Browsing Bergen Open Research Archive by Author "Imsland, Albert"
Now showing items 1-20 of 47
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Acoustic Delicing of Atlantic Salmon (Salmo salar): Fish Welfare and Salmon Lice (Lepeophtheirus salmonis) Dynamics
Hjelle, Bibbi Maria Kallay; Imsland, Albert; Vigo, Pablo Balseiro; Handeland, Sigurd Olav (Journal article; Peer reviewed, 2022)Acoustic lice treatment (AcuLice) is a newly developed system, which uses a composite acoustic sound image with low-frequency sound to remove salmon lice (Lepeophtheirus salmonis) from Atlantic salmon (Salmo salar). This ... -
Caligus elongatus and other sea lice of the genus Caligus as parasites of farmed salmonids: A review
Hemmingsen, Willy; MacKenzie, Ken; Sagerup, Kjetil; Remen, Mette; Bloch-Hansen, Karin; Imsland, Albert (Journal article; Peer reviewed, 2020)This review was prompted by reports of unusually large numbers of sea lice tentatively identified as Caligus elongatus infesting farmed salmon in northern Norway. Following a brief introduction to the sea lice problem in ... -
Catch me if you can: How to recapture lumpfish using light as an attractant
Foss, Atle; Imsland, Albert; Roth, Bjørn; Nytrø, Ane Vigdisdatter (Journal article; Peer reviewed, 2020)The use of lumpfish in salmon farming allows the removal of sea lice all year round, without the use of chemicals or mechanical treatments. In Norway alone, around 31 million lumpfish are currently put into sea pens whereas ... -
Causes of Mortality and Loss of Lumpfish Cyclopterus lumpus
Reynolds, Patrick; Imsland, Albert; Boissonnot, Lauris Jeannine Ernestine (Journal article; Peer reviewed, 2022)Data from research and commercial use of lumpfish were collected from the research facilities of Gifas (Inndyr, Northern Norway, 67.0° N, 14.0° E). The data were sourced from 12 main lumpfish groups subdivided into 66 ... -
Changes in water temperature and oxygen: the effect of triploidy on performance and metabolism in large farmed Atlantic salmon
Sambraus, Florian; Remen, Mette; Olsen, Rolf Erik; Hansen, Tom Johnny; Waagbø, Rune; Torgersen, Thomas; Lock, Erik-Jan; Imsland, Albert; Fraser, Thomas W.K.; Fjelldal, Per Gunnar (Peer reviewed; Journal article, 2018)In salmon farming, the use of sterile triploids (3N) can mitigate the problem of escapees interbreeding with wild salmon. However, triploid salmon appear less tolerant to high water temperatures and low oxygen levels ... -
Cleaner Fish Do Not Impact the Pigmentation of Salmon Lice (Lepeophtheirus salmonis) in Commercial Aquaculture Cages
Imsland, Albert; Berg, Jon Petter; Nola, Velimir; Geitung, Lena; Oldham, Tina Marie Wier (Journal article; Peer reviewed, 2023-09-10)Salmon lice are one of the biggest challenges to sustainable salmonid aquaculture. The species display high evolutionary potential, which is evident by its development of resistance to numerous chemical compounds used for ... -
Comparing Body Density of Lumpfish (Cyclopterus lumpus) to Different Operational Welfare Indicators
Imsland, Albert; Berg, Magnus Sunason; Haugland, Gyri Teien; Eliasen, Kirstin (Journal article; Peer reviewed, 2022)Farmed lumpfish (Cyclopterus lumpus) are commonly used as cleaner fish in the salmonid aquaculture industry, but a knowledge gap exists with regards to their body density. Filling this knowledge gap is of importance, as ... -
Comparison of diet composition, feeding, growth and health of lumpfish (Cyclopterus lumpus L.) fed either feed blocks or pelleted commercial feed
Imsland, Albert; Reynolds, Patrick; Jonassen, Thor Magne; Hangstad, Thor Arne; Adron, John; Elvegård, Tor Anders; Urskog, Tonje Cecilie; Hanssen, Anna; Mikalsen, Bjørn (Peer reviewed; Journal article, 2019)Two duplicate groups of individually tagged lumpfish (mean initial weight: 21.5 ± 3.2 g) were fed either a commercially available lumpfish feed or feed blocks for a period of 123 days. The aim was to evaluate and compare ... -
Comparison of diet composition, feeding, growth and health of lumpfish (Cyclopterus lumpus L.) fed either feed blocks or pelleted commercial feed
Imsland, Albert; Reynolds, Patrick; Jonassen, Thor Magne; Hangstad, Thor Arne; Adron, John; Elvegård, Tor Anders; Urskog, Tonje Cecilie; Hanssen, Anna; Mikalsen, Bjørn (Peer reviewed; Journal article, 2019)Two duplicate groups of individually tagged lumpfish (mean initial weight: 21.5 ± 3.2 g) were fed either a commercially available lumpfish feed or feed blocks for a period of 123 days. The aim was to evaluate and compare ... -
Constant High Temperature Promotes Early Changes in Testis Development Associated with Sexual Maturation in Male Atlantic Salmon (Salmo salar L.) Post-Smolts
Pino Martinez, Enrique; Braanaas, Markus; Balseiro Vigo, Pablo; Kraugerud, Marianne; Pinto Pedrosa, Cindy; Imsland, Albert; Handeland, Sigurd Olav (Journal article; Peer reviewed, 2022)Sexual maturation of post-smolts is a concern for Atlantic salmon producers, and its occurrence is dependent upon factors such as water temperature and energy availability, among others. The present study was designed to ... -
Consumption of sea lice by lumpfish (Cyclopterus lumpus): qPCR quantification and use of a non-destructive sampling method
Imsland, Albert; Micallef, Giulia; Korsnes, Kjetil; Reynolds, Patrick (Peer reviewed; Journal article, 2019)In the present study, it was attempted to quantify sea lice grazing in lumpfish by using a recently published qPCR assay. This method utilizes a small aliquot (10 μL) of the stomach fluid of the lumpfish which can be ... -
Does sedation with AQUI-S® mitigate transport stress and post transport mortality in ballan wrasse (Labrus bergyltae)?
Calabrese, Sara; Jonassen, Thor Magne; Steigum, Endre; Åsnes, Helga Øen; Imsland, Albert; Saude, Carolina Serra; Wergeland, Truls; Höglund, Erik (Journal article; Peer reviewed, 2024)Ballan wrasse (Labrus bergylta) are commonly used as cleaner fish in salmon farms as a biological treatment to mitigate sea lice infestation. Improved welfare for cleaner fish both during production of these fish and when ... -
The effect of CO2, total ammonia nitrogen and pH on growth of juvenile lumpfish (Cyclopterus lumpus)
Thorarensen, Helgi; Imsland, Albert; Monroe, Amber Christina (Journal article; Peer reviewed, 2023)The objective of this study was to examine the effects of CO2, total ammonia nitrogen (TAN: nitrogen bound as either NH3 or NH4+) and pH on the growth and survival of juvenile lumpfish in a two-month growth study. The ... -
The effect of continuous light at low temperatures on growth in Atlantic salmon reared in commercial size sea pens
Imsland, Albert; Roth, Bjørn; Fjelldal, Per Gunnar; Stefansson, Sigurd Olav; Handeland, Sigurd Olav; Mikalsen, Bjørn (Peer reviewed; Journal article, 2017-10)The aim of this study was to investigate the effect of continuous light of different duration, applied from late autumn to spring in the second year of the production cycle, on the production performance of Atlantic salmon ... -
Effect of Photoperiod and Transfer Time on Atlantic Salmon Smolt Quality and Growth in Freshwater and Seawater Aquaculture Systems
Pino Martinez, Enrique; Imsland, Albert; Hosfeld, Anne-Camilla Diesen; Handeland, Sigurd Olav (Journal article; Peer reviewed, 2023)Smoltification is a key process in Atlantic salmon aquaculture, given it prepares the fish for a successful transit from fresh to seawater. However, industry players have not yet reached a consensus on the best protocols ... -
Effect of rearing temperature on flesh quality in Arctic charr (Salvelinus alpinus)
Imsland, Albert; Ólafsdóttir, Aðalheiður; Árnason, Jón; Gústavsson, Arnþór; Thorarensen, Helgi; Gunnarsson, Snorri (Journal article; Peer reviewed, 2021)Currently, no information is available on the effect of progressively decreasing temperatures on the sensory quality of Arctic charr. The objective of this study was to investigate if and how different and progressively ... -
The effect of temperature on growth performance and aerobic metabolic scope in Arctic charr, Salvelinus alpinus (L.)
Beuvard, Christian; Imsland, Albert; Thorarensen, Helgi (Journal article; Peer reviewed, 2022)In recent years, Arctic char populations in Iceland have declined and the objective of this experiment was to throw further light on these changes by examining the effect of temperature (5, 9, 13, 17, and 21 °C) on the ... -
Effects of altered photoperiod regimes during winter on growth and gonadosomatic index in Arctic charr (Salvelinus alpinus) reared in freshwater
Foss, Atle; Siikavuopio, Sten Ivar; Imsland, Albert (Peer reviewed; Journal article, 2020)The short- and long-term effects of altered photoperiods during winter on growth and final gonadosomatic index (GSI) were investigated in 178 individually tagged 2-year-old smolt Arctic charr from an anadromous strain. The ... -
The effects of cryogenically preserved sperm on the fertilization, embryonic development and hatching success of lumpfish C. lumpus
Imsland, Albert; Purvis, Emily; Reinardy, Helena; Kapari, Lauri Teemu; Watts, Ellie Jane; Hangstad, Thor Arne (Journal article; Peer reviewed, 2022)Lumpfish (C. lumpus) are used as cleaner fish in the Atlantic salmon (Salmo salar) farming industry to remove parasitic sea lice. At present, wild lumpfish broodstock are used which puts strain on wild populations. By ... -
The Effects of Different Feed Ration Levels on Growth, Welfare Rating, and Early Maturation in Juvenile Atlantic Salmon (Salmo salar)
Imsland, Albert; Methusalemsson, Hjörtur (Journal article; Peer reviewed, 2024-02-10)To investigate the possible effect of different feed ration levels on the growth, welfare, and early maturation of juvenile Atlantic salmon, 450 salmon parr with a mean (±standard error) initial weight of 51.6 g (±0.8) ...