Abstract: In this study, the responses of turbots to crowding stress were studied though obverting the changes of immune and stress index in blood, spleen, head kidney, gills and skin before and after being inoculated with attenuated Edwardsiella tarda vaccine, using turbots cultured in different initial stocking densities (low density: 5 kg/m2, medium density: 10 kg/m2, high density: 20 kg/m2). The results showed that: the immune indexes such as serum interleukin (1L-1β), complement (C3), immunoglobulin M (IgM), lysozyme (LZM) and tumor necrosis factor (TNF-α) of turbots in the low density group were significantly higher than those of the medium and high density groups (P＜0.05); the blood cortisol level of turbots in the low density group was significantly higher than that of the medium and low density groups (P＜0.05); heat shock protein (HSP70) gene expression in the high density turbots was significantly higher than that of the medium and low density groups; and, immunoglobulin M (IgM) expression in low density turbots was higher than that of the medium and high density groups. Above all, in order to improve the immune effect and reduce stress response of turbot, it is suggested to adopt low density (5 kg/m2) breeding system.

Key words: Scophthalmus maximus, Edwardsiella tarda vaccine, crowding stress, serum immune index, gene expression

摘要： 通过对3个养殖初始密度（低、中、高密度组分别为5、10、20 kg/m2）的大菱鲆（Scophthalmus maximus）接种减毒迟缓爱德华氏菌疫苗，观察其血液、脾脏、头肾、鳃和皮肤中部分免疫和应激指标的变化规律，研究经接种疫苗操作后大菱鲆应对拥挤胁迫的应激响应。结果显示，低密度养殖的白细胞介素（1L-1β）、补体（C3）、免疫球蛋白M（IgM）、溶菌酶（LZM）和肿瘤坏死因子（TNF -α）等免疫指标显著高于中、高密度组（P＜0.05），高密度组血液中皮质醇的含量高于中、低密度组（P＜0.05）；通过基因表达分析发现，高密度组的热休克蛋白（HSP70）表达量显著高于中、低密度组；低密度组的免疫球蛋白M（IGM）表达量高于中、高密度组。研究表明，为提高大菱鲆的免疫效果、减少应激反应，可以采用低密度（5 kg/m2）养殖。

关键词: 大菱鲆, 迟缓爱德华氏菌疫苗, 拥挤胁迫, 血清指标, 基因表达