背景:尽管昼夜节律对生活的各个方面都有公认的影响,对实验动物的行为测试通常忽略了与它们的自然活动模式的一致性。本研究旨在评估昼夜节律变化对结果的影响,有效性,以及大鼠不同行为测试的可靠性。
方法:三种行为测试,明暗箱试验(LDB),评估焦虑相关行为和运动活动;掩埋颗粒测试(BPT),揭示嗅觉能力和动机问题;以及蔗糖偏好测试(SPT),研究无意义的反应,用于涵盖雄性Sprague-Dawley大鼠的多个白天依赖性行为方面。
结果:我们的发现强调了不同的昼夜节律对运动活动的影响,探索性行为,嗅觉敏锐度,动机,和享乐主义反应。值得注意的是,焦虑行为不受白天条件的影响.此外,发现数据差异降低与受试者活跃期的行为测试相关。
结论:这项研究表明,对所研究的几乎所有参数都有广泛的昼夜节律影响,加上活动阶段数据变异性的显著降低。强调将实验时间与大鼠的自然活动模式对齐的重要性,我们的结果表明,在动物活动阶段进行测试不仅可以提高测试灵敏度,减少压力,并提供更具代表性的数据,但也有助于伦理动物研究(3R)和提高测试相关性。这个,反过来,提高行为研究中实验结果的可靠性和有效性,促进动物福利。
BACKGROUND: Despite the acknowledged impact of circadian rhythms on various aspects of life, behavioural tests with laboratory animals often overlook alignment with their natural activity patterns. This study aims to evaluate the influence of circadian variations on the results, validity, and reliability of different behavioural tests in rats.
METHODS: Three behavioural tests, the Light-Dark Box Test (LDB), assessing anxiety-related behaviour and locomotor activity; the Buried Pellet Test (BPT), revealing olfactory abilities and motivation issues; and the Sucrose Preference Test (SPT), studying the anhedonic response, were employed to encompass multiple daytime-dependent behavioural aspects in male Sprague-Dawley rats.
RESULTS: Our findings underscore distinct circadian effects on locomotor activity, exploratory behaviour, olfactory acuity, motivation, and hedonic response. Notably, anxious behaviour remained unaffected by daytime conditions. Furthermore, decreased data variance was found to be correlated with conducting behavioural tests during the subjects\' active phase.
CONCLUSIONS: This study demonstrates extensive circadian influences on nearly all parameters investigated, coupled with a significant reduction in data variability during the active phase. Emphasising the importance of aligning experimental timing with rats\' natural activity patterns, our results suggest that conducting tests during the active phase of the animals not only refines test sensitivity , reduces stress, and provides more representative data, but also contributes to ethical animal research (3 R) and improves test relevance. This, in turn, enhances the reliability and validity of experimental outcomes in behavioural research and promotes animal welfare.