Comparative susceptibilities of salmonids to Lepeophtheirus salmonis infections: Biochemical and physiological studies

The objective of the present study was to investigate possible mechanisms behind the differential susceptibility of coho salmon ( Oncorhynchus kisutch), rainbow trout (O. mykiss) and Atlantic salmon (Salmo salar) to sea lice (Lepeophtheirus salmonis) infection. Baseline levels of a number of innate immune factors in fish mucus and plasma were examined to establish a foundation from which to examine immunological, biochemical and physiological changes associated with lice infection. Finally, the response of lice to mucus of different species was examined.

For the sea lice challenge experiment, rainbow trout, coho and Atlantic salmon were cohabited to ensure equal sea lice infection levels. To determine the response of lice to the mucus of different species, live lice were incubated in the presence of fish skin mucus or seawater. (Abstract shortened by UMI.).