A procedure for headspace sampling and long-term storage of organic volatiles coupled with gas chromatographic-mass spectrometric (GC-MS) analysis was used to study the volatile chemosignals in a biological secretion prior to bioassay. The approach involved collecting the volatiles in evacuated canisters from an apparatus in which 1 ml of secretion was dispersed for headspace sampling. These canisters, stainless steel, 850 ml, and 100% internally electropolished, have been demonstrated to store volatile compounds, in chemically stable form, for several weeks. The GC-MS analyses provided the quantitation and identification of compounds from C3 through C14 at concentrations as low as 0.10 parts per billion volume. The approach was used to study chemosignals of musth temporal gland secretions (TGS) from a male Asian elephant (Elephas maximus). Fresh TGS material loses its biological activity within 1 hr. TGS material stored at -20°C usually looses its activity within 30 days. The usefulness of this method for long-term storage of the volatile chemosignals was demonstrated by the retention of biologically active TGS headspace compounds, as determined through bioassays, stored in these canisters for one year.

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Cyclohexanone, a naturally occurring component of male Asian elephant temporal gland secretion, was tested as a candidate elicitor of bioresponses from female Asian elephants (Elephas maximus). Four female Asian elephants were presented with synthetic cyclohexanone samples during a standardized bioassay. Four types of bioresponses, some or all of which may be important in intersexual communication, were monitored: flehmen, palatal pit area contact, scrub, and check responses. Cyclohexanone evoked persistent responses of all bioresponse types by two females, moderate response by a third female, and very few responses by a relatively unresponsive female. The results suggest that cyclohexanone may provide chemical information about to females male elephants, particularly regarding their state of musth.