PDF(Pubmed)
Abstract：
The optimal dietary vitamin C (VC) levels for walleye pollock (Gadus chalcogrammus) remain undefined. This study aimed to assess the effect of dietary VC levels on the growth performance and biochemical parameters of grower walleye pollock and determine the optimal VC level for their diet. Six experimental diets (VC0, VC1, VC3, VC5, VC7, and VC10) with VC levels of 3.24, 21.92, 63.31, 101.42, 145.46, and 202.51 mg kg-1 diet, respectively, were fed to fish (initial mean weight: 173.5 ± 0.31 g) for 8 weeks. At the end of the feeding trial, fish fed the VC7 and VC10 diets exhibited significantly higher growth (final body weight, weight gain, and specific growth rate) and improved feed utilization (feed efficiency and protein efficiency ratio) compared with fish fed the VC0 diet (p < 0.05). The VC3-VC10 diets significantly reduced plasma superoxide dismutase (SOD) activity (p < 0.05). Compared with the VC0 group, fish fed the VC7 and VC10 diets showed significantly elevated growth hormone and insulin-like growth factor-1 levels in plasma (p < 0.05). In conclusion, dietary VC supplementation in walleye pollock improved growth performance and SOD activity. Moreover, broken-line analysis on weight gain indicated that the optimal dietary VC level for grower walleye pollock was approximately 156.42 mg kg-1 diet.
摘要：
角膜白斑（Gaduschalogrammus）的最佳饮食维生素C（VC）水平仍不确定。本研究旨在评估日粮VC水平对种植角膜白斑的生长性能和生化参数的影响，并确定其饮食的最佳VC水平。六种实验性饮食（VC0，VC1，VC3，VC5，VC7和VC10），VC水平分别为3.24、21.92、63.31、101.42、145.46和202.51mgkg-1饮食，分别,喂食鱼（初始平均体重：173.5±0.31g）8周。在喂养试验结束时，喂食VC7和VC10饮食的鱼表现出明显更高的生长(最终体重，体重增加,和比生长速率），并与饲喂VC0日粮的鱼相比提高了饲料利用率（饲料效率和蛋白质效率比）（p<0.05）。VC3-VC10日粮显著降低血浆超氧化物歧化酶(SOD)活性(p<0.05)。与VC0组相比，饲喂VC7和VC10饮食的鱼显示血浆中生长激素和胰岛素样生长因子-1水平显着升高（p<0.05）。总之,日粮中添加VC可提高角膜白斑的生长性能和SOD活性。此外，增重的虚线分析表明，种植白斑的最佳日粮VC水平约为156.42mgkg-1。
