3.2.5 JUVENILE RE-EXPOSURE EXPERIMENT
Out of the 12 control replicates from the larval exposure experiment, six were exposed to copper for the first time at the juvenile stage, i.e. naïve group, and the remaining six were kept in clean FSW, i.e. control group. At 25 d post-settlement,juveniles in all groups, except for controls, were exposed to a High level (10.4 μg/L)of copper for two days. Juveniles were then placed into clean FSW until 40 d postsettlement when mortality, growth and normal development were assessed.Experimental set-up and maintenance routine were the same as described for settlers.Mortality and growth were measured as described for settlers. All juveniles in each container were rated for normal development and were deemed as ‘abnormal’ when body shape was strongly irregular, or lacked spines or pigmentation (Table 3.3) when observed under a dissecting microscope (40x magnification).