Sustainable aquaculture need to identify and optimize feed supplements used in the aquafeed as stimulastors of growth performance, haemolymph indices and color quality of tail fillet. In this regard, astaxanthin (AX) is the most popular synthetic pigments. High cost, low bioavailability and variable purity have limited the use of AX in the industry [1]. Curcumin as a yellow pigment obtained from rhizomes of Curcuma longa is commonly used as a spice and food colouring. In the present study, the potential of curcumin (CN) as a natural pigment in the diet of sub-adult crayfish (15.3 ± 4.9 g) was compared to that of AX based on the some biological indices including growth performance (specific growth rate, % day-1), immunological indices (lysozyme and complement) and fillet quality. Five inclusion levels (mg kg-1) of CN (50, 100, 150, 200 and 250) and AX (30, 40 and 65) together with a basal diet (control) were used in the diet for 126 days. Results showed that immunological indices including lysozyme and complement levels of the haemolymph of crayfish fed the diet containing 200 mg kg-1 increased (11.3 µg ml-1 and 12.7 unit ml-1, respectively) significantly (p≤0.05) compared to all inclusion levels of AX (mean: 7.9 µg ml-1 and 9.3 unit ml-1, respectively) and control diet (5.1 µg ml-1 and 6.7 unit ml-1, respectively). Using 200 mg kg-1 CN increased the final weight (51.8 ± 4.3 g) compared to all inclusion levels of AX (mean: 38.1 ± 5.1 g) and control group (29.5 ± 6.1 g). Specific growth rate of crayfish fed the diets containing 200 mg kg-1 CN (4.1 % day-1) increased significantly (p≤0.05) compared to all inclusion levels of AX (mean: 2.1 % day-1) and control diet (1.9 % day-1). Based on the L*a*b indices, the flesh quality of tail fillets in the crayfish fed the diets containing different levels of CN improved significantly (p≤0.05) compared to other treatments. Based on the results, using 200 mg kg-1 CN in the diet of crayfish was possible.

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