Purpose: This study deals with a comparative analysis of the effects of chronic exposure to a static magnetic field (SMF) and an extremely low frequency magnetic field (ELF MF) in Blaptica dubia nymphs. The outcome of such treatment on insect and fat body mass, glycogen and total lipid content in the fat body and locomotion, as an energy demanding process, were examined.

Materials and methods: One-month-old nymphs of B. dubia were exposed to an SMF (110 mT) or ELF MF (50 Hz, 10 mT) for 5 months. Their locomotion was monitored in the ‘open-field’ test for 10 min and expressed as travel distance, time in movement and average speed while in motion. After that, fat body mass and content of its main components (glycogen and total lipids) were determined. Nymph body mass was also estimated after 1 and 5 months of MF treatment.

Results: Chronic exposure to the SMF and ELF MF decreased nymph body mass and glycogen content in the fat body but increased all examined parameters of locomotion. In addition, chronic SMF treatment elevated total lipid content in the fat body, while chronic ELF MF treatment reduced fat body mass and total lipid content.

Conclusions: These findings indicate that B. dubia nymphs are sensitive to the applied MFs and possess different strategies for fuel usage in response to the SMF and ELF MF in order to satisfy increased energy demands and to overcome stressful conditions.

目的：本研究旨在比较钝齿若虫若长期暴露于静磁场（SMF）和极低频磁场（ELF MF）中的影响。检查了这种处理对昆虫和脂肪体重，糖原和脂肪体内总脂质含量以及运动的能量需求过程的结果。

材料和方法：将一个月大的B. dubia的若虫暴露于SMF（110 mT）或ELF MF（50 Hz，10 mT）下5个月。他们的运动在“野外”测试中进行了10分钟的监测，并表示为行驶距离，运动时间和运动中的平均速度。之后，测定脂肪体重及其主要成分（糖原和总脂质）的含量。在MF治疗1和5个月后，也评估了若虫的体重。

结果：长期暴露于SMF和ELF MF会降低若虫体重和脂肪体内糖原含量，但会增加所有运动参数。此外，慢性SMF治疗可增加脂肪体内的总脂质含量，而慢性ELF MF治疗可减少脂肪量和总脂质含量。

结论：这些发现表明，双歧双歧杆菌若虫对所施用的MF敏感，并对SMF和ELF MF具有不同的燃料使用策略，以满足增加的能量需求并克服压力条件。