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Supplementary materials for Loss of Fshr prevents testicular maturation in Atlantic salmon (Salmo salar L.).
No full textSupplementary materials for "Loss of Fshr prevents testicular maturation in Atlantic salmon (Salmo salar L.)." published in Endocrinology, an Oxford academic journal
https://doi.org/10.1210/endocr/bqae01
Numerical models and long term monitoring - How can numerical models be used to support in situ sampling and survey design for long term hydrographic monitoring in standard sections?
Get PDFAs a part of regular monitoring of the marine environment, IMR conducts 10 fixed transects on a multiannual basis during which hydrographical, chemical and plankton data are collected at the same positions several times a year. The transect data sets, which in some cases span up to seven decades, have been vital to the understanding of long-term variability and trends in environmental and climate conditions. As an alternative approach to assemble physical data, numerical circulation models are widely used. There is a large variety of model data archives available, both internally at the IMR and from publicly open data portals, but it is difficult to consider the precision of the different models as they have different properties, resolution, coverage area etc. This report assesses how well existing model products developed and/or intensively used by the Oceanography and Climate Research Group can be utilised to assess and support the shipboard monitoring on the transects. Main focus is on TOPAZ, which is the only fully operational model with a model domain covering all the transects considered here. The results show that TOPAZ reproduces interannual variability and multiannual trends well. However, temperature, salinity and current velocity values, as well as seasonal variability and extreme conditions are less well represented. The operational (internal) Norkyst model show the best skill reproducing current velocities, but do not cover all transects. Using TOPAZ to assess how well the present sampling strategy captures the spatial variability in hydrographic variables suggests that the current sampling strategy is well designed in terms of the horizontal spacing of the fixed transects, although the sections in the northern Norwegian Sea and southern Barents Sea show a significant co-variability of Atlantic Water towards the Arctic Ocean. Assessing the impact of sampling frequency on long-term monitoring efforts in one of the transects, suggests a minimum sampling frequency of 3-4 transects per year to prevent loss of information relating to interannual variability and trends. We note, however, that a full assessment of the impact of sampling frequency on the transects must include also chemical and plankton observations and models, as well as the need of capturing short-term variations like the seasonal cycle.Numerical models and long term monitoring - How can numerical models be used to support in situ sampling and survey design for long term hydrographic monitoring in standard sections?publishedVersio
Risk assessment of grilled and barbecued food
Get PDFWhen grilling, more harmful substances can be formed than when frying in a pan. For most people, there is a low risk associated with eating grilled food. Grilling food at a high temperature and/or on a campfire, often, and eating a lot of it may damage one's health. Distance to the heat source, how early food is placed onto the grill, and the type of fuel used can affect the formation of harmful substances. It is known that heat treatment such as grilling and frying can give rise to unwanted toxic compounds in the food, so-called process-induced contaminants. Grilling is a common way of preparing food in Norway, and the grilling season has become longer. The food selection has become ever wider and sales of different types of grills are increasing. Many factors may thus have changed since VKM's previous assessment of health risks from the consumption of grilled food, which was published in 2007. To be able to give current and relevant advice to consumers and others who sell or offer grilled food, the Norwegian Food Safety Authority has asked VKM for updated knowledge about the formation of process-induced contaminants in different food products by different grilling methods, and an assessment of what risk this may pose. Main findings: Harmful substances can be formed at high cooking temperatures. When grilling, the temperature is higher and less controllable than when frying in a pan. There is good evidence that two groups of genotoxic and carcinogenic substances, heterocyclic amines (HAA) and polycyclic aromatic hydrocarbons (PAH), are formed in higher concentrations in grilled food than in fried food. VKM has assessed PAH, for which there are good studies of occurrence in barbecued food. PAHs are formed when fat burns after dripping from the food onto the heat source. PAHs can also be released from coal, briquettes and wood. The smoke with PAH settles on the food. The occurrence of PAH in grilled food varies greatly and depends on how the food is grilled. The concentration of PAH is highest in very well-done meat with a high fat content, such as pork ribs and hamburgers. The highest concentration of PAH was found in sausage grilled on a campfire. This is caused by unburnt fat or soot/smoke from the fire that stick to the sausage. By avoiding fat dripping directly onto the heat source, preventing smoke from coming into contact with the food, and not overcooking the food, the amount of PAH in grilled food can be reduced. When using charcoal, the PAH emission is higher immediately after lighting, and the amount of PAH in the food can be reduced by waiting sufficiently long before start grilling. It is not the number of times you grill that is a critical factor, but how. A "worst-case" scenario shows that the annual consumption of more than 15-25 meals that have been grilled in a way that produces a high PAH incidence may provide too low margin of exposure* for the risk to be low. If, on the other hand, you prefer lean barbecue food that is not overcooked, then you can eat it more than 100 times a year according to our calculations and still have a high enough margin of exposure. * Margin of exposure is the ratio between the lowest dose (reference point) that causes increased cancer in experimental animals and the calculated intake. Exposure margin below 10,000 is considered a public health concern. Norsk: Ved grilling kan det dannes flere helseskadelige stoffer enn ved steking i panne. For de fleste er det lav risiko knyttet til å spise grillmat.Risk assessment of grilled and barbecued foodpublishedVersionacceptedVersionacceptedVersio
Annual report on health monitoring of wild anadromous salmonids in Norway 2023 - Screening of Atlantic salmon postsmolts from Boknafjorden and Hardangerfjorden and sea trout from Hitra for pathogen infections
Get PDFThe Institute of Marine Research has investigated the prevalence of infectious salmon anemia virus (ISAV), salmonid alphavirus (SAV, PD virus), piscine orthoreovirus 1 (PRV-1), piscine myocarditis virus (PMCV) and bacterial kidney disease (BKD) infections in wild postsmolt Atlantic salmon and sea trout caught in 2023 in three aquaculture production areas (PO2, 3 and 6). The fish were collected as part of the national monitoring program for salmon lice. The postsmolts were taken in outer parts of Boknafjord (N = 50) and Hardangerfjord (N = 50) by trawling in the period May-June. The sea trout was caught using gillnet and fish trap in Hitra area in June. Low concentrations of SAV-RNA were detected in two post smolts from the Boknafjord and one post smolt from the Hardangerfjord. ISAV was detected in one fish from Boknafjorden, one post smolt from Hardangerfjorden and one sea trout from Hitra. PRV1 was detected in 6 post smolts, 5 from Boknafjorden and one from Hardangerfjorden. Low concentrations of PMCV were detected in 9 fish. The PMCV-positive postsmolts were collected from both fjords. There was also one PMCV-positive sea trout from Hitra. Virus-positive fish had high Ct-values (34-40) and these values represent probably weak or false positive results. Renibacterium salmoninarum (causative agent of BKD) was not detected in any postsmolt or sea trout. The results in the current report showed that postsmolt and sea trout from fjords had a very low occurance of pathogen infections, which is common in Norwegian aquaculture. These findings complement and confirm our previously reported data and may indicate that the prevalence of pathogen infections in wild salmon post-smolt and sea trout is not significantly affected by the occurrence of these infections in fish farming.Annual report on health monitoring of wild anadromous salmonids in Norway 2023 - Screening of Atlantic salmon postsmolts from Boknafjorden and Hardangerfjorden and sea trout from Hitra for pathogen infectionspublishedVersio
Scrutinizing the current management units of the greater argentine in the light of genetic structure
No full textDataset for "Scrutinizing the current management units of the greater argentine in the light of genetic structure" published in ICES Journal of Marine Science, an Oxford journal.
The information deposited here consists of two excel files:
1. Greater argentine_SNP markers.xlsx. This file contains two spreadsheets:
a. Greater argentine_Potential SNPs: A set of 128 potential SNPs were identified for greater argentine. SNP identification together with flanking sequence is provided for each marker. The SNP to be genotyped is identified within brackets. Putative SNPs in the flanking regions are depicted using the IUPAC ambiguity codes.
b. SNPs distribution in multiplex: Primers were developed for 100 of the potential SNPs and arrays were distributed into four multiplexes coded as W1, W2, W3 and W4.
2. Greater argentine_Raw SNP data.xlsx. This file contains the genotypic data for 1166 individuals typed at 88 SNP loci. Information consists of: Individual identification (ID), Sample (geographic sampling site), ICES stock and genotype data
Plasticity and Evolution in Atlantic Cod Populations during Climate Change
Get PDFIt is increasingly recognised that ecology and evolution may interact on contemporary time scales and result in ongoing eco-evolutionary dynamics at population- community- and ecosystem levels. Therefore, an eco-evolutionary perspective is needed to better understand how fish populations may respond to ongoing and future climate change. This chapter highlights research on the impact of climate warming on population dynamics, life history and behaviour of Atlantic cod (Gadus morhua), specifically making the case of integrating ecological and evolutionary perspectives for understanding local adaptations and broader responses to climate change. The chapter focuses particularly on the interactions between genotypes and the environment, a reflection of phenotypic plasticity that can be graphically described as a reaction norm. With some exceptions, fish tend to be highly plastic, meaning that the phenotype being expressed by an individual will depend on the environment that it experiences during its lifetime, and potentially that experienced by its parents. Understanding the mechanisms and constraints related to such plasticity is therefore relevant for studies on the effects of climate change.acceptedVersio
A genetic cline shapes population structure of the round sardinella along its West African distribution
Get PDFSmall pelagic fish play an important role in marine trophic webs and human food security. Among those, Sardinella aurita represents an extremely valuable resource in West Africa, where it is assumed to conform a transboundary stock. During the last decade, quantitative stock assessment has not been possible in NW African waters due to the limitation of the indices used; however, a critical biomass decline has been observed, and the stock is considered overexploited. In order to delineate the population structure of the species in West Africa, twelve microsatellites were developed ad hoc and genotyped on some 1300 individuals collected from Morocco to Angola. The significant differentiation detected between the northernmost samples (Morocco to Guinea) and the southernmost ones (Liberia to Angola) was due to one candidate locus to positive selection. The signal of this locus resided uniquely in the frequency of allele SauMS002_131, which displayed a remarkable latitudinal cline. Allele frequency, starting around 47%–63% in Moroccan-Guinean waters and dropping to 0% off Gabon and southwards, accounts for the North–South declining trend and can be used as a meaningful tool to assist population structure outline for this species in West Africa for management purposes in order to ensure sustainable regionally shared fisheries.publishedVersio
Spatial distribution, morphology, and risk assessment of microplastics in sediment from the Pearl River Estuary, China
Get PDFMicroplastics (MPs) (64.12 %) of detected MPs were <0.85 mm and primarily consisted of pellets (36.84 %) and fragments (29.65 %). Three polymer types of MPs were identified by Fourier Transform Infrared Spectroscopy (FT-IR) including polyethylene (PE), polyethylene terephthalate (PET), and polypropylene (PP). Polyurethane (PU) sponge was reported for the first time in this study area. Observations of the surface morphology of typical MPs using Scanning Electron Microscopy (SEM) showed that all MPs exhibited varying degrees of erosion, characterized by cracks, folds, and bumpy structures. Based on type and quantity of MPs and the polymers identified, we assessed and classified the risk of MP contamination in PRE sediment as category III, indicating severe ecosystem contamination. Our results may serve as an effective model for other estuaries facing similar pollution regimes and provides valuable information for marine sediment risk assessment.publishedVersio
From fringe to basin: unravelling the survival strategies of Calanus hyperboreus and C. glacialis in the Arctic Ocean
Get PDFThe large calanoids Calanus hyperboreus and C. glacialis dominate the zooplankton biomass in the central Arctic Ocean (CAO), but the absence of early life stages has raised speculation whether they complete their life cycle there, or whether they represent expatriates advected from adjacent regions. Our study, conducted across 2 transects of the CAO during fall 2011, focused on the distribution, stage composition, dry weight, individual lipid content, and egg production of these species. Although reproductive activity and early developmental stages were observed only on the fringes of the deep basins, late-stage copepodite and adult female abundances remained steady across the study area for C. glacialis and increased away from the shelves for C. hyperboreus. We found no decline in lipid content or dry weight in adult C. glacialis away from productive regions and only a minor reduction in adult C. hyperboreus. However, the lipid content and dry weight in C5 copepodites significantly decreased away from the shelf break, particularly in C. hyperboreus. This suggests that although early life stages struggle to survive in the resource-limited conditions of the deep CAO and even subadults remain vulnerable to starvation, adults have the resilience to survive long enough to be eventually transported by ocean currents to more favourable regions for reproduction. As such, we suggest that both species of Calanus are neither ‘residents’ nor ‘expatriates’ in the Arctic basins, but rather ontogenetic migrants that take advantage of different habitats within the Arctic Ocean to maximise their survival and reproductive success.publishedVersio
Bycatch of northern fulmar (Fulmarus glacialis) in Norwegian longline fisheries: Assessing spatiotemporal variations in scale and risk to improve management
Get PDFSeabirds are vulnerable to bycatch in longline fisheries but for most species the impacts are largely unknown. To address this knowledge gap, studies can estimate bycatch directly using observations or calculate the theoretical risk of bycatch using overlap indexes. Here we quantify the scale and risk of bycatch of northern fulmar (Fulmarus glacialis) in the Norwegian offshore longline fishery using a ten-year time series of bycatch observations from a reference fleet programme, and large-scale datasets of fishing activity and northern fulmar distribution. We estimated an average of 0.01 (95 % CI: 0.008–0.03) northern fulmars bycaught per 1000 hooks, which results in a highly varying estimated annual bycatch of between 51 and 16242 (95 % CI) northern fulmars per year, with the largest hotspot in the Norwegian Sea during June-August. We compared these estimates with overlap indexes calculated for northern fulmars and the same fishing activity. This pinpointed the highest risk of bycatch within the breeding season, where fishing activity increased in the waters around the largest cluster of breeding colonies in the northeast Atlantic. Strong correlations between estimated bycatch and calculated overlap indexes validate overlap indexes as an indirect evaluation of risk and strengthen evidence for management decisions based on the spatial and temporal trends identified in our analyses.Bycatch of northern fulmar (Fulmarus glacialis) in Norwegian longline fisheries: Assessing spatiotemporal variations in scale and risk to improve managementacceptedVersionpublishedVersio