Ivar Rønnestad's picture

Ivar Rønnestad

  • E-mailIvar.Ronnestad@uib.no
  • Phone+47 55 58 35 86+47 926 47 219
  • Visitor Address
    Thormøhlensgt. 53 A/B
  • Postal Address
    Postboks 7803
    5020 Bergen

Ivar Rønnestad has been involved in studies of physiology of fish since 1988. His main research interest is nutritional and digestive physiology of marine fish, previously mainly the larval stages, but recently also ongrowing and adults. He is currently working with peptide hormones involved in regulation of digestion, energy homeostasis and appetite, the Gut-brain axis, GI-tract physiology, transporters, nutrient sensing and amino acid metabolism.

His prior work include studies in deep-sea diving physiology at NUTEC from 1982-87. Prior affiliations include Institute of Marine Research at Austevoll (1988-89) NIFES (1993-97) and and from 1996 he has been at Department of Biology. He has conducted research stays in Japan (Kyoto University and Kagoshima Universty), Israel (IOLR), Portugal (CCMAR and University of Algarve), USA (University og California, Los Angeles, UCLA) and has an extensve research collaboration at national, european and international level

His current supervision include 2 (4 finished) postdocs, 5 PhD (+11 finished) and 3 Master student (+17 finished) at UoB and abroad.

Ivar Rønnestad is currently mainly involved in teaching in BIO104 (Comparative physiology) and BIO291 (Fish Biology II- Physiology) in addition to supervision of Master, PhD and Postdoc candidates. He is the leader of the ExcelAQUA Summer school that is a collaboration between University of Bergen, NORCE and seven Universities and Research Institutes in Japan. Students and faculty from USA and Canada also participate in the Summer school.

Through BioCEED he collaborates with Educational Researchers Sehoya Cotner and Seth Thompson at University of Minnesota.

He received the Olav Thon Foundation National award for outstanding teaching in 2019.



  • Le, Hoang Thi My Dung; Lie, Kai Kristoffer; Giroud-Argoud, Justine; Rønnestad, Ivar; Sæle, Øystein. 2019. Effects of cholecystokinin (CCK) on gut motility in the stomachless fish ballan wrasse (Labrus bergylta). Frontiers in Neuroscience. 13:553: 1-20. doi: 10.3389/fnins.2019.00553
  • Le, Hoang Thi My Dung; Lie, Kai Kristoffer; Lein, Ingrid; Kousoulaki, Katerina; Rønnestad, Ivar; Sæle, Øystein. 2019. Tarmfunksjon hos berggylte. Norsk Fiskeoppdrett. 44: 50-53.
  • Minh, Nguyen Van; Espe, Marit; Conceição, Louis E.C.; Le, Hoang Minh; Yúfera, Manuel; Engrola, Sofia A.D.; Jordal, Ann-Elise Olderbakk; Rønnestad, Ivar. 2019. The role of dietary methionine concentrations on growth, metabolism and N-retention in cobia (Rachycentron canadum) at elevated water temperatures. Aquaculture Nutrition. 25: 495-507. doi: 10.1111/anu.12875
  • Murashita, Koji; Matsunari, Hiroyuki; Fukada, Haruhisa; Suzuki, Nobuhiro; Furuita, Hirofumi; Oku, Hiromi; Rønnestad, Ivar; Yoshinaga, Hazuki; Yamamoto, Takeshi. 2019. Effect of a plant-based low-fishmeal diet on digestive physiology in yellowtail Seriola quinqueradiata. Aquaculture. 506: 168-180. doi: 10.1016/j.aquaculture.2019.03.040
  • Yufera, Manuel; Nguyen, MV; Navarro-Guillén, Carmen; Moyano, Francisco Javier; Jordal, Ann-Elise Olderbakk; Espe, Marit; Conceicao, LEC; Engrola, Sofia; Le, MH; Rønnestad, Ivar. 2019. Effect of increased rearing temperature on digestive function in cobia early juvenile. Comparative Biochemistry and Physiology A. 230: 71-80. doi: 10.1016/j.cbpa.2019.01.007
  • Hamre, Kristin; Yufera, Manuel; Rønnestad, Ivar; Boglione, Clara; Conceicao, Luis ec; Izquierdo, Marisol S. 2018. Fish Larval Nutrition and Feed Formulation: Knowledge Gaps and Bottlenecks for Advances in Larval Rearing. Chapter 4, pages 123-176. In:
    • Conceicao, Luis ec; Tandler, Amos. 2018. Success Factors for Fish Larval Production. John Wiley & Sons. 512 pages. ISBN: 978-1-119-07213-3.
  • Le, Hoang Thi My Dung; Rønnestad, Ivar; Lie, Kai Kristoffer; Giroud-Argoud, J.; Sæle, Øystein. 2018. The function of Cholecystokinin (CCK) on gut motility in the stomachless fish Ballan wrasse. Neurogastroenterology and Motility. 30.
  • Lie, Kai Kristoffer; Tørresen, Ole K.; Solbakken, Monica Hongrø; Rønnestad, Ivar; Tooming-Klunderud, Ave; Nederbragt, Alexander Johan; Jentoft, Sissel; Sæle, Øystein. 2018. 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. BMC Genomics. 19: 1-17. doi: 10.1186/s12864-018-4570-8
  • Murashita, Koji; Matsunari, Hiroyuki; Furuita, Hirofumi; Rønnestad, Ivar; Oku, Hiromi; Yamamoto, Takeshi. 2018. Effects of dietary soybean meal on the digestive physiology of red seabream Pagrus major. Aquaculture. 493: 219-228. doi: 10.1016/j.aquaculture.2018.05.005
  • Murashita, Koji; Rønnestad, Ivar; Furuita, Hirofumi; Matsunari, Hiroyuki; Oku, Hiromi; Yamamoto, Takeshi. 2018. Effects of dietary soybean meal on the bile physiology in rainbow trout, Oncorhynchus mykiss. Aquaculture. 490: 303-310. doi: 10.1016/j.aquaculture.2018.02.047

More information in national current research information system (CRIStin)

Ivar Rønnestad holds a MSc in Human Physiology (1984) and a PhD in Environmental Physiology (1993) from UoB.

NORAD- QZA-0485 SRV-13/0010: Incorporating Climate Change into Ecosystem Approaches to Fisheries & Aquacult. Managm in Sri Lanka and Vietnam (partner w/ Nha Trang Univ, Univ o Ruhuna and Univ of Tromsø)  2014-17

NFR: Intestinal function and health in Ballan wrasse – No Guts, no Glory (partner with NIFES and NOFIMA; Grant No 244170)  2015-18

Spanish Ministry of Economic Affairs and Competitiveness- National Research Programme. Utilization of gastrointestinal models as a tool for increasing the digestion efficiency of feed protein in cultured marine fish. – EFISFDIGEST (partner w/ Inst. Ciencias Marinas de Andalucía, Cadiz, Spain)  2015-18

RFF, Regional Forskningsfond: Improved feed for salmon through the selection of protein ingredients based on their functional properties (partner with EWOS innovation; Grant No 247978)  2015-18

H2020-MARIE Skłodowska-CURIE ACTIONS. Research and Innovation Staff Exchange. RISE. WiseFeed. Improving sustainability and performance of aquafeeds.  (Coordinator and PI; Grant No 691150)

NFR: Digestion and maternal/paternal transfer of microplastic contaminants in  Atlantic cod (Gadus morhua) food web (partner with NOFIMA and PI)  2016-18

Fundação para a Ciência e Tecnologia Portugal. Towards fishmeal-independent fish diets: the role of taurine (TOWTAU, PTDC/MAR/117047/2010) (partner w/CCMAR). 2012-2014

Spanish Ministry of Science and Innovation Assessment of daily rhythm in the feeding activity and the digestive function in reared larvae of marine fish. Improving the feeding protocols. (partner w/ Inst. Ciencias Marinas de Andalucía, Cadiz, Spain) 2011-13

NFR. Integrated amino acid requirement in Atlantic salmon (contracted partner w EWOS Innovation;Grant # 208352) 2011-13

NFR. CODE- a national knowledge platform for the early stages of Atlantic cod (Leader and PI). (#199482) 2010-14

NFR: Local effects of global warming: Effects of period of higher temperature than the normal range for Atlantic salmon. (contracted partner w NIFES; young outstanding scientist Grant to E.M Hevrøy# 199683) 2010-13

NFR: BIOplus. Innovative use of bioactive marine ingredients as strategy to sustain growth in fish farming prod. and to improve fish flesh quality. (contracted partner w NOFIMA; Grant # 190043). 2009-12

NFR: GutFeeling. New feeding strategies for Atlantic halibut and cod larvae to increase the output of high quality juveniles in production systems. (w partners IMR #190019) 2009-11

EU- FP7-KBBE-2007-2A. LIFECYCLE. Building a biological knowledge-base on fish lifecycles for competitive, sustainable European aquaculture. (Collaborative project, Large scale Integrating Project, Partner) 2009- 13

Helse Vest & UoB: NettMettBAP. Bioactive peptides. 2009

Fundação para a Ciência e Tecnologia Portugal. Improved dietary nitrogenformulations for marine fish larvae: effects on growth performance and skeletal formation - HYDRAA (PTDC/MAR/71685/2006)(partner w/CCMAR) 2008-11

NFR: DGS- Distended gut syndrome in larval Atlantic cod (Gadus morhua). (w industry partner SagaFjord SeaFarm #187281) 2008-09

NORAD- SRV 2701 Improving training and Research Capacity at the Nha Trang University, Vietnam- Phase II (UiT, UiB, NTNU, NUT) 2008- 12

Helse Vest & UoB: NettMettBAC. Bioactive compounds- absorption and function 2008

BTO: Hydroxyproline as an essential component in fish and animal nutrition. (contracted partner w Fiskeriforskning) 2008

NFR- Development of endocrine and digestive systems in marine fish larvae (#187063; Leiv Erikssson) 2008

NFR: Ontogeny of lipid digestion and effects of feeding pre-digested lipids to cod larvae (#179016, partner w/ proj leader NIFES; FF and IMR) 2007-09

Helse Vest & UoB: NettMett2. Network for metabolic collaborative studies in Bergen 2007

AVIT-NFR: Gene expression analysis platform (GExAP-RNA) #183740 2007

NFR: Leptin in fish - exploring the actions of a novel hormone and its role in control of appetite, growth and puberty in Atlantic salmon and cod (#172548/S40) 2006-08

NFR: Genes linked to normal development and survival of fish larvae. Strategic programme (headed by Dept. Molecular biology, UoB) 2006-08

NFR: CodGut-Digestive function in Atlantic cod larvae- effects of intensive and extensive rearing systems and correlation with peaks in mortality. (w industry partner SagaFjord SeaFarm #174229/S15) 2006-07

BILAT: PepTalk- Project establishment support for studies on peptide nutrition growth and dev. of larval fish between Norway and USA (#175021) 2006

Scandinavia - Japan Sasakawa foundation, Travel Support 2006

FUGE: Puberty in Atlantic cod (industry partner Marine Harvest) 2006

NFR: Differential protein expression in relation to dietary AA composition: a proteomic approach towards understanding growth in fish (#165203/S40) 2005-08

UoB, Marine Science Programme, Research Locus support 2005-08

Fundação para a Ciência e Tecnologia Portugal. Dietary amino acids and skeletal development in white bream - SAARGO (POCI/MAR/61623/2004) (partner w CCMAR) 2005-08

Helse Vest & UoB: NETTMETT. Network for metabolic collaborative studies in Bergen 2005-06

NFR: Intensive production of halibut fry - Larviculture and nutrition. (partner; w/ NIFES and Inst. of Mar Research; # 152932/120.) 2003-05

MariPro- NFR (partner): Use of protein and hydrolysate in Microdiets 2003

NFR: Functional development of the gut in marine fish larvae (#141990/120) 2001-03

NFR: Nutrition in larvae and juveniles of the Atlantic halibut Strategic programme (partner and steering committee member. w/ IoN, IMR) 2001-03

Meltzer Foundation UoB; Functional development of marine fish larvae 2001

UoB, Marine Science Programme, Research Locus support 2000-2004

NFR, Ontogeny of digestive function in fish larvae (#138382/140) 2000