Browsing Bergen Open Research Archive by Author "Oppedal, Frode"
Now showing items 1-11 of 11
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Cleaner fish growth, welfare and survival in Atlantic salmon sea cages during an autumn-winter production
Geitung, Lena; Wright, Daniel William; Oppedal, Frode; Stien, Lars Helge; Vågseth, Tone; Madaro, Angelico (Journal article; Peer reviewed, 2020)Cleaner fish used as a biological control agent against salmon lice is rapidly increasing in Atlantic salmon aquaculture. However, concerns have been raised about the welfare and mortality of cleaner fish in salmon cage ... -
Development of the salmon louse Lepeophtheirus salmonis parasitic stages in temperatures ranging from 3 to 24°C
Hamre, Lars Are; Bui, Samantha; Oppedal, Frode; Skern-Mauritzen, Rasmus; Dalvin, Sussie (Peer reviewed; Journal article, 2019-09-05)The development rate of the salmon louse Lepeophtheirus salmonis is greatly influenced by seawater temperature. This study describes how the growth rate of L. salmonis changes with temperature and identifies the extreme ... -
Fast water currents reduce production performance of post-smolt Atlantic salmon Salmo salar
Solstorm, Frida; Solstorm, David; Oppedal, Frode; Fernø, Anders; Fraser, Thomas; Olsen, Rolf Erik (Peer reviewed; Journal article, 2015-09-17)In the future, an increasing number of salmon farms may be located in areas with fast water current velocity due to limited availability of more sheltered locations. However, there is little information as to how fast ... -
The gill parasite Paramoeba perurans compromises aerobic scope, swimming capacity and ion balance in Atlantic salmon
Hvas, Malthe; Karlsbakk, Egil; Mæhle, Stig; Wright, Daniel William; Oppedal, Frode (Peer reviewed; Journal article, 2017-01)The parasitic amoeba Paramoeba perurans is an aetiological agent of amoebic gill disease (AGD), a serious problem in seawater salmonid aquaculture globally. Other finfish species are also infected and infection events may ... -
Hypoxia tolerance thresholds for post-smolt Atlantic salmon: Dependency of temperature and hypoxia acclimation
Remen, Mette; Oppedal, Frode; Imsland, Albert K.; Olsen, Rolf Erik; Torgersen, Thomas (Journal article, 2013-12-05)Atlantic salmon (Salmo salar L.) experience periodic drops in dissolved oxygen (O2) inside aquaculture sea cages. In order to evaluate whether fish function or welfare is compromised during such drops in O2 (termed hypoxia), ... -
The interaction between water currents and salmon swimming behaviour in sea cages
Johansson, David; Laursen, Frida Maria; Fernø, Anders; Fosseidengen, Jan Erik; Pascal, Klebert; Stien, Lars Helge; Vågseth, Tone; Oppedal, Frode (Peer reviewed; Journal article, 2014-05-15)Positioning of sea cages at sites with high water current velocities expose the fish to a largely unknown environmental challenge. In this study we observed the swimming behaviour of Atlantic salmon (Salmo salar L.) at a ... -
Metabolic rates, swimming capabilities, thermal niche and stress response of the lumpfish, cyclopterus lumpus
Hvas, Malthe; Folkedal, Ole; Imsland, Albert; Oppedal, Frode (Peer reviewed; Journal article, 2018-09-03)The lumpfish (Cyclopterus lumpus) is a semi-pelagic globiform teleost native to the North Atlantic with a ventral suction disc that allows for attachment onto surfaces. Some local populations are in decline and the species ... -
Not too slow, not too fast: water currents affect group structure, aggression and welfare in post-smolt Atlantic salmon Salmo salar
Solstorm, Frida; Solstorm, David; Oppedal, Frode; Olsen, Rolf Erik; Stien, Lars Helge; Fernö, Anders (Peer reviewed; Journal article, 2016)Increased swimming speed of Atlantic salmon is generally considered an improvement to welfare under aquaculture settings, as group structure is improved and agonistic behaviour reduced. As such, establishing fish farms in ... -
Production performance of Atlantic salmon post-smolts in cyclic hypoxia, and following compensatory growth
Remen, Mette; Aas, Turis Synnøve; Vågseth, Tone; Torgersen, Thomas; Olsen, Rolf Erik; Imsland, Albert; Oppedal, Frode (Peer reviewed; Journal article, 2014-07)This study investigated the production performance of the Atlantic salmon postsmolt (Salmo salar L.) subjected to cyclic oxygen reductions (hypoxia) of varying severity. Triplicate groups (N = 955) were kept at constant ... -
Snorkel sea-cage technology decreases salmon louse infestation by 75% in a full-cycle commercial test
Geitung, Lena; Oppedal, Frode; Stien, Lars Helge; Dempster, Timothy David; Karlsbakk, Egil; Nola, Velimir; Wright, Daniel William (Peer reviewed; Journal article, 2019-09-13)Methods to prevent parasite infestations in farmed fish are becoming widespread, yet tests of their effectiveness often lack commercial relevance and statistical power, which may lead to technology misuse. Here, we examined ... -
Surface environment modification in Atlantic salmon sea-cages: Effects on amoebic gill disease, salmon lice, growth and welfare
Wright, Daniel William; Geitung, Lena; Karlsbakk, Egil; Stien, Lars Helge; Dempster, Timothy David; Oldham, Tina; Nola, Velimir; Oppedal, Frode (Peer reviewed; Journal article, 2018)Surface environment modification is a potential parasite control strategy in Atlantic salmon sea-cage farming. For instance, a temporary low salinity surface layer in commercial-scale snorkel sea-cages has coincided with ...