The Key Laboratory of Mariculture, Ministry of Education, Fisheries college, Ocean University of China, Qingdao, 266003, China; Department of Environmental Science, Plant Biotechnology Key Laboratory of Liaoning Province, Liaoning Normal University, Dalian 116081, Liaoning, China.
The Key Laboratory of Mariculture, Ministry of Education, Fisheries college, Ocean University of China, Qingdao, 266003, China.
Fish Shellfish Immunol. 2018 Apr;75:158-163. doi: 10.1016/j.fsi.2018.01.009. Epub 2018 Jan 11.
In order to reveal the effects of l-tryptophan (Trp) on the physiology and immune response of sea cucumber (Apostichopus japonicus Selenka) exposed to crowding stress, four density groups of sea cucumbers (i.e. 4, 8, 16 and 32 individuals per 40 L water, represented as L, ML, MH and H) were fed with diets containing 0, 1, 3 and 5% l-tryptophan respectively for 75 days. The results showed that the specific growth rates (SGR) of the sea cucumber fed with diet with 3% Trp (L, 2.1; ML, 1.76; MH, 1.2; H, 0.7) were significantly higher than those fed with basal diet without Trp supplementation (P < .05). Peak amylase activity occurred at H stress density at 3% dietary Trp. Trypsin activity was higher in diet 3% in ML and MH densities than the controls, which increased by 66.4% and 53.8%. However, the lipase activity first increased and then decreased from the stocking density L to H, with highest values of 3% Trp group showed the highest value than other groups. Compared to those fed with the basal diet, sea cucumber fed diets with Trp (3%) had significantly higher phagocytic activities (0.28 OD540/10 cells, H) in coelomic fluid and respiratory burst activities (0.105 OD630/10 cells, MH) (P < .05). The results suggested that Trp cannot improve superoxide dismutase (SOD) activity at L, ML and MH densities. The alkaline phosphatase activity (AKP) significantly decreased at H stress density. Under the experimental conditions, the present results confirmed that a diet supplemented with 3% Trp was able to enhance intestinal enzyme activities, non-specific immune response and higher growth performance of A. japonicus.
为了揭示色氨酸（Trp）对遭受拥挤胁迫的海参（Apostichopus japonicus Selenka）生理和免疫反应的影响，将 4 个密度组的海参（即每 40 L 水 4、8、16 和 32 个个体，分别表示为 L、ML、MH 和 H）分别用含有 0、1、3 和 5%色氨酸的饲料喂养 75 天。结果表明，摄食含 3%Trp 饲料的海参特定生长率（SGR）（L：2.1；ML：1.76；MH：1.2；H：0.7）显著高于未补充 Trp 的基础饲料（P<0.05）。在 3%膳食 Trp 时，淀粉酶活性在 H 胁迫密度下达到峰值。在 ML 和 MH 密度下，胰蛋白酶活性高于对照组，分别增加了 66.4%和 53.8%。然而，脂肪酶活性从 L 到 H 的放养密度先增加后减少，最高值出现在 3%Trp 组，比其他组高。与摄食基础饲料相比，摄食 Trp（3%）饲料的海参在体腔液中的吞噬活性（0.28 OD540/10 个细胞，H）和呼吸爆发活性（0.105 OD630/10 个细胞，MH）显著升高（P<0.05）。结果表明，Trp 不能提高 L、ML 和 MH 密度下超氧化物歧化酶（SOD）的活性。在 H 胁迫密度下碱性磷酸酶活性（AKP）显著降低。在实验条件下，本研究结果证实，补充 3%Trp 的饲料能够增强 A. japonicus 的肠道酶活性、非特异性免疫反应和更高的生长性能。
