Effects of sea louse chemotherapeutants on early life stages of the spot prawn ( Pandalus platyceros )

Abstract

Salmon aquaculture is among the fastest growing food-producing industries worldwide, growing from 12,000 tonnes in 1980 to over 3.2 million tonnes by (Asche et al., 2013FAO, 2020). Canada is now the fourth largest producer of farmed salmon behind Norway, Scotland and Chile producing over 100,000 tonnes of farmed salmon in 2019 (DFO, 2018a). This industry relies on permeable open net pen structures placed directly into nearshore coastal waters to hold the salmon (Asche et al., 2013). These open net pens are efficient for rearing salmon as the open transfer of seawater provides exposure to natural fluctuations in water conditions such as salinity, temperature, nutrients and dissolved oxygen.Outbreaks of parasitic sea lice (Lepeophtheirus salmonis and Caligus spp.) are a major issue in open net pen salmon farming worldwide (Costello, 2006;Krkošek et al., 2005). These ectoparasites feed on the host's skin, mucus and underlying tissue, leaving the host fish susceptible to secondary infection and disease (Costello, 2006).Outbreaks of sea lice represent the greatest source of mortality and economic losses to fish farms, causing estimated global losses of $500 million annually, accounting for 6% of product value (Costello, 2009;Mustafa et al., 2001).

Effects of aquaculture effluents on the slender sea pen Virgularia mirabilis

“…Although the toxicity of EMB has been proven in various non-target crustacean species ( e.g. alteration of mortality, moulting behaviour, gene expression, reproduction 25 – 29 ), an important knowledge gap exists concerning its impact on other taxonomic groups, as well as its potential persistence in tissues 30 – 33 .…”