title: Managing aquatic parasites for reduced drug resistance: lessons from the land.
abstract: Atlantic salmon farming is one of the largest aquaculture industries in the world. A major problem in salmon farms is the sea louse ectoparasite Lepeophtheirus salmonis, which can cause stress, secondary infection and sometimes mortality in the salmon host. Sea lice have substantial impacts on farm economics and potentially nearby wild salmonid populations. The most common method of controlling sea louse infestations is application of chemicals. However, most farming regions worldwide have observed resistance to the small set of treatment chemicals that are available. Despite this, there has been little investigation of treatment strategies for managing resistance in aquaculture. In this article, we compare four archetypical treatment strategies inspired by agriculture, where the topic has a rich history of study, and add a fifth strategy common in aquaculture. We use an agent-based model (ABM) to simulate these strategies and their varying applications of chemicals over time and space. We analyse the ABM output to compare how the strategies perform in controlling louse abundance, number of treatments required and levels of resistance in the sea louse population. Our results indicated that among the approaches considered applying chemicals in combination was the most effective over the long term.
authors.affiliation: Centre for Veterinary and Epidemiological Research, Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, Prince Edward Island, Canada C1A 4P3 gmcewan@upei.ca.
authors.forename: Gregor F
authors.identifier: 0000-0001-5959-0576
authors.initials: GF
authors.lastname: McEwan
authors.affiliation: Departments of Fisheries Management and Aquatic Health Sciences, Virginia Institute of Marine Science, 1375 Greate Road, Gloucester Point, VA 23062-1346, USA.
authors.forename: Maya L
authors.initials: ML
authors.lastname: Groner
authors.affiliation: Centre for Veterinary and Epidemiological Research, Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, Prince Edward Island, Canada C1A 4P3.
authors.forename: Danielle L
authors.initials: DL
authors.lastname: Burnett
authors.affiliation: Hoplite Research Group, Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, Prince Edward Island, Canada C1A 4P3.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Fast
authors.affiliation: Centre for Veterinary and Epidemiological Research, Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, Prince Edward Island, Canada C1A 4P3.
authors.forename: Crawford W
authors.initials: CW
authors.lastname: Revie
mesh_terms: D000818:Animals; D033342:Copepoda; D005393:Fish Diseases / Q000469:parasitology* / Q000628:therapy*; D005398:Fisheries; D012474:Salmon / Q000469:parasitology*
keywords: Lepeophtheirus salmonis; Salmo salar; agent-based model; evolution of resistance; treatment strategies