Transcriptomic responses of copepodid sea lice (Lepeophtheirus salmonis) exposed to cypermethrin (Betamax®)

This study investigates transcriptomic responses of Atlantic salmon lice, Lepeophtheirus salmonis exposed to cypermethrin, a commonly used antiparasitic agent used in aquaculture. Copepodid L. salmonis were exposed to cypermethrin (Betamax®) at a concentration of 1.0ppb An in vitro bioassay experiment was conducted using cypermethrin exposures on copepodid (larvae) sea lice (F1 generation) collected from BMA-2a New Brunswick, Canada in 2014. The bioassay exposed copepodids to 1.0 μg/L cypermethrin or a sea water control for 24 hours in glass beakers (VWR) at 12 ± 1oC. Each condition had a total volume of 500mL with six replicates and approximately 500 lice per beaker. After 24 hours, pools of ~500 copepodids were flash frozen for RNA extractions. Post 24-hours, lice were assessed for survival similarly to the technique used for staging and enumeratio first