1 Copyright © The Korean Society of Fisheries and Aquatic Science http://e-fas.org Efects of Dietary Supplementation of Spirulina and Quercetin on Growth, Innate Immune Responses, Disease Resistance Against Edwardsiella tarda, and Dietary Antioxidant Capacity in the Juvenile Olive Flounder Paralichthys olivaceus Sung-Sam Kim 1,a , Samad Rahimnejad 1 , Kang-Woong Kim 2 , Bong-Joo Lee 2 , Kyeong-Jun Lee 1,3, * 1 Department of Marine Biomedical Science, Jeju National University, Jeju 690-756, Korea 2 Aquafeed Research Center, National Fisheries Research and Development Institute, Pohang 791-923, Korea 3 Marine and Environmental Research Institute, Jeju National University, Jeju 695-814, Korea a Present address: Feed/Animal Research Institute, CJ CheilJedang Corporation, Incheon 400-103, Korea Abstract A 10-week feeding trial was conducted to examine the effects of dietary spirulina and quercetin on growth, innate immunity, disease resistance and dietary antioxidant capacity in the juvenile olive lounder. Triplicate groups of ish (initial body weight, 2.9 ± 0.01 g) were fed one of isonitrogenous (48% crude protein) and isocaloric (17.4 MJ/kg DM) experimental diets containing 0% spirulina (as a control), 3.4% spirulina, or 6.8% spirulina with or without supplementation of 0.5% quercetin (designated as Con, SP3.4, SP6.8, and SP6.8 + Q, respectively) at a rate of 3% body mass twice daily. Higher dietary antioxidant capacity was found with spirulina supplementation, and the highest value (P < 0.05) was obtained with SP6.8 + Q diet. At the end of the feeding trial, no signiicant effects were observed on growth performance, body composition and disease resistance against Edwardsiella tarda. Lysozyme activity was signiicantly increased by spirulina supplementation (P < 0.05), and the highest value was observed in the group fed SP6.8 + Q diet. Also, signiicantly higher respiratory burst activity (P < 0.05) was found in SP3.4 group. According to the results of this study, dietary supplementation of 3.4% spirulina may enhance innate immunity of olive lounder. Key words: Olive lounder, Spirulina, Quercetin, Growth, Innate immunity, Edwardsiella tarda challenge Introduction Aquaculture remains one of the fastest-growing animal food-producing sectors, accounting for almost half of total food ish and substitutes for wild ish and plants (Food and Agriculture Organization of the United Nations, 2010). How- ever, disease has been a primary constraint to the aquaculture industry, imposing severe losses on farming facilities all over the world. Antibiotic drugs have the capacity to kill or inhibit the growth of micro-organisms. However, the use of antibiotics to control ish disease needs to be restricted due to the emer- gence of drug-resistant bacteria and concerns about environ- mental hazards and food safety (Hernández Serrano, 2005). The future development of aquaculture greatly depends on the development of alternative feed ingredients that can provide higher resistance against pathogens. Marine macro- and microalgae have been supplemented in diets for different cultured ish species and have been reported to have positive effects on growth performance, feed utiliza- Received 15 May 2012; Revised 20 December 2012 Accepted 26 December 2012 *Corresponding Author E-mail: kjlee@jejunu.ac.kr http://dx.doi.org/10.5657/FAS.2013.0001 Open Access This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons. org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. pISSN: 2234-1749 eISSN: 2234-1757 Original Article Fish Aquat Sci 16(1), 1-8, 2013