Liu Fei, Shi Hong-Zhuan, Guo Qiao-Sheng, Yu Ye-Bing, Wang Ai-Ming, Lv Fu, Shen Wen-Biao
Institute of Chinese Medicinal Materials, Nanjing Agricultural University, Nanjing, 210095, PR China; Key Laboratory for Aquaculture and Ecology of Coastal Pool of Jiangsu Province, Yancheng Institute of Technology, Yancheng, 224051, PR China; Biology Post-doctoral Mobile Stations, College of Life Science, Nanjing Agricultural University, Nanjing, 210095, PR China.
Institute of Chinese Medicinal Materials, Nanjing Agricultural University, Nanjing, 210095, PR China.
Fish Shellfish Immunol. 2016 Apr;51:125-135. doi: 10.1016/j.fsi.2016.02.020. Epub 2016 Feb 17.
Yellow catfish (Pelteobagrus fulvidraco) has become a commercially important fish species in China and eastern Asia. High-density aquaculture has led to congestion and excessive stress and contributed to bacterial infection outbreaks that have caused high mortality. We investigated the effects of dietary supplementation with astaxanthin and emodin alone and in combination on the growth and stress resistance of yellow catfish. After 60 days of feeding, each group of fish (control, astaxanthin, emodin, and astaxanthin plus emodin (combination) groups) was exposed to acute crowding stress for 24 h, and a subsample of fish from the four groups was challenged with the bacterial septicemia pathogen Proteus mirabilis after the end of the crowding stress experiment. Compared with the control, the astaxanthin and emodin groups showed increases in serum total protein (TP), hepatic superoxide dismutase (SOD) activity and hepatic heat shock proteins 70 (HSP70) mRNA levels at 12 and 24 h after the initiation of crowding stress. The combination group exhibited increases in alanine aminotransferase (ALT) activity, aspartate aminotransferase (AST) activity, serum TP, hepatic SOD activity and hepatic HSP70 mRNA levels within 24 h after the initiation of crowding stress. However, decreases relative to the control were observed in the serum cortisol and glucose contents in the three treatment groups at 12 and 24 h after the initiation of crowding stress, in ALT and AST activity in the astaxanthin and emodin group at 24 h after the initiation of crowding stress, and in the serum lysozyme activity, serum alkaline phosphatase (ALP) activity, and hepatic catalase (CAT) and malondialdehyde (MDA) activity in the combination group at 24 h after the initiation of crowding stress. Additionally, the cumulative mortality after P. mirabilis infection was lower in all three treatment groups (57.00%-70.33%) than in the control (77.67%). Dietary supplementation with astaxanthin and emodin decreased the specific growth rate (SGR) and weight gain (WG) of healthy yellow catfish, although significant differences in mortality were not observed. These results indicate that dietary supplementation with 80 mg/kg astaxanthin and 150 mg/kg emodin can improve the anti-oxidative capabilities, hepatic HSP70 levels, and resistance to acute crowding stress of yellow catfish. Finally, an appropriate strategy for enhance yellow catfish stress resistance and disease resistance is proposed.
黄颡鱼（Pelteobagrus fulvidraco）已成为中国和东亚地区具有重要商业价值的鱼类品种。高密度水产养殖导致鱼群拥挤和过度应激，进而引发细菌感染疫情，造成高死亡率。我们研究了单独添加虾青素和大黄素以及两者联合添加对黄颡鱼生长和抗应激能力的影响。投喂60天后，每组鱼（对照组、虾青素组、大黄素组以及虾青素加 大黄素（联合）组）均经受24小时的急性拥挤应激，在拥挤应激实验结束后，从这四组中抽取部分鱼样本，用细菌性败血病病原体奇异变形杆菌进行攻毒。与对照组相比，在拥挤应激开始后的12小时和24小时，虾青素组和大黄素组的血清总蛋白（TP）、肝脏超氧化物歧化酶（SOD）活性以及肝脏热休克蛋白70（HSP70）mRNA水平均有所升高。联合组在拥挤应激开始后的24小时内，丙氨酸转氨酶（ALT）活性、天冬氨酸转氨酶（AST）活性、血清TP、肝脏SOD活性以及肝脏HSP70 mRNA水平均有所升高。然而，在拥挤应激开始后的12小时和24小时，三个处理组的血清皮质醇和葡萄糖含量相对于对照组均有所降低；在拥挤应激开始后的24小时，虾青素组和大黄素组的ALT和AST活性相对于对照组有所降低；在拥挤应激开始后的24小时，联合组的血清溶菌酶活性、血清碱性磷酸酶（ALP）活性以及肝脏过氧化氢酶（CAT）和丙二醛（MDA）活性相对于对照组有所降低。此外，在奇异变形杆菌感染后的累计死亡率方面，所有三个处理组（57.00%-70.33%）均低于对照组（77.67%）。尽管未观察到死亡率的显著差异，但添加虾青素和大黄素会降低健康黄颡鱼的特定生长率（SGR）和增重（WG）。这些结果表明，添加80mg/kg虾青素和150mg/kg大黄素可提高黄颡鱼的抗氧化能力、肝脏HSP70水平以及对急性拥挤应激的抵抗力。最后，提出了增强黄颡鱼抗应激和抗病能力的适宜策略。
