Gulbali Institute of Agriculture, Water and Environment, Charles Sturt University, Wagga Wagga, NSW 2678, Australia.
School of Agriculture, Environment and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia.
Molecules. 2022 Jun 28;27(13):4152. doi: 10.3390/molecules27134152.
Volatile cues can play a significant role in the location and discrimination of food resources by insects. Dung beetles have been reported to discriminate among dung types produced by different species, thereby exhibiting behavioral preferences. However, the role of volatile organic compounds (VOCs) in dung localization and preference remains largely unexplored in dung beetles. Here we performed several studies: firstly, cage olfactometer bioassays were performed to evaluate the behavioral responses of (Coleoptera: Scarabaeidae) to VOCs emanating from fresh horse, sheep, and cattle dung; secondly, concurrent volatilome analysis was performed to characterize volatilomes of these dung types. adults exhibited greater attraction to horse dung and less attraction to cattle dung, and they preferred dung from horses fed a pasture-based diet over dung from those fed lucerne hay. Volatilomes of the corresponding dung samples from each livestock species contained a diverse group of alkanes, alkenes, alkynes, alcohols, aldehydes, ketones, esters, phenols, and sulfurous compounds, but the composition and abundance of annotated VOCs varied with dung type and livestock diet. The volatilome of horse dung was the most chemically diverse. Results from a third study evaluating electroantennogram response and supplementary olfactometry provided strong evidence that indole, butyric acid, butanone, -cresol, skatole, and phenol, as well as toluene, are involved in the attraction of to dung, with a mixture of these components significantly more attractive than individual constituents.
挥发性线索在昆虫对食物资源的定位和辨别中起着重要作用。据报道，蜣螂能够区分不同物种产生的粪便类型，从而表现出行为偏好。然而，挥发性有机化合物（VOCs）在蜣螂粪便定位和偏好中的作用在很大程度上仍未得到探索。在这里，我们进行了几项研究：首先，在笼式嗅觉计生物测定中评估了（鞘翅目：金龟子科）对新鲜马、绵羊和牛粪散发的 VOC 的行为反应；其次，进行了同时的挥发物分析，以表征这些粪便类型的挥发物组。成虫对马粪表现出更大的吸引力，对牛粪的吸引力较小，它们更喜欢以牧草为食的马的粪便，而不是以三叶草干草为食的马的粪便。来自每个牲畜物种的相应粪便样本的挥发物组含有一组不同的烷烃、烯烃、炔烃、醇、醛、酮、酯、酚和含硫化合物，但注释 VOC 的组成和丰度随粪便类型和牲畜饮食而变化。马粪的挥发物组最具化学多样性。评估触角电图反应和补充嗅觉的第三项研究的结果提供了强有力的证据，表明吲哚、丁酸、丁酮、-甲酚、粪臭素和苯酚以及甲苯都参与了对粪便的吸引，这些成分的混合物比单个成分更具吸引力。
