Fisheries College, Ocean University of China, 5 Yushan Road, Qingdao, Shandong 266003, PR China.
Fisheries College, Ocean University of China, 5 Yushan Road, Qingdao, Shandong 266003, PR China.
Fish Shellfish Immunol. 2014 Feb;36(2):325-35. doi: 10.1016/j.fsi.2013.12.002. Epub 2013 Dec 17.
Stocking density and hypoxia are considered priority issues in aquaculture research. In this study, two experiments were carried out in order to investigate the effects of chronic stress (stocking density) and acute stress (hypoxia) on the immune physiology responses (hematology, serum cortisol, glucose, total protein and the mRNA expression of CYP 1A) of juvenile Amur sturgeon (Acipenser schrenckii). In the chronic stress study, three triplicate groups of Amur sturgeon (42.0 ± 2.3 g) were reared in nine square concrete ponds (4.4 × 4.4 × 0.45 m³) at three stocking densities (3.7, 6.9 and 9.0 kg/m³) for 50 days. In the acute stress study, three triplicate groups: normal group (7 mg/l), hypoxia group 1 (5 mg/l) and hypoxia group 2 (3 mg/l) were used in nine 100 L indoor tanks. Sampling was performed at the end of the stocking density experiment (50 days) and at 0, 0.5, 1.5, 3 and 6 h after hypoxia stress. The results showed that increased stocking density reduced the morphological indexes (hepatosomatic index, spleen-somatic index and kidney-somatic index), while total protein and hemoglobin increased significantly in the stressed group. In response to hypoxia, the levels of cortisol, glucose and hematological parameters elevated significantly after this stress. As for spleen-somatic index, there was a decline after hypoxia though H1 group returned to the normal level at 3 h and 6 h after hypoxia stress. Additionally, In order to better understand the immune response of Amur sturgeon to chronic and acute stressors, we cloned the complete coding sequence of Amur sturgeon CYP 1A for the first time and investigated its tissue-specific expression and stress-induced expression. CYP 1A mRNA in liver showed over expressions both in crowding condition and in hypoxia stress. The same trend was also found in spleen and kidney which may provide evidence that CYP 1A could serve as a good indicator of immune response in Amur sturgeon. In addition, the result suggested a typical immune response both in high stocking density and hypoxia stress. But the chronically stressed fish might have an adaptation capability to survive under a stable crowding condition without a change in some immune parameters (cortisol, glucose, WBCs and RBCs).
养殖密度和缺氧被认为是水产养殖研究中的优先问题。在这项研究中，进行了两项实验，以研究慢性应激（养殖密度）和急性应激（缺氧）对幼龄史氏鲟（Acipenser schrenckii）免疫生理反应（血液学、血清皮质醇、葡萄糖、总蛋白和 CYP1A 的 mRNA 表达）的影响。在慢性应激研究中，将三组重复的史氏鲟（42.0 ± 2.3 g）在九个方形混凝土池塘（4.4 × 4.4 × 0.45 m³）中以三种养殖密度（3.7、6.9 和 9.0 kg/m³）养殖 50 天。在急性应激研究中，使用三个重复组：正常组（7 mg/l）、缺氧组 1（5 mg/l）和缺氧组 2（3 mg/l）在九个 100 L 室内水箱中。在养殖密度实验结束时（50 天）和缺氧后 0、0.5、1.5、3 和 6 h 进行采样。结果表明，养殖密度增加会降低形态指标（肝体比、脾体比和肾体比），而应激组的总蛋白和血红蛋白显著增加。对缺氧的反应，皮质醇、葡萄糖和血液学参数在应激后显著升高。至于脾体比，虽然 H1 组在缺氧后 3 小时和 6 小时恢复正常水平，但在缺氧后有所下降。此外，为了更好地了解史氏鲟对慢性和急性应激源的免疫反应，我们首次克隆了史氏鲟 CYP1A 的完整编码序列，并研究了其组织特异性表达和应激诱导表达。肝中 CYP1A mRNA 在拥挤条件和缺氧应激下均表达过度。脾和肾也有同样的趋势，这可能为 CYP1A 可作为史氏鲟免疫反应的良好指标提供证据。此外，结果表明在高养殖密度和缺氧应激下存在典型的免疫反应。但是，处于慢性应激状态的鱼类可能具有在稳定拥挤条件下生存的适应能力，而不会改变某些免疫参数（皮质醇、葡萄糖、白细胞和红细胞）。
