TWENTY-FIFTH ANNUAL EASTERN FISH HEALTH WORKSHOP MARCH 10-13, 2000     Biochemical And Molecular Approaches To Understanding The Biology And Control Of The Salmon Louse (Lepeophtheirus salmonis)     Neil W. Ross1, Kara J. Firth1,2, K. Vanya Ewart1, John F. Burka2, and Stewart C. Johnson1     1Institute for Marine Biosciences, National Research Council of Canada, Halifax, Nova Scotia; 2Department of Anatomy and Physiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PEI     Since the early 1970s, infection by the salmon louse, Lepeophtheirus salmonis, has been recognized as a major disease problem in marine farmed salmonids.  Research into the biology and control of the salmon louse is ongoing at numerous institutions in Canada and abroad.  In our laboratories, we are using physiological, biochemical and molecular techniques to investigate interactions between L. salmonis and Atlantic salmon and to identify targets against which control measures such as vaccines and hemotherapeutants may be directed.  We have shown that mucus of infected salmon has elevated protease and alkaline phosphatase activity. This protease activity is from L. salmonis-derived trypsin-like enzymes, which we are currently isolating. The mucus-derived sea lice proteases will be sequenced and this sequence data will be compared to sea lice enzymes identified from an expressed sequence tag (EST) library of preadult L. salmonis constructed in our lab.  Analysis of partial cDNA sequences “ESTs” is a useful approach for gene identification.  For pathogens, this may result in the identification of targets for chemotherapy and vaccine development.   Return to 25th Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page