Search results for "Salmo"
showing 10 items of 442 documents
Spatiotemporal Dispersal and Deposition of Fish Farm Wastes: A Model Study from Central Norway
2017
Abstract A spatially explicit coupled hydrodynamic-mass transport model system was used to simulate dispersal of particulate organic matter from Atlantic salmon (Salmo salar) farming in central Norway. Model setups of 32 m horizontal resolution were run for periods of up to 650 days for 3 sites of different oceanographic characteristics: one fjord location, one medium-exposed location influenced by fjord water and one coastal location. Records on feed used for each cage at each location were converted to feces released based on a published mass balance model. The results from the simulations were compared with scores from corresponding mandatory benthic surveys (MOM-B) of the sediment layer…
Short sea migration and precocious maturation in reared Atlantic salmon post-smolts in the northern Baltic Sea
2017
Abstract Atlantic salmon (Salmo salar L.) display significant variation in life history traits, including migration patterns and age at maturity. Hatchery rearing has been shown to affect the life history, and rearing-induced changes may include unfavourable consequences, e.g. shortened sea migration period and smaller size at maturity. We report on a new phenomenon of life history of reared Atlantic salmon in the Baltic Sea area: small-sized salmon returning to freshwater only a few months after release as smolts. These “one-sea-summer (1SS)” salmon were ca. 35 cm in length and weighed ca. 400 g, being clearly larger than smolts, but substantially smaller than one-sea-winter (1SW) salmon f…
Oxygen and carbon isoscapes for the Baltic Sea : Testing their applicability in fish migration studies
2017
Conventional tags applied to individuals have been used to investigate animal movement, but these methods require tagged individuals be recaptured. Maps of regional isotopic variability known as “isoscapes” offer potential for various applications in migration research without tagging wherein isotope values of tissues are compared to environmental isotope values. In this study, we present the spatial variability in oxygen (δ18OH2O) and dissolved inorganic carbon (δ13CDIC) isotope values of Baltic Sea water. We also provide an example of how these isoscapes can reveal locations of individual animal via spatial probability surface maps, using the high-resolution salmon otolith isotope data fr…
Influence of warming temperatures on coregonine embryogenesis within and among species
2021
The greatest response of lakes to climate change has been the increase in water temperatures on a global scale. The responses of many lake fishes to warming water temperatures are projected to be inadequate to counter the speed and magnitude of climate change, leaving some species vulnerable to decline and extinction. We experimentally evaluated the responses of embryos from a group of cold, stenothermic fishes (Salmonidae Coregoninae) - within conspecifics across lake systems, between congeners within the same lake system, and among congeners across lake systems - to a thermal gradient using an incubation method that enabled global comparisons. Study groups included cisco (Coregonus artedi…
Migration strategies of brown trout (Salmo trutta) in a subarctic river system as revealed by stable isotope analysis
2018
We estimated the proportions of anadromous and freshwater‐resident brown trout (Salmo trutta) in different parts of the subarctic River Näätämöjoki/Neidenelva system (Finland and Norway) using carbon, nitrogen and hydrogen stable isotope analyses of archived scales as identifiers of migration strategy. Our results showed that carbon stable isotope values were the best predictor of migration strategy. Most individuals fell into two clearly distinct groups representing anadromous (47%) or freshwater‐resident (42%) individuals, but some fish had intermediate carbon values suggesting repeated movement between freshwater and the sea. The proportion of anadromous individuals decreased steadily wi…
Species interactions, environmental gradients and body size shape population niche width
2021
1. Competition for shared resources is commonly assumed to restrict population-level niche width of coexisting species. However, the identity and abundance of coexisting species, the prevailing environmental conditions, and the individual body size may shape the effects of interspecific interactions on species’ niche width. 2. Here we study the effects of interspecific and intraspecific interactions, lake area and altitude, and fish body size on the trophic niche width and resource use of a generalist predator, the littoral-dwelling large, sparsely rakered morph of European whitefish (Coregonus lavaretus; hereafter LSR whitefish). We use stable isotope, diet and survey fishing data from 14 …
Genome-wide divergence patterns support fine-scaled genetic structuring associated with migration tendency in brown trout
2018
Brown trout (Salmo trutta) exhibit highly diverse life histories varying from resident, slow-growing, and early maturing to migratory, fast-growing, and late maturing, even within single watersheds. We sampled 11 locations within the transboundary Finnish–Russian River Koutajoki watershed to evaluate genomic differences among mainstem and headwater sites, of which some are isolated by migration barriers. Restriction site associated sequencing (RADSeq) revealed that the most headwater localities supported unique, isolated populations with generally lower heterozygosity compared with the mainstem populations. The sampled migratory adults in the three main stems showed signals of admixture de…
Typhoid Fever
2008
Typhoid fever continues to be a serious public health problem, with approximately 22. million cases and more than 200. 000 deaths globally. The disease is most often acquired by ingestion of food or water contaminated by the feces and less frequently by urine or vomitus of patients and carriers. Prolonged low-grade fever, headache, dry cough, alterations of bowel habits, coated tongue, and rose spots are the typical clinical features. Definitive diagnosis requires the isolation of Salmonella enterica serovar Typhi. Supportive serological tests are also used. First-choice antibiotic treatment includes fluoroquinolones or third-generation cephalosporins and reduces the mortality rate from 20%…
Protective Effect of Cactus Cladode Extracts on Peroxisomal Functions in Microglial BV-2 Cells Activated by Different Lipopolysaccharides
2017
International audience; In this study, we aimed to evaluate the antioxidant and anti-inflammatory properties of Opuntia ficus-indica cactus cladode extracts in microglia BV-2 cells. Inflammation associated with microglia activation in neuronal injury can be achieved by LPS exposure. Using four different structurally and biologically well-characterized LPS serotypes, we revealed a structure-related differential effect of LPS on fatty acid β-oxidation and antioxidant enzymes in peroxisomes: Escherichia coli-LPS decreased ACOX1 activity while Salmonella minnesota-LPS reduced only catalase activity. Different cactus cladode extracts showed an antioxidant effect through microglial catalase activ…
Replacement of fishmeal with corn gluten meal in feeds for juvenile rainbow trout (Oncorhynchus mykiss) does not affect oxygen consumption during for…
2017
Abstract We compared oxygen consumption (MO 2 , mg/kg/h) of c. 80 g rainbow trout ( Oncorhynchus mykiss ) in an intermittent-flow swim respirometer at 15 °C. Before the tests the fish were grown in flow through tanks (15 °C) with either fishmeal (FM) or corn gluten meal (CGM) based diets (c. 52% protein) for a period of 3–4.5 months. Ten individuals from both treatment groups were fasted for 48 h before the swim test, which consisted of 18 loops of 210 s over three different periods: acclimation period (6 loops at 0.5 body lengths per s, BL/s), exercise period (8 loops at increased speed from 1 to 2.5 BL/s with recovery loops at 0.5 BL/s), and a recovery period (four loops at 0.5 BL/s). We …