The race between host and sea lice in the Chilean salmon farming: a genomic approach

Sea lice are a group of ectoparasite copepods negatively affecting fish health in the salmon farming industry worldwide. Due to their biology, including several stages of development with different sensitivities to chemotherapeutants and their complex host-parasite interactions, the control of sea lice represents one of the major obstacles for sustainable aquaculture. Interdisciplinary approaches are required to avoid the environmental impacts of antiparasites commercially used during the fish production cycle and the increasing emergence of drug resistance in lice populations. Herein, control methods based on genomic analyses will allow for the development of novel tools such as vaccines, immune-modulators, in-feed masking compounds and non-pharmacological therapies. This review highlights the genomic knowledge on the race between hosts and sea lice, with emphasis on Salmo salar and Oncorhynchus kisutch as host fish species and Caligus rogercresseyi as the main threat affecting the Chilean salmon industry.