Harper Claudia, Wolf Jeffrey C
Experimental Pathology Laboratories, 45600 Terminal Drive, Sterling, VA 20166.
ILAR J. 2009;50(4):387-96. doi: 10.1093/ilar.50.4.387.
Fish and other aquatic animals are subject to a broad variety of stressors because their homeostatic mechanisms are highly dependent on prevailing conditions in their immediate surroundings. Yet few studies have addressed stress as a potential confounding factor for bioassays that use fish as test subjects. Common stressors encountered by captive fish include physical and mental trauma associated with capture, transport, handling, and crowding; malnutrition; variations in water temperature, oxygen, and salinity; and peripheral effects of contaminant exposure or infectious disease. Some stress responses are detectable through gross or microscopic examination of various organs or tissues; as reported in the literature, stress responses are most consistently observed in the gills, liver, skin, and components of the urogenital tract. In addition to presenting examples of various stressors and corresponding morphologic effects, this review highlights certain challenges of evaluating stress in fish: (1) stress is an amorphous term that does not have a consistently applied definition; (2) procedures used to determine or measure stress can be inherently stressful; (3) interactions between stressors and stress responses are highly complex; and (4) morphologically, stress responses are often difficult to distinguish from tissue damage or compensatory adaptations induced specifically by the stressor. Further investigations are necessary to more precisely define the role of stress in the interpretation of fish research results.
鱼类和其他水生动物会受到各种各样的应激源影响，因为它们的稳态机制高度依赖于其周围环境的当前状况。然而，很少有研究将应激作为使用鱼类作为受试对象的生物测定中的一个潜在混杂因素来探讨。圈养鱼类常见的应激源包括与捕获、运输、处理和拥挤相关的身体和精神创伤；营养不良；水温、氧气和盐度的变化；以及污染物暴露或传染病的外周效应。一些应激反应可通过对各种器官或组织进行大体或显微镜检查来检测；正如文献所报道的，应激反应在鳃、肝脏、皮肤和泌尿生殖道的组成部分中最常被观察到。除了列举各种应激源及其相应形态学效应的例子外，本综述还强调了评估鱼类应激的某些挑战：（1）应激是一个模糊的术语，没有始终如一应用的定义；（2）用于确定或测量应激的程序本身可能就具有应激性；（3）应激源与应激反应之间的相互作用高度复杂；（4）在形态学上，应激反应往往难以与应激源特异性诱导的组织损伤或代偿性适应区分开来。需要进一步研究以更精确地界定应激在鱼类研究结果解释中的作用。
