Vácha Martin
Department of Animal Physiology and Immunology, Faculty of Science, Masaryk University, Kotlárská 2, Brno, 611 37, Czech Republic.
J Exp Biol. 2006 Oct;209(Pt 19):3882-6. doi: 10.1242/jeb.02456.
A relatively simple all-laboratory behavioural assay of insect magnetoreception has been developed. We found non-conditioned reactions of American cockroach to the periodical shifts of the geomagnetic field. The movement activity of animals individually placed into Petri dishes was scored as a number of body turns. Test groups were exposed to a 90-min interval with the horizontal component of the geomagnetic field periodically rotated by 60 degrees back and forth with 5 min periodicity. The number of body turns was compared with the preceding and following intervals and with the corresponding interval of the control group kept in the natural field. We obtained a significant increase in activity when changes in field were applied. Interestingly, the period of increased activity did not coincide precisely with the 90 min stimulation interval. The onset of animal restlessness was delayed by tens of minutes and persisted correspondingly after the stimulation stopped. A respective evaluation criterion was suggested and verified. Owing to its simplicity and minimal manipulation of the insects, together with low demands on the memory and motivation state of animals, the approach potentially may be used as a laboratory diagnostic tool indicating magnetoreception in insect neurophysiology research.
一种相对简单的用于昆虫磁感受的全实验室行为测定方法已经开发出来。我们发现美国蟑螂对地磁场周期性变化的非条件反应。将单独放置在培养皿中的动物的运动活性记录为身体转动的次数。测试组暴露于90分钟的时间段内，地磁场的水平分量以5分钟的周期周期性地前后旋转60度。将身体转动的次数与之前和之后的时间段以及置于自然磁场中的对照组的相应时间段进行比较。当施加磁场变化时，我们观察到活性显著增加。有趣的是，活性增加的时间段与90分钟的刺激时间段并不完全一致。动物不安的开始延迟了数十分钟，并且在刺激停止后相应地持续存在。提出并验证了相应的评估标准。由于其简单性以及对昆虫的操作极少，同时对动物的记忆和动机状态要求较低，该方法有可能被用作实验室诊断工具，用于昆虫神经生理学研究中的磁感受指示。
