Ebrahim Sotoudeh

The aim of this study was to investigate effect of tank different colors on growth and feeding performance and physiological responses of Asian sea bass (Lates calcarifer). Fish were reared in tanks with four different background colours (white, black, blue and red) for 6 weeks. Red color had a significantly positive impact on Asian sea bass growth and feeding performance compared to other colors (P<0.05). The tank background colors did not cause significant differences in body composition including protein, fat, ash and moisture (P>0.05), No significant effects of tank color were observed on hematological parameters including WBC and RBC count, hemoglobin and hematocrit value (P>0.05). Blood biochemical parameters including total protein and albumin were significantly the lowest for fish reared in white tanks compared to other colors (P<0.05); however, there was no significan difference among other tank colors. Plasma cortisol of fish reared in red background was significantly lower than that fish reared in black, blue and white backgrounds (P<0.05). While, other stress indicators including lactate and glucose were significantly lower in fish reared in blue tanks (P<0.05). This study suggested that red background is not stressful and has no negative effect on immune response in Asian sea bass. This color can be used for the culture of Asian sea bass in order to achieve the best growth and feeding performance.