Effects of manganese sources and dietary manganese level on growth performance, antioxidative function and tissue mineral accumulation in grouper Epinephelus coioides
NIE Jia-quan, DONG Xiao-hui, TAN Bei-ping, CHI Shu-yan, YANG Qi-hui, LIU Hong-yu, ZHANG Shuang
College of Fisheries, Laboratory of Aquatic Animal Nutrition and Feed, Guangdong Ocean University, Zhanjiang 524088, China
Abstract: The effects of dietary organic manganese sources and level on growth performance, antioxidative function and tissue mineral accumulation were investigated in grouper Epinephelus coioides with initial body weight of 12.26 g. The grouper juveniles were fed eleven experimental diets supplemented with the graded levels of glycine manganese and manganese 2-Hydroxy-4-(methylthio) butyrate at a dose of 0, 2, 4, 8, 16 and 32 mg Mn/kg diet to satiation at water temperature of (28±2)℃ for 8 weeks. There was significantly lower weight gain rate (WGR) in the control group than in the Mn supplemented groups (P<0.05), in which the WGR was shown to be increased at first with the increase in manganese level, then to stable level. The requirement of juveniles for dietary manganese was estimated to be 9.04 mg/kg in glycine manganese and 12.87 mg/kg in manganese 2-Hydroxy-4-(methylthio) butyrate using the broken-line model with WGR as the dependent variables, the biological utilization of glycine manganesas being as high as 1.78 times as manganese 2-Hydroxy-4-(methylthio) butyrate in terms of WGR. The activities of Mn-SOD in the liver were found to be increased with elevated supplementation of dietary Mn, and the MDA contents in the liver decreased with the increasing dietary Mn level. The nonlinear model based on quadratic polynomial regression equations, with Mn-SOD as the dependent variables, revealed that the requirement of juveniles for dietary manganese was estimated to be 21.15 mg/kg in glycine manganese and 20.61 mg/kg in manganese 2-Hydroxy-4-(methylthio) butyrate. The manganese contents of vertebrae and whole fish were found to be increased significantly with increase in supplementation of dietary Mn (P<0.05). However, the Fe contents of vertebrae and whole fish were significant decreased with increase in supplementation of dietary Mn (P<0.05) when supplementation of dietary Mn . In conclusion, further addition of Mn did not lead to elevated growth in the grouper fed the diet containing enough Mn. But on the growth performance of grouper, the bioavailability of glycine manganese was found to be higher than the manganese 2-Hydroxy-4-(methylthio) butyrate, both showing the similar level of antioxidation ability.
聂家全, 董晓慧, 谭北平, 迟淑艳, 杨奇慧, 刘泓宇, 章双. 锰源和锰水平对斜带石斑鱼幼鱼生长、 抗氧化功能和矿物元素沉积的影响[J]. 大连海洋大学学报, 2015, 30(2): 196-202.
NIE Jia-quan, DONG Xiao-hui, TAN Bei-ping, CHI Shu-yan, YANG Qi-hui, LIU Hong-yu, ZHANG Shuang. Effects of manganese sources and dietary manganese level on growth performance, antioxidative function and tissue mineral accumulation in grouper Epinephelus coioides. Journal of Dalian Ocean University, 2015, 30(2): 196-202.
2015, Vol. 30 
