In both the first and second trial there were
significant differences (P= 0.003 and 0.001) in serum
osmolality (Table 5). In the first trial, serum osmolality
in the fish reared at 30 ppt (335.5 ± 4.0 mmol/
kg) was significantly higher than that in fish reared at
5 (318.8 ± 0.6 mmol/kg) or 15 (320.6 ± 1.5 mmol/kg)
ppt. Serum osmolality measurements in the second
trial showed the same pattern with fish reared at 30 ppt
having a significantly higher serum osmolality (363.1
± 3.0 mmol/kg) than fish reared at 5 (343.3 ± 2.8 mmol/
kg) or 15 (342.4 ± 2.4 mmol/kg) ppt.