Language selection


Characterization of virulence factors in salmon lice using post-transcriptional silencing



Parasite and pathogen management – like the sea louse, Lepeophtheirus salmonis – is a priority for aquaculture site management. Similar to other parasites such as ticks, L. salmonis secretes molecules known as virulence factors (VFs) to aid in blood feeding, to reduce host immune responses, and to prevent wound healing in the host.

This project will use a genetic technique — post-transcriptional knockdown (RNA interference) — to block the salmon louse’s natural production of certain VFs. This will help the project team determine the physiological function of those VFs during infection, and whether they are important for the sea lice to successfully parasitize Atlantic Salmon. This project will test whether the VFs are important for initial attachment and infestation of Atlantic Salmon during the sea louse’s early developmental stages. It will also test whether these VFs are important for host-parasite interactions during the pre-adult and adult stages of L. salmonis, when the sea lice are more pathogenic, and when their fitness depends critically on suppressing the host’s wound-healing abilities, immunity, and blood coagulation.

The project aims to measure the reproduction of sea lice (egg production) and blood feeding (presence of blood in the gut), as well as host responses (skin biomarkers) during infection with sea lice that do not have these VFs (in which the genetic technique “knocks down,” or blocks, the VFs). This research will provide evidence to consider whether manipulating these VFs might be used as a new way to control sea lice.

Program Name

Aquaculture Collaborative Research and Development Program (ACRDP)



Principal investigator

Marc Trudel, Research Scientist, Fisheries and Oceans Canada, St. Andrews Biological Station, Maritimes Region

Team member(s)

Steven Leadbeater, Aquatic Biologist, St. Andrews Biological Station, Maritimes Region

Brent Wilson, Aquatic Biologist, St. Andrews Biological Station, Maritimes Region

Mark Fast, Associate Professor, Atlantic Veterinary College, University of PEI

Dylan Michaud, Atlantic Veterinary College, University of PEI

Collaborative Partner(s)

Laura Braden, Senior Research Scientist and Program Lead for Molecular Genetics and Biotechnology, AquaBounty Canada

Date modified: