The effects of nucleotides on growth and immune responses in juvenile grouper, Epinephelus malabaricus

• Main Authors: Hang Wang, 王涵
• Other Authors: Shi-Yen Shiau
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/05850423311416972926

碩士 === 國立臺灣海洋大學 === 食品科學系 === 95 === Abstract Two subsequent growth trials were conducted to elucidate the effects of dietary nucleotides (NT), including inosine monophosphate (IMP), adenosine monophosphate (AMP), guanosine monophosphate (GMP), uridine monophosphate (UMP) and cytidine monophosphate (CMP), supplementation on growth and immune responses of juvenile grouper, Epinephelus malabaricus. Basal diet containing 0.5, 1.0, 1.5 and 2.0 g/kg diet mixture of IMP, AMP, GMP, UMP and CMP (1:1:1:1:1) (mixed NT) (Experiment 1) and 1.5 g/kg from each IMP, AMP, GMP, UMP or CMP (Experiment 2) were fed to grouper (mean initial weight: 5.90 ± 0.01 g, Experiment 1; 10.39 ± 0.12 g, Experiment 2) for 8 weeks. Basal diet without NT supplementation was used as control in both Experiments. In Experiment 2, 1.5 g mixed NT/kg was also included for comparison. Each diet was fed to triplicate groups of fish in a recirculated rearing system. In Experiment 1, fish fed the diet with 1.5 g mixed NT/kg had significantly (p<0.05) higher weight gain (WG) and feed efficiency (FE) than fish fed the NT-free control diet. The head kidney leukocyte superoxide anion (O2-) production ratio was higher in fish fed diets with 1.0 and 1.5 g mixed NT/kg than the fish fed diets with ≦0.5 g mixed NT/kg. The plasma lysozyme activity was higher in fish fed the diet with 1.5 g mixed NT/kg than other dietary groups. In Experiment 2, fish fed diet with 1.5 g AMP and 1.5 mixed NT/kg had highest WG and FE, followed by fish fed the diet with 1.5 g IMP/kg, and lowest in fish fed the NT-free control diet. The head kidney leukocyte O2- production ratio was higher in fish fed the diet with 1.5 g AMP/kg, followed by fish fed diets with 1.5 g UMP and 1.5 g mixed NT/kg, and lowest in fish fed the NT-free control diet. The plasma lysozyme activity was higher in fish fed diets with 1.5 g AMP and 1.5 g mixed NT/kg than other dietary groups. These results suggest that growth and immune responses were enhanced in juvenile grouper fed diet supplemented with 1.5 g mixed NT/kg diet. While growth promotion was in fish fed diet supplemented with 1.5 g/kg of individual AMP, GMP, UMP or CMP, AMP supplementation seem to be more beneficial on the immune responses in fish than other nucleotides.