title: Volatile Organic Compounds of Decaying Piglet Cadavers Perceived by Nicrophorus vespilloides.
abstract: In the necrophagous burying beetle Nicrophorus vespilloides (Coleoptera: Silphidae), cadaver preference appears to depend on cadaver size and on the maturity of the beetle. We previously showed that newly emerged females with immature ovaries prefer later stages of decomposition of large cadavers. Our present aim is the determination of specific chemical compounds involved in the discrimination of cadaveric odor bouquets and the recognition of specific stages of decomposition. We used headspace samples of maggot-infested piglet cadavers at various decomposition stages and performed gas chromatography coupled with electroantennography (GC-EAD) to record 45 EAD-active compounds. Using GC coupled with mass spectrometry, we identified 13 of the EAD-active compounds. The headspace of the fresh decomposition stage was characterized mainly by high relative amounts of trimethylpyrazine. High relative amounts of dimethyl trisulfide were characteristic of bloated, post-bloating, and advanced decay stages. The advanced decay and dry remains stages were dominated by high relative amounts of phenol. Statistically, this compound had the highest impact on discrimination between the fresh decomposition stage, which is important for mature burying beetles for reproduction, and the advanced decay stage, which is nutritionally more attractive for newly emerged beetles. Phenol might, therefore, function as a key substance for newly emerged female burying beetles, so that they can locate suitable cadavers for feeding to maturation.
authors.affiliation: Institute of Evolutionary Ecology and Conservation Genomics, Ulm University, Helmholtzstraße 10-1 Containerstadt, 89081, Ulm, Germany. christian.hoermann-von-und@uni-ulm.de.
authors.forename: Christian
authors.initials: C
authors.lastname: von Hoermann
authors.affiliation: Institute of Zoology, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Ruther
authors.affiliation: Institute of Evolutionary Ecology and Conservation Genomics, Ulm University, Helmholtzstraße 10-1 Containerstadt, 89081, Ulm, Germany.
authors.forename: Manfred
authors.initials: M
authors.lastname: Ayasse
mesh_terms: D000818:Animals; D001681:Biological Assay; D002102:Cadaver; D001517:Coleoptera / Q000187:drug effects* / Q000502:physiology*; D055724:Electrophysiological Phenomena / Q000187:drug effects; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D008297:Male; D055696:Olfactory Perception / Q000187:drug effects*; D013552:Swine; D055549:Volatile Organic Compounds / Q000032:analysis / Q000494:pharmacology*
chemical_list: D055549:Volatile Organic Compounds
keywords: 2- and 3-methylbutyric acid; Cadaver odor; Coleoptera; Decomposition stages; Dimethyl trisulfide; EAD-active compounds; Forensic entomology; GC/MS analysis; Phenol; Silphidae