Blar i Bergen Open Research Archive på forfatter "Rønnestad, Ivar"
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1H NMR metabolic profiling of cod (Gadus morhua) larvae: potential effects of temperature and diet composition during early developmental stages
Chauton, Matilde Skogen; Galloway, Trine Falck; Kjørsvik, Elin; Størseth, Trond Røvik; Puvanendran, Velmurugu; van der Meeren, Terje; Karlsen, Ørjan; Rønnestad, Ivar; Hamre, Kristin (Peer reviewed; Journal article, 2015)Marine aquaculture offers a great source of protein for the increasing human population, and farming of, for example, Atlantic salmon is a global industry. Atlantic cod farming however, is an example of a promising industry ... -
Cloning, tissue and ontogenetic expression of the taurine transporter in the flatfish Senegalese sole (Solea senegalensis)
Pinto, Wilson; Rønnestad, Ivar; Jordal, Ann-Elise Olderbakk; Gomes, Ana Silva; Dinis, Maria Teresa; Aragão, Cláudia (Peer reviewed; Journal article, 2012-04)Flatfish species seem to require dietary taurine for normal growth and development. Although dietary taurine supplementation has been recommended for flatfish, little is known about the mechanisms of taurine absorption in ... -
Copepods enhance nutritional status, growth and development in Atlantic cod (Gadus morhua L.) larvae – can we identify the underlying factors?
Karlsen, Ørjan; van der Meeren, Terje; Rønnestad, Ivar; Mangor-Jensen, Anders; Galloway, Trine Falck; Kjørsvik, Elin; Hamre, Kristin (Peer reviewed; Journal article, 2015-05-19)The current commercial production protocols for Atlantic cod depend on enriched rotifers and Artemia during first-feeding, but development and growth remain inferior to fish fed natural zooplankton. Two experiments were ... -
Diet affects the redox system in developing Atlantic cod(Gadus morhua) larvae
Penglase, Samuel; Edvardsen, Rolf; Furmanek, Tomasz; Rønnestad, Ivar; Karlsen, Ørjan; van der Meeren, Terje; Hamre, Kristin (Peer reviewed; Journal article, 2015-08)The growth and development of marine fish larvae fed copepods is superior to those fed rotifers, but the underlying molecular reasons for this are unclear. In the following study we compared the effects of such diets on ... -
Effect of a plant-based low-fishmeal diet on digestive physiology in yellowtail Seriola quinqueradiata
Murashita, Koji; Matsunari, Hiroyuki; Fukada, Haruhisa; Suzuki, Nobuhiro; Furuita, Hirofumi; Oku, Hiromi; Rønnestad, Ivar; Yoshinaga, Hazuki; Yamamoto, Takeshi (Peer reviewed; Journal article, 2019)To characterize the effects of a plant-based low-fishmeal (LFM) diet on the digestive physiology of yellowtail, Seriola quinqueradiata, we prepared two isonitrogenous and isolipidic diets; an FM-based diet (diet Control, ... -
Effect of increased rearing temperature on digestive function in cobia early juvenile
Yufera, Manuel; Nguyen, MV; Navarro-Guillén, Carmen; Moyano, Francisco Javier; Jordal, Ann-Elise Olderbakk; Espe, Marit; Conceicao, LEC; Engrola, Sofia; Le, MH; Rønnestad, Ivar (Peer reviewed; Journal article, 2019)The present study is focused to elucidate the main characteristics of the digestive function of this carnivorous fast-growing fish living at high temperatures. With this aim, we have examined the effects of an increased ... -
Effects of cholecystokinin (CCK) on gut motility in the stomachless fish ballan wrasse (Labrus bergylta)
Le, Hoang Thi My Dung; Lie, Kai Kristoffer; Giroud-Argoud, Justine; Rønnestad, Ivar; Sæle, Øystein (Peer reviewed; Journal article, 2019-06-07)Cholecystokinin (CCK) is well-known as a key hormone that inhibits stomach emptying and stimulates midgut motility in gastric species. However, the function of CCK related to gut motility in agastric fish, especially in ... -
Functional modifications associated with gastrointestinal tract organogenesis during metamorphosis in Atlantic halibut (Hippoglossus hippoglossus)
Gomes, Ana Silva; Kamisaka, Yuko; Harboe, Torstein; Power, Deborah M.; Rønnestad, Ivar (Peer reviewed; Journal article, 2014-02-19)Background: Flatfish metamorphosis is a hormone regulated post-embryonic developmental event that transforms a symmetric larva into an asymmetric juvenile. In altricial-gastric teleost fish, differentiation of the stomach ... -
Hypothalamic agrp and pomc mRNA Responses to Gastrointestinal Fullness and Fasting in Atlantic Salmon (Salmo salar, L.)
Kalananthan, Tharmini; Murashita, Koji; Rønnestad, Ivar; Ishigaki, Mitsumasa; Takahashi, Kota; Silva, Marta Sofia; Wakabayashi, Yuki; Lai, Floriana; Shimizu, Munetaka; Nilsen, Tom Ole; Martinez, Enrique Pino; Gomes, Ana S. (Journal article; Peer reviewed, 2020-02-11)The orexigenic agouti-related protein (AgRP) and the anorexigenic pro-opiomelanocortin (POMC) are crucial players in the control of feed intake in vertebrates, yet their role in teleosts has not been fully established. ... -
Loss of stomach, loss of appetite? Sequencing of the ballan wrasse (Labrus bergylta) genome and intestinal transcriptomic profiling illuminate the evolution of loss of stomach function in fish
Lie, Kai Kristoffer; Tørresen, Ole K.; Solbakken, Monica Hongrø; Rønnestad, Ivar; Tooming-Klunderud, Ave; Nederbragt, Alexander Johan; Jentoft, Sissel; Sæle, Øystein (Peer reviewed; Journal article, 2018-03-06)Background: The ballan wrasse (Labrus bergylta) belongs to a large teleost family containing more than 600 species showing several unique evolutionary traits such as lack of stomach and hermaphroditism. Agastric fish are ... -
Methionine deficiency does not increase polyamine turnover through depletion of hepatic S-adenosylmethionine in juvenile Atlantic salmon
Espe, Marit; Andersen, Synne Marte; Holen, Elisabeth; Rønnestad, Ivar; Veiseth-Kent, Eva; Zerrahn, Jens-Erik; Aksnes, Anders (Peer reviewed; Journal article, 2014-10)During the last few decades, plant protein ingredients such as soya proteins have replaced fishmeal in the diets of aquacultured species. This may affect the requirement and metabolism of methionine as soya contains less ... -
The ontogeny and brain distribution dynamics of the appetite regulators NPY, CART and pOX in larval Atlantic cod (Gadus morhua L.)
Le, Hoang T.M.D.; Angotzi, Anna Rita; Ebbesson, Lars O.E.; Karlsen, Ørjan; Rønnestad, Ivar (Peer reviewed; Journal article, 2016-04-21)Similar to many marine teleost species, Atlantic cod undergo remarkable physiological changes during the early life stages with concurrent and profound changes in feeding biology and ecology. In contrast to the digestive ... -
Ossification of Atlantic cod (Gadus morhua) – Developmental stages revisited
Sæle, Øystein; Haugen, Trine; Karlsen, Ørjan; van der Meeren, Terje; Bæverfjord, Grete; Hamre, Kristin; Rønnestad, Ivar; Moren, Mari; Lie, Kai Kristoffer (Peer reviewed; Journal article, 2017-02)In studies of marine larvae, it is common to use days post-hatch as a developmental reference point. We show that age is a poor measure of morphological and physiological development in Atlantic cod. Therefore, we propose ... -
The peptide transporter 1a of the zebrafish Danio rerio, an emerging model in nutrigenomics and nutrition research: Molecular characterization, functional properties, and expression analysis
Vacca, Francesca; Barca, Amilcare; Gomes, Ana S.; Mazzei, Aurora; Piccinni, Barbara; Cinquetti, Raffaella; Del Vecchio, Gianmarco; Romano, Alessandro; Rønnestad, Ivar; Bossi, Elena; Verri, Tiziano (Peer reviewed; Journal article, 2019-12-19)Background: Peptide transporter 1 (PepT1, alias Slc15a1) mediates the uptake of dietary di/tripeptides in all vertebrates. However, in teleost fish, more than one PepT1-type transporter might function, due to specific whole ... -
Reconstructed 3D models of digestive organs of developing Atlantic cod (Gadus morhua) larvae
Kamisaka, Yuko; Rønnestad, Ivar (Peer reviewed; Journal article, 2010)Six 3D models of the digestive system during ontogeny were reconstructed from histological sections of Atlantic cod larvae. The 3D models clearly visualize the following features: folding of the gut rotation; subdivision ... -
The role of dietary methionine concentrations on growth, metabolism and N-retention in cobia (Rachycentron canadum) at elevated water temperatures
Nguyen, Minh Van; Espe, Marit; Conceição, Louis E.C.; Le, Hoang Minh; Yúfera, Manuel; Engrola, Sofia A.D.; Jordal, Ann-Elise Olderbakk; Rønnestad, Ivar (Peer reviewed; Journal article, 2019-04)This study determined impacts of dietary methionine concentrations at two temperatures on growth, feeding efficiency and N‐metabolites in juvenile cobia. Methionine concentrations of the experimental diets were deficient ... -
The two-step development of a duplex retina involves distinct events of cone and rod neurogenesis and differentiation
Valen, Ragnhild; Eilertsen, Mariann; Edvardsen, Rolf; Furmanek, Tomasz; Rønnestad, Ivar; van der Meeren, Terje; Karlsen, Ørjan; Nilsen, Tom Ole; Helvik, Jon Vidar (Peer reviewed; Journal article, 2016-08)Unlike in mammals, persistent postembryonic retinal growth is a characteristic feature of fish, which includes major remodeling events that affect all cell types including photoreceptors. Consequently, visual capabilities ...