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Ethanol dependency affects the health of more than 15 million adults in the United States of America. Honey bees have been used as a model for ethanol studies because of similarities in neural structure to vertebrates and their complex social behaviors. This study compares honey bee free-flight visitation to a food source after exposure to ethanol in aqueous sucrose. Individual bees were followed making six attachment visits to a test-station containing 1M sucrose. After attachment, honey bees were randomly assigned to one of five groups: 0%, 2.5%, 5%, 10% EtOH, or a staged increase in ethanol concentrations (2.5%, 5%, 10%). The results indicated that honey bees tolerate up to 2.5% EtOH without avoidance or altered behavior, and up to 5% EtOH without avoidance but with slower trips. At 10% ethanol, attrition was 75% by the 18th return trip. Bees in the staged increase in concentration group were more likely to return than bees that were offered 10% ethanol in sucrose solution after attachment. The results of this study imply that ethanol-induced tolerance to the effects of ethanol can be achieved in honey bees through incremental increase in EtOH but only in terms of attrition. Other measures of foraging efficiency did not show ethanol-induced tolerance. Understanding how ethanol tolerance develops in bees may provide insight into these processes in humans with minimized ethical considerations.
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Preliminary Analysis of Genetic Markers for Functional Ethanol Tolerance in Honey Bees (Apis mellifera) Using a Free-Flying Paradigm
Honey bees are a commonly used species for alcohol research due to their genome being fully sequenced, their behavioral changes following consumption, and their preference for alcohol. The purpose of this article is to provide a preliminary examination of the genetic expression of heat shock protein 70 (HSP70) and big potassium ion channel protein (BKP) in honey bees following the consumption of either 0%, 2.5%, 5%, or 10% ethanol (EtOH) solutions. The foraging behaviors of the bees were observed and recorded through their return and drinking times. There were significant differences in the return and drinking times between some of the groups. The bees in the 10% condition took significantly longer to return compared to the other groups. Additionally, the bees in the 5% group spent significantly more time drinking compared to the bees in the control (0%) group. There were no significant differences in HSP70 or BKP between the different ethanol groups. Cumulatively, these findings suggest that, while bees may exhibit behavioral differences, the differences in gene expression may not be observed at the transcriptional level.
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- Award ID(s):
- 1950805
- PAR ID:
- 10593189
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Insects
- Volume:
- 15
- Issue:
- 7
- ISSN:
- 2075-4450
- Page Range / eLocation ID:
- 494
- 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/10.3390/insects15070494
