Effects of dietary chitosan oligosaccharide complex with rare earth on growth performance and innate immune response of turbot, Scophthalmus maximusL

• Published in: Aquaculture research Vol. 44; no. 5; p. 683
• Main Authors: Cui, Liqing, Xu, Wei, Ai, Qinghui, Wang, Dongfeng, Mai, Kangsen
• Format: Journal Article
• Language: English
• Published: Oxford Hindawi Limited 01.04.2013
• ISSN: 1355-557X; 1365-2109
• DOI: 10.1111/j.1365-2109.2011.03072.x

An 8-week-feeding trial was conducted to investigate the effect of dietary chitosan oligosaccharide complex with rare earth (COS-REE) on growth performance and innate immune response of turbot, Scophthalmus maximusL. (Initial average weight was (12.1 ± 0.1) g) as well as disease resistance against Edwardsiella tarda. Six practical diets (approximately 53.01% protein and 12.57% lipid) were formulated to contain graded levels (0, 75, 150, 300, 600 and 1200 mg kg-1) of COS-REE. Results of the present study showed that, compared to the control group (0 mg kg-1), the specific growth rate (SGR) was significantly higher in fish fed the diet with 300 mg kg-1 COS-REE (P < 0.05), while the feed conversion ratio (FCR) significantly decreased (P < 0.05). The phagocytic index (PI) and the activity of super oxide dismutase (SOD) of serum in fish fed the diet with 300 mg kg-1 COS-REE was significantly higher than fish fed the control diet (P < 0.05), but no significant differences were observed in malondialdehyde (MDA) and hepatic metallothionein (MT) concentrations. After 8 weeks, fish were challenged by intraperitoneal injection with E. tarda, and COS-REE-treated fish demonstrated increased protection capability. These results suggested that COS-REE could enhance growth, innate immunity and disease resistance in turbot, and the optimum dose was approximately 300 mg kg-1. [PUBLICATION ABSTRACT]