2.1. Challenge
Ethical approval for the conduct of this experiment was granted
by the University of Tasmania's Animal Ethics Committee (Permit
reference A0012237). Fish rearing and infection were conducted
according to [14], with changes in the concentration of trophozoites, which was higher in the present study that in the above
mentioned. Atlantic salmon (Salmo salar) (n ¼ 100) from a single
cohort of smolt from Saltas hatchery (Wayatinah, Tasmania) (mean
initial weight ¼ 565 g, naïve to AGD) were transferred to two
4000 L independent experimental recirculating systems (50 in each
tank). Each system had independent mechanical filtration, biofiltration, foam fractionation and UV disinfection