Blar i Bergen Open Research Archive på forfatter "Nilsen, Frank"
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Genomic Resources for Sea Lice: Analysis of ESTs and Mitochondrial Genomes
Yasuike, Motoshige; Leong, Jong; Jantzen, Stuart G.; Schalburg, Kristian R. von; Nilsen, Frank; Jones, Simon R. M.; Koop, Ben F. (Peer reviewed; Journal article, 2011-07-12)Sea lice are common parasites of both farmed and wild salmon. Salmon farming constitutes an important economic market in North America, South America, and Northern Europe. Infections with sea lice can result in significant ... -
Growth reaction norms of domesticated, wild and hybrid Atlantic salmon families in response to differing social and physical environments
Solberg, Monica Favnebøe; Zhang, Zhiwei; Nilsen, Frank; Glover, Kevin (Peer reviewed; Journal article, 2013-10-28)Background: Directional selection for growth has resulted in the 9-10th generation of domesticated Atlantic salmon Salmo salar L. outgrowing wild salmon by a ratio of approximately 3:1 when reared under standard hatchery ... -
Hatching time and alevin growth prior to the onset of exogenous feeding in farmed, wild and hybrid Norwegian Atlantic salmon
Solberg, Monica Favnebøe; Fjelldal, Per Gunnar; Nilsen, Frank; Glover, Kevin (Peer reviewed; Journal article, 2014-12-01)The onset of exogenous feeding, when juveniles emerge from the gravel, is a critical event for salmonids where early emergence and large size provide a competitive advantage in the wild. Studying 131 farmed, hybrid and ... -
Heavy and light chain homologs of ferritin are essential for blood-feeding and egg production of the ectoparasitic copepod Lepeophtheirus salmonis
Heggland, Erna Irene; Trösse, Christiane; Eichner, Christiane; Nilsen, Frank (Peer reviewed; Journal article, 2019)The salmon louse, Lepeophtheirus salmonis, is a hematophagous ectoparasite of salmonid fish. Due to its blood-feeding activity, the louse is exposed to great amounts of iron, which is an essential, yet potentially toxic ... -
Host gill attachment causes blood-feeding by the salmon louse (Lepeophtheirus salmonis) chalimus larvae and alters parasite development and transcriptome
Heggland, Erna Irene; Dondrup, Michael; Nilsen, Frank; Eichner, Christiane (Journal article; Peer reviewed, 2020-05-06)Background: Blood-feeding is a common strategy among parasitizing arthropods, including the ectoparasitic salmon louse (Lepeophtheirus salmonis), feeding off its salmon host’s skin and blood. Blood is rich in nutrients, ... -
Human-induced evolution caught in action: SNP-array reveals rapid amphi-atlantic spread of pesticide resistance in the salmon ecotoparasite Lepeophtheirus salmonis
Besnier, Francois; Kent, Matthew; Skern-Mauritzen, Rasmus; Lien, Sigbjørn; Malde, Ketil; Edvardsen, Rolf; Taylor, Simon; Ljungfeldt, Lina; Nilsen, Frank; Glover, Kevin (Peer reviewed; Journal article, 2014-10-26)Background: The salmon louse, Lepeophtheirus salmonis, is an ectoparasite of salmonids that causes huge economic losses in salmon farming, and has also been causatively linked with declines of wild salmonid populations. ... -
Identification and characterisation of novel SNP markers in Atlantic cod: Evidence for directional selection
Moen, Thomas; Hayes, Ben; Nilsen, Frank; Delghandi, Madjid; Fjalestad, Kjersti T.; Fevolden, Svein-Erik; Berg, Paul R.; Lien, Sigbjørn (Peer reviewed; Journal article, 2008-02-26)Background The Atlantic cod (Gadus morhua) is a groundfish of great economic value in fisheries and an emerging species in aquaculture. Genetic markers are needed to identify wild stocks in order to ensure sustainable ... -
Identification and characterisation of the ecdysone biosynthetic genes neverland, disembodied and shade in the salmon louse Lepeophtheirus salmonis (Copepoda, Caligidae)
Sandlund, Liv; Kongshaug, Heidi; Horsberg, Tor Einar; Male, Rune; Nilsen, Frank; Dalvin, Sussie (Peer reviewed; Journal article, 2018-02-05)The salmon louse is a marine ectoparasitic copepod on salmonid fishes. Its lifecycle consists of eight developmental stages, each separated by a molt. In crustaceans and insects, molting and reproduction is controlled by ... -
Identification and Description of the Key Molecular Components of the Egg Strings of the Salmon Louse (Lepeophtheirus salmonis)
Borchel, Andreas; Kongshaug, Heidi; Nilsen, Frank (Peer reviewed; Journal article, 2019-12-03)The salmon louse Lepeophtheirus salmonis is a parasite of Atlantic salmon and other salmonids. Every year, it causes high costs for the Norwegian aquaculture industry. While the morphology of the female genital tract has ... -
Identification and molecular characterization of two acetylcholinesterases from the salmon louse, Lepeophtheirus salmonis
Kaur, Kiranpreet; Bakke, Marit Jørgensen; Nilsen, Frank; Horsberg, Tor Einar (Peer reviewed; Journal article, 2015-05-04)Acetylcholinesterase (AChE) is an important enzyme in cholinergic synapses. Most arthropods have two genes (ace1 and ace2), but only one encodes the predominant synaptic AChE, the main target for organophosphates. Resistance ... -
Identification of critical enzymes in the salmon louse chitin synthesis pathway as revealed by RNA interference-mediated abrogation of infectivity
Braden, Laura; Michaud, Dylan; Igboeli, Okechukwu O.; Dondrup, Michael; Hamre, Lars Are; Dalvin, Sussie; Purcell, Sara; Kongshaug, Heidi; Eichner, Christiane; Nilsen, Frank; Fast, Mark D. (Journal article; Peer reviewed, 2020)Treatment of infestation by the ectoparasite Lepeophtheirus salmonis relies on a small number of chemotherapeutant treatments that currently meet with limited success. Drugs targeting chitin synthesis have been largely ... -
Identification of in vivo induced antigens of the malacosporean parasite Tetracapsuloides bryosalmonae (Cnidaria) using in vivo induced antigen technology
Kumar, Gokhlesh; Sudhagar, Arun; Shivam, Saloni; Nilsen, Frank; Bartholomew, Jerri L.; El-Matbouli, Mansour (Journal article; Peer reviewed, 2022)Tetracapsuloides bryosalmonae is a malacosporean endoparasite that causes proliferative kidney disease (PKD) in wild and farmed salmonids in Europe and North America. The life cycle of T. bryosalmonae completes between ... -
Instar growth and molt increments in Lepeophtheirus salmonis (Copepoda: Caligidae) chalimus larvae
Eichner, Christiane; Hamre, Lars Are; Nilsen, Frank (Peer reviewed; Journal article, 2015-02)The salmon louse (Lepeophtheirus salmonis) is an ectoparasitic copepod causing severe problems to the fish farming industry and to wild salmonids. Morphologically, all stages in the life cycle of L. salmonis have been ... -
Intensive Farming: Evolutionary Implications for Parasites and Pathogens
Mennerat, Adèle; Nilsen, Frank; Ebert, Dieter; Skorping, Arne (Peer reviewed; Journal article, 2010)An increasing number of scientists have recently raised concerns about the threat posed by human intervention on the evolution of parasites and disease agents. New parasites (including pathogens) keep emerging and parasites ... -
Lineage-level divergence of copepod glycerol transporters and the emergence of isoform-specific trafficking regulation
Catalán-García, Marc; Chauvigné, Francois; Stavang, Jon Anders; Nilsen, Frank; Cerdà, Joan; Finn, Roderick Nigel (Journal article; Peer reviewed, 2021)Transmembrane conductance of small uncharged solutes such as glycerol typically occurs through aquaglyceroporins (Glps), which are commonly encoded by multiple genes in metazoan organisms. To date, however, little is known ... -
Losing the ‘arms race’: multiresistant salmon lice are dispersed throughout the North Atlantic Ocean
Fjørtoft, Helene Børretzen; Nilsen, Frank; Besnier, Francois; Stene, Anne; Tveten, Ann-Kristin; Bjørn, Pål Arne; Aspehaug, Vidar Teis; Glover, Kevin Alan (Journal article; Peer reviewed, 2021)Nothing lasts forever, including the effect of chemicals aimed to control pests in food production. As old pesticides have been compromised by emerging resistance, new ones have been introduced and turned the odds back in ... -
Loss of sea ice during winter north of Svalbard
Onarheim, Ingrid Husøy; Smedsrud, Lars Henrik; Ingvaldsen, Randi; Nilsen, Frank (Peer reviewed; Journal article, 2014-06-05)Sea ice loss in the Arctic Ocean has up to now been strongest during summer. In contrast, the sea ice concentration north of Svalbard has experienced a larger decline during winter since 1979. The trend in winter ice area ... -
The mechanism (Phe362Tyr mutation) behind resistance in Lepeophtheirus salmonis pre-dates organophosphate use in salmon farming
Kaur, Kiranpreet; Besnier, Francois; Glover, Kevin; Nilsen, Frank; Aspehaug, Vidar Teis; Fjørtoft, Helene Børretzen; Horsberg, Tor Einar (Peer reviewed; Journal article, 2017-09-27)The salmon louse is an ectoparasitic copepod of salmonids in the marine environment, and represents a global challenge to salmon aquaculture. A major issue is the reliance of the industry on a limited number of chemicals ... -
Microsomal triglyceride transfer protein in the ectoparasitic crustacean salmon louse (Lepeophtheirus salmonis)
Khan, Muhammad Tanveer; Dalvin, Sussie; Nilsen, Frank; Male, Rune (Peer reviewed; Journal article, 2017-08)The salmon louse, Lepeophtheirus salmonis, is an endemic ectoparasite on salmonid fish that is challenging for the salmon farming industry and wild fish. Salmon lice produce high numbers of offspring, necessitating ... -
Molecular characterisation of the salmon louse, Lepeophtheirus salmonis salmonis (Krøyer, 1837), ecdysone receptor with emphasis on functional studies of female reproduction
Sandlund, Liv; Nilsen, Frank; Male, Rune; Grotmol, Sindre; Kongshaug, Heidi; Dalvin, Sussie Trine (Peer reviewed; Journal article, 2015-02)The salmon louse Lepeophtheirus salmonis (Copepoda, Caligidae) is an important parasite in the salmon farming industry in the Northern Hemisphere causing annual losses of hundreds of millions of dollars (US) worldwide. To ...