Chen Yongkang, Pan Zhongchao, Li Xiaoyue, Yao Xinzhou, He Guilun, Xie Shiwei
Laboratory of Aquatic Animal Nutrition and Feed, College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong 524088, China.
State key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory for Aquatic Economic Animals and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, Guangdong Province, China.
Aquac Nutr. 2023 Apr 17;2023:7825559. doi: 10.1155/2023/7825559. eCollection 2023.
This study is aimed at evaluating the effectiveness of phytosterols as an alternative to cholesterol in practical diets of Pacific white shrimp from the perspective of growth and nonspecific immunity. Five diets were formulated to contain different sterol sources and levels. Two diets were supplemented with 1 g/kg cholesterol (LC (low cholesterol)) or phytosterol (LP (low phytosterol)). Other three experimental diets were supplemented with 2 g/kg cholesterol (HC (high cholesterol)), 2 g/kg phytosterol (HP (high phytosterol)), or mixed sterol source (CP, 1 g/kg cholesterol + 1 g/kg phytosterol), respectively. A total of 750 healthy and uniform-sized shrimp (0.52 ± 0.008 g) were randomly distributed into 5 groups with 3 replicates and fed with the five experimental diets for 60 days. Results showed that the growth performance of shrimp was influenced by the sterol levels and supplementation with 2 g/kg sterol level facilitated the growth of shrimp. The inclusion of phytosterol has a cholesterol-lowering effect on shrimp, as evidenced by a reduction in hemolymph cholesterol and triglyceride contents in the HP group. Besides, supplementation with 2 g/kg phytosterol or mixed sterol sources had positive effects on the hemolymph superoxide dismutase, phenol oxidase, and lysozyme as well as hepatopancreas alkaline phosphatase activities, demonstrating that the nonspecific immunity and antioxidative capacity were improved. In conclusion, phytosterols could be an appropriate alternative to partially replace dietary cholesterol in shrimp feeds. This study preliminarily revealed the effects of different sterol sources and levels on the growth and nonspecific immunity of shrimp and provided a basis for further exploration of the mechanism of phytosterol.
本研究旨在从生长和非特异性免疫的角度评估植物甾醇作为太平洋白对虾实际日粮中胆固醇替代品的有效性。配制了五种日粮，使其含有不同的甾醇来源和水平。两种日粮分别添加1 g/kg胆固醇（LC（低胆固醇））或植物甾醇（LP（低植物甾醇））。其他三种实验日粮分别添加2 g/kg胆固醇（HC（高胆固醇））、2 g/kg植物甾醇（HP（高植物甾醇））或混合甾醇来源（CP，1 g/kg胆固醇 + 1 g/kg植物甾醇）。总共750只健康且大小均匀的对虾（0.52 ± 0.008 g）被随机分为5组，每组3个重复，并投喂这五种实验日粮60天。结果表明，对虾的生长性能受甾醇水平影响，添加2 g/kg甾醇水平促进了对虾生长。植物甾醇的添加对虾有降低胆固醇的作用，HP组血淋巴胆固醇和甘油三酯含量降低证明了这一点。此外，添加2 g/kg植物甾醇或混合甾醇来源对血淋巴超氧化物歧化酶、酚氧化酶和溶菌酶以及肝胰腺碱性磷酸酶活性有积极影响，表明非特异性免疫和抗氧化能力得到改善。总之，植物甾醇可以作为一种合适的替代品，部分替代对虾饲料中的膳食胆固醇。本研究初步揭示了不同甾醇来源和水平对虾生长和非特异性免疫的影响，并为进一步探索植物甾醇的作用机制提供了依据。
