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Abstract Lithium has been considered a potential acaricidal agent against the honey bee (Apis mellifera) parasite Varroa. It is known that lithium suppresses elevated activity and regulates circadian rhythms and light response when administered to humans as a primary therapeutic chemical for bipolar disorder and to other bipolar syndrome model organisms, given the crucial role of timing in the bee's foraging activity and the alternating sunlight vs dark colony environment bees are exposed, we explored the influence of lithium on locomotor activity (LMA) and circadian rhythm of honey bees. We conducted acute and chronic lithium administration experiments, altering light conditions and lithium doses to assess LMA and circadian rhythm changes. We fed bees one time 10 μl sucrose solution with 0, 50, 150, and 450 mM LiCl in the acute application experiment and 0, 1, 5, and 10 mmol/kg LiCl ad libitum in bee candy in the chronic application experiment. Both acute and chronic lithium treatments significantly decreased the induced LMA under constant light. Chronic lithium treatment disrupted circadian rhythmicity in constant darkness. The circadian period was lengthened by lithium treatment under constant light. We discuss the results in the context ofVarroacontrol and lithium's effect on bipolar disorder.
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Effects of coumaphos on locomotor activities of different honeybee (Apis mellifera L.) subspecies and ecotypes
Abstract The effects of acute sublethal doses of coumaphos, an acaricide used againstVarroa destructorinfestation in beekeeping, on the locomotor activities of four native honeybee subspecies of Türkiye including two ecotypes (Carniolan honeybee -A. m. carnica, Syrian honeybee -A. m. syriaca, Caucasian honeybee-A. m. caucasica, and Muğla and Yığılca ecotypes of Anatolian honeybeeA. m. anatoliaca) were investigated using an individual locomotor activity monitoring system. Analysis of locomotor activity data in the first 12-h, last 12-h, and 24-h time periods showed that bees fromcaucasicaandcarnicasubspecies were not affected by coumaphos at all three acute doses (1, 2, and 5 μg coumaphos in 10 μl sucrose syrup for each bee). In contrast, bees fromA. m. syriacasubspecies showed significantly elevated locomotor activity levels at 2 and 5 μg coumaphos doses within the first 12 h. Bees from both Muğla and Yığılca ecotypes ofanatoliacasubspecies also showed elevated locomotor activity levels at 5 μg coumaphos dose but the magnitude of increase was lower in these ecotypes compared to that seen insyriacasubspecies in the first 12-h period. In general, increasing doses of coumaphos resulted in increased locomotor activity (locomotor activity), with differences in sensitivity across honeybee populations. Possible mechanisms underlying this variance and suggestions for further studies are discussed.
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- PAR ID:
- 10526582
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Apidologie
- Volume:
- 54
- Issue:
- 4
- ISSN:
- 0044-8435
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s13592-023-01017-9
