Sublethal effects of a new antifouling candidate on lumpfish (Cyclopterus lumpusL.) and Atlantic cod (Gadus morhuaL.) larvae

Abstract

Sublethal effects of medetomidine, a new generation antifouling compound, on lumpfish (Cyclopterus lumpus L.) and cod (Gadus morhua L.) larvae were examined. The effects on respiration rate and on colour adaptation of newly hatched larvae were assessed after 24-96 h exposure. Exposure of lumpfish larvae to the experimental concentrations resulted in a significant decrease in respiration rate (Lowest Observed Effect Concentration (LOEC) = 5-10 nM) and in the percentage of dark larvae (LOEC = 4 nM). However, no effects on respiration rate of cod larvae were detected. In addition to lumpfish larvae being affected at low concentrations of medetomidine, a reversibility of the effects was observed when 96 h-exposed larvae were incubated in clean seawater for 24-48 h. Considerations relating to the future commercialisation of medetomidine for antifouling purposes are discussed.

Use of lumpfish for sea‐lice control in salmon farming: challenges and opportunities

“…), emerging diseases (Freeman & Kristmundsson ) and antifoulants (Bellas et al . ). In Iceland, the lumpfish fishery is closely regulated and both a licence and a catch report are required, having recently been granted the world's first MSC certification for the species (Anon ), 2 years ahead of the lumpfish fishery in Greenland (Lassen et al .…”

“…World lumpfish roe production has averaged c. 3400 tonnes since 1992, but production has declined in more recent years, possibly due to overexploitation (Johannesson 2006). Other pressures that may have affected lumpfish populations include invasive species that feed on lumpfish eggs (Mikkelsen & Pedersen 2012), climate change (Perry et al 2005), emerging diseases (Freeman & Kristmundsson 2013) and antifoulants (Bellas et al 2005). In Iceland, the lumpfish fishery is closely regulated and both a licence and a catch report are required, having recently been granted the world's first MSC certification for the species (Anon 2013a), 2 years ahead of the lumpfish fishery in Greenland (Lassen et al 2015).…”

Responses in fish exposed to medetomidine, a new antifouling agent

“…In vivo increase Rainbow trout, turbot, Atlantic cod (no effect), Atlantic salmon, three-spined stickleback Lennquist et al, 2008 and unpublished data B. In vitro EROD inhibition Potent inhibitor Rainbow trout, turbot, Atlantic cod Lennquist et al (2008) C. Oxygen consumption Decreased Lumpfish, Atlantic cod (no effect), turbot Bellas et al (2005) (1) Atlantic salmon, from above: 50 nM, 5 nM and control.…”

“…Decreased oxygen consumption was observed in fry from lumpfish and turbot from concentrations from 5-10 nM and exposures up to 96 h. However, this effect was found to be reversible. In turbot, the number of gill-lid openings per minute as a measure of respiration frequency was also found to decrease following medetomidine exposure (Bellas et al, 2005;Hilvarsson et al, 2007).…”

“…It is known from earlier studies that medetomidine is very efficient in aggregating the pigment within melanophores, which gives the fish a light appearance (Karlsson et al, 1989). Additionally, fry from lumpfish and turbot showed impaired ability to adapt to a new background colour after medetomidine exposure, an effect that was reversible (Bellas et al, 2005;Hilvarsson et al, 2007). Two major studies have also been performed using melanophores from rainbow trout exposed to 0141-1136/$ -see front matter Ó 2010 Elsevier Ltd. All rights reserved.…”