The effect of marigold ( Tagetes erecta ) as natural carotenoid source for the pigmentation of goldfish ( Carassius auratus L . )

This study was conducted to evaluate the effects of diets containing 0, 100, 200 and 300 mg of carotenoid/kg diet from marigold meal on skin pigmentation, growth, feed utilization and survival of goldfish (Carassius auratus), with average initial weight of 1.8 g for a rearing period of 63 days. The pigmentation degree in skin of goldfish increased significantly with increasing inclusion of marigold meal at 200 mg of carotenoid/kg diet. However, the marigold inclusion over that level did not lead to more total carotenoid accumulation in the skin of fishes. No significant difference was observed in the survival, growth or feed utilization of the fishes. The present results demonstrate that marigold meal can be successfully used as an alternative natural carotenoid source in goldfish diets. Our data indicates that 200 mg of carotenoid/kg diet from marigold meal is a suitable dietary level to ensure good pigmentation, acceptable growth and feed utilization in goldfish.