Search results for "salmon"
showing 10 items of 354 documents
Carbon, nitrogen and oxygen isotope fractionation during food cooking: Implications for the interpretation of the fossil human record.
2017
13 pages; International audience; ObjectivesStable isotope data provide insight into the reconstruction of ancient human diet. However, cooking may alter the original stable isotope compositions of food due to losses and modifications of biochemical and water components.MethodsTo address this issue, carbon, nitrogen and oxygen isotope ratios were measured on meat aliquots sampled from various animals such as pork, beef, duck and chicken, and also from the flesh of fishes such as salmon, European seabass, European pilchard, sole, gilt-head bream, and tuna. For each specimen, three pieces were cooked according to the three most commonly-known cooking practices: boiling, frying and roasting on…
Use of DNA barcoding in the assignment of commercially valuable fish species from Romania
2017
DNA barcoding is a molecular technique frequently used either for biodiversity monitoring and fish conservation or in the identification of the species of origin for raw and processed food from restaurants or fish markets. The most important aspect of this technique is that it works for all stages of life and can be used to distinguish between closely related taxa. Also, the technique has been used to unmask attempts of frauds in fish markets where more desirable and expensive fish are sometimes substituted with lower valued species. Our study aims to test the utility of the COI barcoding gene in the correct identification of several economically and ecologically valuable fish species, and …
Preliminary Study on the In vitro and In vivo Effects of Asparagopsis taxiformis Bioactive Phycoderivates on Teleosts
2016
Several compounds from marine organisms have been studied for their potential use in aquaculture. Among the red algae, Asparagopsis taxiformis is considered one of the most promising species for the production of bioactive metabolites with numerous proposed applications. Here, the in vitro antibacterial activity, the easy handling and the absence of adverse effects on marine fish species are reported. Depending on the seasonal period of sampling, ethanol extracts of A. taxiformis exhibited significantly different inhibitory activity against fish pathogenic bacteria. The extract obtained in late spring showed strong antibacterial activity against Aeromonas salmonicida subsp. salmonicida, Vib…
Northern European Salmo trutta (L.) populations are genetically divergent across geographical regions and environmental gradients
2020
The salmonid fish Brown trout is iconic as a model for the application of conservation genetics to understand and manage local interspecific variation. However, there is still scant information about relationships between local and large-scale population structure, and to what extent geographical and environmental variables are associated with barriers to gene flow. We used information from 3,782 mapped SNPs developed for the present study and conducted outlier tests and gene–environment association (GEA) analyses in order to examine drivers of population structure. Analyses comprised >2,600 fish from 72 riverine populations spanning a central part of the species' distribution in norther…
Learned parasite avoidance is driven by host personality and resistance to infection in a fish-trematode interaction
2016
Cognitive abilities related to the assessment of risk improve survival. While earlier studies have examined the ability of animals to learn to avoid predators, learned parasite avoidance has received little interest. In a series of behavioural trials with the trematode parasite Diplostomum pseudospathaceum , we asked whether sea trout ( Salmo trutta trutta ) hosts show associative learning in the context of parasitism and if so, whether learning capacity is related to the likelihood of infection mediated through host personality and resistance. We show that animals are capable of learning to avoid visual cues associated with the presence of parasites. However, avoidance behaviour ceased af…
Unravelling the scientific debate on how to address wolf-dog hybridization in Europe
2019
Anthropogenic hybridization is widely perceived as a threat to the conservation of biodiversity. Nevertheless, to date, relevant policy and management interventions are unresolved and highly convoluted. While this is due to the inherent complexity of the issue, we hereby hypothesize that a lack of agreement concerning management goals and approaches, within the scientific community, may explain the lack of social awareness on this phenomenon, and the absence of effective pressure on decision-makers. By focusing on wolf x dog hybridization in Europe, we hereby (a) assess the state of the art of issues on wolf x dog hybridization within the scientific community, (b) assess the conceptual base…
Infectivity of trematode eye flukes in farmed salmonid fish — Effects of parasite and host origins
2009
Abstract Parasites cause significant economic losses in fish farming, and knowledge of the mechanisms underlying their effects on hosts is an essential prerequisite of preventative procedures for the parasite problem in hatcheries. One such mechanism is local adaptation of parasites, which should lead to higher infectivity of parasites in sympatric host–parasite combinations compared to corresponding allopatric combinations. In this study, we investigated the infectivity of two ubiquitous species of trematode eye flukes, Diplostomum sp. and Tylodelphus clavata, in their farmed salmonid fish hosts with respect to origin of the parasite and the host. First, we exposed two anadromous and one l…
Migratory passage structures at hydropower plants as potential physiological and behavioural selective agents
2019
Anthropogenic activities affect fish populations worldwide. River dams have profound impacts on ecosystems by changing habitats and hindering migration. In an effort to counteract such effects, a range of mitigation measures have been installed at hydroelectric power plants. However, not all individuals in a population use these measures, potentially creating strong selection processes at hydroelectric power plants. This may be especially true during migration; fish can get heavily delayed or pass through a hydropower turbine, thus facing increased mortality compared with those using a safe bypass route. In this study, we quantify migration route choices of descending wild passive integrate…
Synthesis of habitat restoration impacts on young-of-the-year salmonids in boreal rivers
2019
River restoration offers the potential to enhance biological integrity, often measured as fish population changes. We used a meta-analytical approach to synthesize density responses to in-stream habitat restoration by young-of-the year (YOY) brown trout and Atlantic salmon in 28 rivers (overall 32 restoration projects) in Finland. We also examined which local and watershed-scale factors most influenced restoration success. Finally, we conducted an expert survey to obtain an independent estimate of a sufficient density enhancement for restoration to be considered successful. Despite strong context-dependency, habitat restoration had an overall positive effect on YOY salmonid density. When co…
Resource polymorphism in European whitefish: Analysis of fatty acid profiles provides more detailed evidence than traditional methods alone
2019
Published version, licensed CC BY-NC-ND 4.0. , available at: http://dx.doi.org/10.1371/journal.pone.0221338 Resource polymorphism—whereby ancestral generalist populations give rise to several specialised morphs along a resource gradient—is common where species colonise newly formed ecosystems. This phenomenon is particularly well documented in freshwater fish populations inhabiting postglacial lakes formed at the end of the last ice age. However, knowledge on how such differential exploitation of resources across contrasting habitats might be reflected in the biochemical compositions of diverging populations is still limited, though such patterns might be expected. Here, we aimed to assess …