The use of alfalfa, Medicago sativa as a natural carotenoid source in diets of goldfish, Carassius auratus

• Published in: Aquaculture 2008-11, Vol.284 (1), p.196-200
• Main Authors: Yanar, Mahmut, Erçen, Zeynep, Özlüer Hunt, Arzu, Büyükçapar, Hakan Murat
• Format: Article
• Language: English
• Subjects: Alfalfa; alfalfa meal; Animal and plant ecology; Animal aquaculture; animal growth; Animal productions; Animal, plant and microbial ecology; Apo-ester; artificial diets; Biological and medical sciences; Carassius auratus; Carotenoid; carotenoids; Diet; Differences; Effects; feed composition; feed conversion; feeds; Fish; fish culture; fish feeding; Fresh water ecosystems; Freshwater; freshwater aquaculture; freshwater fish; Fundamental and applied biological sciences. Psychology; General aspects; goldfish; Medicago sativa; mortality; Pigmentation; Pigments; Skin; Studies; Synecology
• ISSN: 0044-8486; 1873-5622
• DOI: 10.1016/j.aquaculture.2008.07.050

This study was conducted to evaluate the effects of diets including 0, 5, 10, 15, 25, and 40% alfalfa meals (containing 0, 20, 40, 60, 100, and 160 mg total carotenoids/kg diet, respectively) and 60 mg apo-ester, a synthetic carotenoid/kg diet on skin pigmentation, growth, feed utilization and survival of a red variety of goldfish, Carassius auratus, with average initial weight of 10.3 g, for a rearing period of 60 days. The pigmentation degree in skin of goldfish increased significantly with increasing inclusion of alfalfa up to 25% level in the diet ( P < 0.05). However, the alfalfa inclusion over that level did not lead to more total carotenoid accumulation in the skin of fish. The diets including apo-ester and 15% alfalfa, both of which contained 60 mg carotenoid/kg diet, had similar effects on total carotenoid deposition in the skin of fish. Alfalfa addition of 25% or higher in the diet had an adverse effect on growth of fish compared to the control group ( P < 0.05). A similar phenomenon was observed in feed conversion ratio but at the 40% alfalfa inclusion level ( P < 0.05). However, no significant difference was observed in the survival of the fish. The present results demonstrate that alfalfa can be successfully used as an alternative natural carotenoid source to the synthetic apo-ester in goldfish diets. Our data indicates that 15% is a suitable dietary level of alfalfa to ensure good pigmentation, acceptable growth and feed utilization in goldfish.