The oxidative status and intestinal and liver histology of Barramundi Perch Lates calcarifer juveniles were investigated
in an experiment using different tank colors (black, red, blue, and white) over 6 weeks. It has been previously
shown that background color can affect physiological processes in different species. The background colors did not
cause significant differences in malondialdehyde, catalase, or glutathione S-transferase, whereas superoxide dismutase
and glutathione peroxidase activities were significantly higher in fish that were kept in black tanks. Plasma cortisol of
fish adapted to blue and white tanks was significantly lower than that of fish in black tanks. The liver total antioxidant
capacity was highest for fish that were maintained in white and blue tanks. The results of histopathological evaluation
revealed that tank colors did not have significant effects on intestinal mucosal and enterocyte dimensions. No
specific alterations were found in the liver or intestine of fish relative to the tank background color during the experimental
period. In conclusion, white and blue tanks resulted in improved oxidative status of Barramundi Perch
juveniles.