Abstract:
Zebrafish behavior is increasingly common in biomedical and environmental studies of chemical bioactivity. Multiple experimental arena sizes have been used to measure photolocomotion in zebrafish depending on age, endpoints observed, and instrumentation, among other factors. However, the extent to which methodological parameters may influence naïve behavioral performance and detection of behavioral changes is poorly understood. Here we measured photolocomotion and behavioral profiles of naïve larval zebrafish across arena sizes. We then performed concentration response studies with the model neurostimulant caffeine, again across various arena dimensions. We found total swimming distance of unexposed fish to increase logarithmically with arena size, which as related to circumference, area, and volume. Photomotor response during light/dark transitions also increased with arena size. Following caffeine exposure, total distance travelled was significantly (p < 0.001) affected by well size, caffeine treatment (p < 0.001), and the interaction of these two experimental factors (p < 0.001). In addition, behavioral response profiles showed differences between 96 well plates and larger well sizes. Biphasic response, with stimulation at lower concentrations and refraction at the highest concentration, was observed in dark conditions for the 96 well size only, though almost no effects were identified in the light. However, swimming behavior was significantly (p < 0.1) altered in the highest studied caffeine treatment level in larger well sizes during both light and dark periods. Our results indicate zebrafish swim more in larger arenas and arena size influences behavioral response profiles to caffeine, though differences were mostly observed between very small and large arenas. Further, careful consideration should be given when choosing arena size, because small wells may lead to restriction, while larger wells may differentially reflect biologically relevant effects. These findings can improve comparability among experimental designs and demonstrates the importance of understanding confounding methodological variables.
摘要:
斑马鱼的行为在生物医学和环境化学生物活性研究中越来越普遍。根据年龄,多种实验领域的大小已用于测量斑马鱼的光致发光,观察到的端点,和仪表,在其他因素中。然而,对方法学参数可能影响幼稚行为表现和行为变化检测的程度知之甚少。在这里,我们测量了跨竞技场大小的幼稚幼体斑马鱼的光运动和行为特征。然后我们用模型神经兴奋剂咖啡因进行浓度反应研究,再次跨越各种竞技场维度。我们发现未暴露鱼类的总游泳距离随着竞技场大小呈对数增加,与周长有关,area,和音量。光/暗过渡期间的光运动响应也随着竞技场大小而增加。咖啡因暴露后,总行进距离显著(p<0.001)受井眼大小影响,咖啡因治疗(p<0.001),以及这两个实验因素的相互作用(p<0.001)。此外,行为反应曲线显示96孔板和较大孔径之间的差异。双相反应,在较低浓度下进行刺激,在最高浓度下进行折射,仅在96孔大小的黑暗条件下观察到,尽管在光线下几乎没有发现任何影响。然而,在研究的最高咖啡因处理水平下,在光照和黑暗时期的较大井中,游泳行为发生了显着变化(p<0.1)。我们的结果表明斑马鱼在较大的竞技场游泳更多,竞技场大小会影响对咖啡因的行为反应概况,尽管差异主要是在非常小的和大的竞技场之间观察到的。Further,选择竞技场尺寸时应仔细考虑,因为小井可能会导致限制,而较大的孔可能会有差异地反映生物学相关的影响。这些发现可以提高实验设计之间的可比性,并证明了理解混杂方法变量的重要性。