Local inflammation at the attachment site of Lepeophtheirus salmonis drives copepodid rejection in Coho Salmon (Oncorhynchus kisutch)

Pacific salmonid species, including Pink, Coho and Chum, display varying susceptibility levels to L. salmonis, prompting interest in understanding the mechanisms behind lice resistance in these species. This study infected four salmonid species (Atlantic, Pink, Coho and Chum) with L. salmonis in three consecutive challenge trials using the same fish cohort. We analyzed skin samples from body flank and the attachment site using histological methods and spatial transcriptomics.