Effects of carotenoid level on growth and color of bighead catfish (Clarias macrocephalus)

Abstract

This study was conducted to find out the optimal dietary pigmentation in terms of the growth performance, skin color and muscle color enhancement of bighead catfish (Clarias macrocephalus). The experiment was set up with 9 dietary treatments with three replications. Each treatment contained non pigmentation, 1.25g Xanthophyll (Xan), 2.5g Xan, 3.75g Xan, 5g Xan, 0.125g Astaxanthin (Ast)+ 0.625g Xan, 0.25g Ast+ 1.25g Xan, 0.375g Ast+ 1.875g Xan, 0,5g Ast+ 2,5g Xan equivalent kg-1 diet. The diet had about 45% protein, 8% lipid. Bighead catfish (39.28±1.21g/individual) were assigned randomly in 27 composite tanks (30 individuals /tank) with continuous aeration. They were fed twice daily (8 am and 4 pm) to satiation for 8 weeks. After 8 experimental weeks, the survival rate (SR) of bighead catfish ranged from 94 to 98%. Feed conversion ratio (FCR) was lowest at treatment 5g Xan /kg of feed (1.80±0.23). In this treatment, the yellow color of treatment 3.75 and 5g Xan kg-1 diet brought out the best compared to the other treatments. These were also the treatment that consumers appreciated and preferred.