Browsing NORCE vitenarkiv by Author "Nilsen, Tom Ole"
Now showing items 1-14 of 14
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Effects of different photoperiod regimes on the smoltification and seawater adaptation of seawater-farmed rainbow trout (Oncorhynchus mykiss): Insights from Na+, K+-ATPase activity and transcription of osmoregulation and growth regulation genes
Morro, Bernat; Balseiro Vigo, Pablo; Albalat, Amaya; Pinto Pedrosa, Cindy; Mackenzie, Simon A.; Nakamura, Shu; Shimizu, Munetaka; Nilsen, Tom Ole; Sveier, Harald; Ebbesson, Lars O.E.; Handeland, Sigurd O (Journal article; Peer reviewed, 2019)Photoperiod is thought to be the main zeitgeber that induces smoltification in salmonids. However, its effects on the smoltification of rainbow trout (Oncorhynchus mykiss) are not fully understood and no published data ... -
Effects of temperature and photoperiod on rainbow trout (Oncorhynchus mykiss) smoltification and haematopoiesis
Morro, Bernat; Balseiro Vigo, Pablo; Albalat, Amaya; MacKenzie, Simon; Pedrosa, Cindy; Nilsen, Tom Ole; Suzuki, Shotaro; Shimizu, Munetaka; Sveier, Harald; Gorissen, Marnix; Ebbesson, Lars O.E.; Handeland, Sigurd O (Peer reviewed; Journal article, 2019)Highlights • nkaα1a, nkaα1b and nkcc1a provide relevant information that the NKA activity does not reflect. • While nkaα1a and nkcc1a transcription are mainly regulated by temperature, nkaα1b is regulated mainly by ... -
Exposure to cold temperatures differentially modulates neural plasticity and stress responses in post-smolt Atlantic salmon (Salmo salar)
Tang, Patrik Anthony; Stefansson, Sigurd Olav; Nilsen, Tom Ole; Gharbi, Naouel; Lai, Floriana; Tronci, Valentina; Vigo, Pablo Balseiro; Marnix, M.; Ebbesson, Lars O.E. (Peer reviewed; Journal article, 2022)The transfer success of farmed post-smolt Atlantic salmon (Salmo salar) to sea-cages rely on neural adaptions to promote stress resilience. As low temperatures impact physiology, this suggests that off-season transfer to ... -
Expression and localization of the aryl hydrocarbon receptors and cytochrome P450 1A during early development of Atlantic cod (Gadus morhua)
Aranguren Abadía, Libe; Donald, Carey; Eilertsen, Mariann; Gharbi, Naouel; Tronci, Valentina; Sørhus, Elin; Mayer, Philipp; Nilsen, Tom Ole; Meier, Sonnich; Goksøyr, Anders; Karlsen, Odd Andre (Peer reviewed; Journal article, 2020)The aryl hydrocarbon receptor (Ahr) is a ligand-activated transcription factor that mediates the toxicity of dioxins and dioxin-like compounds (DLCs) in vertebrates. Two clades of the Ahr family exist in teleosts (Ahr1 and ... -
Increased Thermal Challenges Differentially Modulate Neural Plasticity and Stress Responses in Post-Smolt Atlantic Salmon (Salmo salar)
Tang, Patrik Anthony; Gharbi, Naouel; Nilsen, Tom Ole; Gorissen, M.; Stefansson, Sigurd Olav; Ebbesson, Lars O.E. (Journal article; Peer reviewed, 2022)The successful transfer of farmed post-smolt Atlantic salmon (Salmo salar) depends on proper stress responses and cognitive functions during the early seawater (SW) phase. However, with increasing summer oceanic temperatures, ... -
Intact rather than total circulating insulin-like growth factor binding protein-1a is a negative indicator of growth in masu salmon
Kaneko, Nobuto; Nilsen, Tom Ole; Tanaka, Hanae; Hara, Akihiko; Shimizu, Munetaka (Peer reviewed; Journal article, 2020)Insulin-like growth factor binding protein (IGFBP)-1a is one of three major circulating forms in salmon and induced under catabolic conditions. However, there is currently no immunoassay available for this form because of ... -
Ion transporters and osmoregulation in the kidney of teleost fishes as a function of salinity
Takvam, Marius; Wood, Chris M.; Kryvi, Harald; Nilsen, Tom Ole (Peer reviewed; Journal article, 2021)Euryhaline teleosts exhibit major changes in renal function as they move between freshwater (FW) and seawater (SW) environments, thus tolerating large fluctuations in salinity. In FW, the kidney excretes large volumes of ... -
Molecular and physiological responses to long-term carbon dioxide exposure in Atlantic salmon (Salmo salar)
Mota, Vasco C.; Nilsen, Tom Ole; Gerwins, Jascha; Gallo, Michele; Kolarevic, Jelena; Krasnov, Aleksei; Terjesen, Bendik Fyhn (Peer reviewed; Journal article, 2019)Optimal water quality is vital for the growth of Atlantic salmon aquaculture production. Recent data showed that Atlantic salmon feed intake and growth reduce linearly with increasing water carbon dioxide (CO2) concentrations, ... -
New wine in old bottles: Modification of the Na+/K+-ATPase enzyme activity assay and its application in salmonid aquaculture
Takvam, Marius; Sundell, Kristina; Sundh, Henrik; Gharbi, Naouel; Kryvi, Harald; Nilsen, Tom Ole (Peer reviewed; Journal article, 2023)The Na+, K+ ATPase (NKA) enzyme is important to generate the transmembrane ion gradient in the gills, intestine, and kidneys, hence, is vital for secondary transport of fluids and different solutes in teleosts. Gill NKA ... -
Performance and welfare of Atlantic salmon, Salmo salar L. post-smolts in recirculating aquaculture systems: Importance of salinity and water velocity
Ytrestøyl, Trine; Takle, Harald Rune; Kolarevic, Jelena; Calabrese, Sara; Timmerhaus, Gerrit; Rosseland, Bjørn Olav; Teien, Hans-Christian; Nilsen, Tom Ole; Handeland, Sigurd O; Stefansson, Sigurd; Ebbesson, Lars; Terjesen, Bendik Fyhn (Journal article; Peer reviewed, 2020)Producing a larger post-smolt in recirculating aquaculture systems (RAS) could shorten the production time in sea cages and potentially reduce mortality. Knowledge of the biological requirements of post-smolts in ... -
Sulfate homeostasis in Atlantic salmon is associated with differential regulation of salmonid-specific paralogs in gill and kidney
Takvam, Marius; Denker, Elsa; Gharbi, Naouel; Kryvi, Harald; Nilsen, Tom Ole (Peer reviewed; Journal article, 2021)Sulfate (urn:x-wiley:2051817X:media:phy215059:phy215059-math-0001) regulation is challenging for euryhaline species as they deal with large fluctuations of urn:x-wiley:2051817X:media:phy215059:phy215059-math-0002 during ... -
Triploid Atlantic salmon and triploid Atlantic salmon × brown trout hybrids have better freshwater and early seawater growth than diploid counterparts
Fraser, Thomas; Lerøy, Hilde; Hansen, Tom Johnny; Skjæraasen, Jon Egil; Tronci, Valentina; Pinto Pedrosa, Cindy; Fjelldal, Per Gunnar; Nilsen, Tom Ole (Journal article; Peer reviewed, 2021)The use of reproductively sterile triploid salmonids would enhance the environmental sustainability of the aquaculture industry by preventing genetic exchange between escapees and wild conspecifics. To this end, we assessed ... -
Triploidy leads to a mismatch of smoltification biomarkers in the gill and differences in the optimal salinity for post-smolt growth in Atlantic salmon
de Fonseka, Raneesha; Fjelldal, Per Gunnar; Sambraus, Florian; Nilsen, Tom Ole; Remø, Sofie C.; Stien, Lars Helge; Reinardy, Helena; Madaro, Angelico; Hansen, Tom Johnny; Fraser, Thomas (Peer reviewed; Journal article, 2021)Sterile triploid Atlantic salmon (Salmo salar) show inconsistent seawater grow-out, but the reason why remains unclear. The purpose of this study was to determine the salinity optima of triploid post-smolts. Diploids and ... -
Validating timing of salmon smolt runs obtained by telemetry studies
Hulbak, Magnus Andre; Hanssen, Erlend Mjelde; Lennox, Robert; Salvanes, Anne Gro Vea; Barlaup, Bjørn Torgeir; Gharbi, Naouel; Nilsen, Tom Ole; Vollset, Knut (Peer reviewed; Journal article, 2021)Telemetry tags are increasingly used in management to monitor the migration timing of Atlantic salmon smolts (Salmo salar L.). It has been postulated that (1) effects from tagging and handling may alter migration behaviour, ...