The effect of temperature on ability of Lepeophtheirus salmonis to infect and persist on Atlantic salmon

• Published in: Journal of fish diseases 2020-12, Vol.43 (12), p.1519-1529
• Main Authors: Dalvin, Sussie, Are Hamre, Lars, Skern‐Mauritzen, Rasmus, Vågseth, Tone, Stien, Lars, Oppedal, Frode, Bui, Samantha
• Format: Article
• Language: English
• Subjects: Animals; aquaculture; Biological activity; Copepoda - physiology; Crustaceans; Dynamics; Ectoparasites; Ectoparasitic Infestations - parasitology; Epidemic models; Epidemiology; Fish; Fish Diseases - parasitology; Fish parasites; Freshwater fishes; infection success; Infections; Lepeophtheirus salmonis; Lice; Marine fishes; moult; Parasites; Pest control; Risk assessment; Risk management; Salmo salar; Salmo salar - parasitology; Salmon; sea lice; Success; Survival; Temperature; Temperature effects
• ISSN: 0140-7775; 1365-2761
• DOI: 10.1111/jfd.13253

The salmon louse (Lepeophtheirus salmonis) is an ecologically and economically important parasite of salmonid fish. Temperature is a strong influencer of biological processes in salmon lice, with development rate increased at higher temperatures. The successful attachment of lice onto a host is also predicted to be influenced by temperature; however, the correlation of temperature with parasite survival is unknown. This study describes the effects of temperature on infection success, and survival on the host during development to the adult stage. To accurately describe infection dynamics with varying temperatures, infection success was recorded on Atlantic salmon (Salmo salar) between 2 and 10°C. Infection success ranged from 20% to 50% and was strongly correlated with temperature, with the highest success at 10°C. Parasite loss was monitored during development at eight temperatures with high loss of lice at 3 and 24°C, whilst no loss was recorded in the temperature range from 6 to 21°C. Sea temperatures thus have large effects on the outcome of salmon louse infections and should be taken into account in the management and risk assessment of this parasite. Improving understanding of the infection dynamics of salmon lice will facilitate epidemiological modelling efforts and efficiency of pest management strategies.