Assessment of intra-specific variability in Saprolegnia parasitica populations of aquaculture facilities in British Columbia, Canada.

Among the Saprolegnia species found in aquaculture facilities, S. parasitica is recognized as the primary fish pathogen and remains an ongoing concern in fish health management. Until recently, these pathogens were kept in check by use of malachite green; due to its toxicity, this chemical has now been banned from use in many countries.