 104 bp-fragment on ISAV segment 8. Some laboratories and researchers have found a primer-probe set targeting ISAV segment 7 to be more sensitive. Other researchers have published different ISAV segment 8 primer-probe sets that are highly sensitive. METHODS: In this study, we tested 1,106 fish tissue samples collected from (i) market-bought farmed salmonids and (ii) wild salmon from throughout British Columbia (BC), Canada, for ISAV using real time RT-qPCR targeting segment 8 and/or conventional RT-PCR with segment 8 primers and segment 6 HPR primers, and by virus isolation attempts using Salmon head kidney (SHK-1 and ASK-2) cell line monolayers. The sequences from the conventional PCR products were compared by multiple alignment and phylogenetic analyses. RESULTS: Seventy-nine samples were "non-negative" with at least one of these tests in one or more replicates. The ISAV segment 6 HPR sequences from the PCR products matched ISAV variants, HPR5 on 29 samples, one sample had both HPR5 and HPR7b and one matched HPR0. All sequences were of European genotype. In addition, alignment of sequences of the conventional PCR product segment 8 showed they had a single nucleotide mutation in the region of the probe sequence and a 9-nucleotide overlap with the reverse primer sequence of the real time RT-qPCR assay. None of the classical ISAV segment 8 sequences in the GenBank have this mutation in the probe-binding site of the assay, suggesting the presence of a novel ISAV variant in BC. A phylogenetic tree of these sequences showed that some ISAV sequences diverted early from the classical European genotype sequences, while others have evolved separately. All virus isolation attempts on the samples were negative, and thus the samples were considered "negative" in terms of the threshold trigger set for Canadian federal regulatory action; i.e., successful virus isolation in cell culture. CONCLUSIONS: This is the first published report of the detection of ISAV sequences in fish from British Columbia, Canada. The sequences detected, both of ISAV-HPRΔ and ISAV-HPR0 are of European genotype. These sequences are different from the classical ISAV segment 8 sequences, and this difference suggests the presence of a new ISAV variant of European genotype in BC. Our results further suggest that ISAV-HPRΔ strains can be present without clinical disease in farmed fish and without being detected by virus isolation using fish cell lines.

Phytotoxicity of GF-120 NF Naturalyte fruit fly bait carrier on sweet cherry (Prunus avium L.) foliage.

BACKGROUND: Six sweet cherry (Prunus avium L.) cultivars were tested with GF-120 with spinosad (0.2 g L(-1) spinosad bait) or without it (blank bait) to understand leaf phytotoxicity observed in the field. RESULTS: Spinosad bait and blank bait did not differ significantly with respect to damage observed. Leaf damage was found almost exclusively at the abaxial (lower) surfaces with the doses (0, 17, 20, 25 or 40%) and cultivars tested. The effects of the blank bait on abaxial surfaces increased from 24 to 168 h, and with dose, in terms of the proportion of droplets (0.00, 0.42, 0.52, 0.75 or 0.94) and area (0.0, 18.7, 23.5, 40.5 or 91.6 mm) burned. In addition, chlorophyll was reduced with increasing dose on abaxial surfaces (SPAD = 44.6, 36.1, 34.1, 31.0, 21.5), but not on adaxial (upper) surfaces (SPAD = 44.6, 44.2, 44.0, 44.8, 44.4). The chlorophyll level in undamaged leaves (adaxial surfaces) differed by cultivar. Cherry leaves were less damaged by a 20% bait application in June (0.26) than in July (0.46) and August (0.50). Incidental insect leaf feeding at bait locations occurred at a low rate and was highest on abaxial bait surfaces. CONCLUSIONS: Applying GF-120 to the adaxial leaf surface, or at doses of

Microbial communities in wetlands of the Athabasca oil sands: genetic and metabolic characterization.

Naphthenic acids are a complex family of naturally occurring cyclic and acyclic carboxylic acids that are present in the acidic fraction of petroleum. Naphthenic acids are acutely toxic to aquatic organisms. Previous studies showed that wetland sediments exposed to oil sands process water containing naphthenic acids had higher rates of naphthenic acid degradation in vitro compared with unexposed wetlands. In this study we compare the microbial community structures in sediments from wetlands exposed to different amounts of oil sands process water using BIOLOG, phospholipid fatty acid analysis and denaturing gradient gel electrophoresis of total bacterial DNA. Community profiles were compared using cluster analysis. BIOLOG profiles were primarily influenced by seasonal trends rather than naphthenic acids content. In contrast, phospholipid fatty acid analysis comparisons clustered communities that had higher levels of residual oil, although this association was not strong. In contrast, cluster diagrams produced from the denaturing gradient gel electrophoresis data clearly separated bacterial communities according to naphthenic acids concentrations, indicating that naphthenic acids content was a major influence on the composition of the bacterial community. In addition, denaturing gradient gel electrophoresis profiles indicated that naphthenic acids-exposed bacterial communities were homogeneous on a scale of meters, whereas unexposed (off-site) wetlands were less homogeneous.