Enhanced transcriptomic responses in the Pacific salmon louse Lepeophtheirus salmonis oncorhynchi to the non-native Atlantic Salmon Salmo salar suggests increased parasite fitness

This study investigates host-specific gene expression of the Pacific salmon lice, Lepeophtheirus salmonis oncorhynchii, while parasitizing a resistant host (Coho salmon), two susceptible hosts (Atlantic salmon, Sockeye salmon), and a population with-held hosts (starved), over 48 hrs. Adult female sea lice were allowed to attach to three different host populations (Atlantic, Coho and Sockeye salmon), or were kept in incubation chambers devoid of hosts (starved). At 0, 24, and 48 hours, individual lice were sampled for subsequent RNA analysis.