Absolute ethanol intake predicts ethanol preference inDrosophila

Abstract

Factors that mediate ethanol preference in Drosophila melanogaster are not well understood. A major confound has been the use of diverse methods to estimate ethanol consumption. We measured fly consumptive ethanol preference on base diets varying in nutrients, taste and ethanol concentration. Both sexes showed an ethanol preference that was abolished on high nutrient concentration diets. Additionally, manipulating total food intake without altering the nutritive value of the base diet or the ethanol concentration was sufficient to evoke or eliminate ethanol preference. Absolute ethanol intake and food volume consumed were stronger predictors of ethanol preference than caloric intake or the dietary caloric content. Our findings suggest that the effect of the base diet on ethanol preference is largely mediated by total consumption associated with the delivery medium, which ultimately determines the level of ethanol intake. We speculate that a physiologically relevant threshold for ethanol intake is essential for preferential ethanol consumption.

Microbiome-by-ethanol interactions impact Drosophila melanogaster fitness, physiology, and behavior

“…We did, however, find an overall decrease in food consumption because of ethanol, with flies consuming roughly half as much food for each 2.5% increase in ethanol ( Figure S11 ) at 24 h, consistent with previous work ( Ja et al., 2007 ; Park and Ja, 2020 ). The same trend with decreased magnitude was observed at 48 ha and 72 h, consistent with the loss of ethanol due to evaporation ( Figures 1 D–1F).…”

“…Food consumption can have a major effect on nearly all aspects of fly biology and is directly related to lifespan through caloric restriction ( Skorupa et al., 2008 ). Furthermore, ethanol is known to affect food consumption ( Ja et al., 2007 ; Park et al., 2018 ; Park and Ja, 2020 ). We therefore measured food consumption in bacterially-colonized and bacteria-free flies on diets of 0%, 2.5% and 5% ethanol using 32P-labeled dCTP incorporation ( Deshpande et al., 2014 ).…”

An Ant-Mimicking Jumping Spider Achieves Higher Predation Probability with Lower Success Rate When Exposed to Ethanol

“…The higher the sugar content, the more easily ETOH will be produced. Thus, ETOH is an important stimulus in the environment, and many invertebrates, such as fruit flies and honeybees, show a strong preference for ETOH [9,[52][53][54]. Firstly, our results determined that M. gisti showed a strong preference for 20-30% ETOH, suggesting that spiders, at least M. gisti, could sense and voluntarily choose the ETOH.…”

Expansion and application of dye tracers for measuring solid food intake and food preference in Drosophila

“…Accordingly, methods exist for assessing food preference when flies are presented with solid, agar-based media labeled with different dyes (e.g., references 18 , 19 ), solid media labeled with a single radioactive tracer 20 , solid media tracked by oligonucleotide ingestion 21 , or liquid media via CAFE 3 . These methods have demonstrated utility and their advantages include sensitivity 3 , 18 – 21 as well as ease of measuring the tracers themselves 3 , 18 – 20 , but their implementation might be limited in some experimental settings due to the use of non-standard housing conditions or media 3 , 18 , 19 , inability to quantitate the volume of media consumed 18 , 19 , potential challenges with secure handling of radioactive flies 20 , difficulty in explicitly measuring consumption of different media simultaneously 18 – 20 , or use of sophisticated detection methods 21 . To the best of our knowledge, no dye-based methods have been described for assessing food preference in flies when they are provided with solid agar-based media under largely standard housing conditions.…”