Effect of water temperature and exposure duration on detachment rate of salmon lice (Lepeophtheirus salmonis); testing the relevant thermal spectrum used for delousing
Thermal delousing has become the most applied method for treatment against salmon lice. However, the temperature range used is strongly aversive for salmonids, and the method is associated with increased mortality. Treatment temperature × duration combinations should be tailored to maximise delousin...
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Language: | English |
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Online Access: | https://hdl.handle.net/11250/3092345 https://doi.org/10.1016/j.aquaculture.2022.738879 |
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ftimr:oai:imr.brage.unit.no:11250/3092345 2023-10-29T02:35:06+01:00 Effect of water temperature and exposure duration on detachment rate of salmon lice (Lepeophtheirus salmonis); testing the relevant thermal spectrum used for delousing Nilsson, Jonatan Barrett, Luke T. Mangor-Jensen, Anders Nola, Velimir Harboe, Torstein Folkedal, Ole 2023 application/pdf https://hdl.handle.net/11250/3092345 https://doi.org/10.1016/j.aquaculture.2022.738879 eng eng Havforskningsinstituttet: 14930 Aquaculture. 2023, 562 . urn:issn:0044-8486 https://hdl.handle.net/11250/3092345 https://doi.org/10.1016/j.aquaculture.2022.738879 cristin:2131477 7 562 Aquaculture Peer reviewed Journal article 2023 ftimr https://doi.org/10.1016/j.aquaculture.2022.738879 2023-10-04T22:47:15Z Thermal delousing has become the most applied method for treatment against salmon lice. However, the temperature range used is strongly aversive for salmonids, and the method is associated with increased mortality. Treatment temperature × duration combinations should be tailored to maximise delousing efficiency and minimize welfare impacts on the host fish. We tested the detachment rate of sessile, pre-adult and adult male and female salmon lice (Lepeophtheirus salmonis) as a function of ambient temperature (11–16 °C), exposure temperature (28–36 °C), and exposure duration (0–120 s). Dead Atlantic salmon (Salmo salar) hosts were used to avoid negative fish welfare and detachment of lice due to fish behaviour. Within the range tested, higher exposure temperatures were associated with higher detachment rates among pre-adult and adult lice, while no sessile lice detached at any temperature. Moreover, no treatment combination detached 100% of lice of any stage, and at 28 °C, detachment of adult females was negligible. Most detachments occurred within the first 30 s of exposure. We conclude that for a given delousing efficiency, lower temperatures must be compensated for by considerably longer exposure durations. This may be a higher risk for the welfare of the host fish than higher temperatures and shorter exposure durations. publishedVersion Article in Journal/Newspaper Atlantic salmon Salmo salar Institute for Marine Research: Brage IMR Aquaculture 562 738879 |
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Open Polar |
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Institute for Marine Research: Brage IMR |
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ftimr |
language |
English |
description |
Thermal delousing has become the most applied method for treatment against salmon lice. However, the temperature range used is strongly aversive for salmonids, and the method is associated with increased mortality. Treatment temperature × duration combinations should be tailored to maximise delousing efficiency and minimize welfare impacts on the host fish. We tested the detachment rate of sessile, pre-adult and adult male and female salmon lice (Lepeophtheirus salmonis) as a function of ambient temperature (11–16 °C), exposure temperature (28–36 °C), and exposure duration (0–120 s). Dead Atlantic salmon (Salmo salar) hosts were used to avoid negative fish welfare and detachment of lice due to fish behaviour. Within the range tested, higher exposure temperatures were associated with higher detachment rates among pre-adult and adult lice, while no sessile lice detached at any temperature. Moreover, no treatment combination detached 100% of lice of any stage, and at 28 °C, detachment of adult females was negligible. Most detachments occurred within the first 30 s of exposure. We conclude that for a given delousing efficiency, lower temperatures must be compensated for by considerably longer exposure durations. This may be a higher risk for the welfare of the host fish than higher temperatures and shorter exposure durations. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Nilsson, Jonatan Barrett, Luke T. Mangor-Jensen, Anders Nola, Velimir Harboe, Torstein Folkedal, Ole |
spellingShingle |
Nilsson, Jonatan Barrett, Luke T. Mangor-Jensen, Anders Nola, Velimir Harboe, Torstein Folkedal, Ole Effect of water temperature and exposure duration on detachment rate of salmon lice (Lepeophtheirus salmonis); testing the relevant thermal spectrum used for delousing |
author_facet |
Nilsson, Jonatan Barrett, Luke T. Mangor-Jensen, Anders Nola, Velimir Harboe, Torstein Folkedal, Ole |
author_sort |
Nilsson, Jonatan |
title |
Effect of water temperature and exposure duration on detachment rate of salmon lice (Lepeophtheirus salmonis); testing the relevant thermal spectrum used for delousing |
title_short |
Effect of water temperature and exposure duration on detachment rate of salmon lice (Lepeophtheirus salmonis); testing the relevant thermal spectrum used for delousing |
title_full |
Effect of water temperature and exposure duration on detachment rate of salmon lice (Lepeophtheirus salmonis); testing the relevant thermal spectrum used for delousing |
title_fullStr |
Effect of water temperature and exposure duration on detachment rate of salmon lice (Lepeophtheirus salmonis); testing the relevant thermal spectrum used for delousing |
title_full_unstemmed |
Effect of water temperature and exposure duration on detachment rate of salmon lice (Lepeophtheirus salmonis); testing the relevant thermal spectrum used for delousing |
title_sort |
effect of water temperature and exposure duration on detachment rate of salmon lice (lepeophtheirus salmonis); testing the relevant thermal spectrum used for delousing |
publishDate |
2023 |
url |
https://hdl.handle.net/11250/3092345 https://doi.org/10.1016/j.aquaculture.2022.738879 |
genre |
Atlantic salmon Salmo salar |
genre_facet |
Atlantic salmon Salmo salar |
op_source |
7 562 Aquaculture |
op_relation |
Havforskningsinstituttet: 14930 Aquaculture. 2023, 562 . urn:issn:0044-8486 https://hdl.handle.net/11250/3092345 https://doi.org/10.1016/j.aquaculture.2022.738879 cristin:2131477 |
op_doi |
https://doi.org/10.1016/j.aquaculture.2022.738879 |
container_title |
Aquaculture |
container_volume |
562 |
container_start_page |
738879 |
_version_ |
1781058070033465344 |