HOUSE-FLIES AND PIG MANURE VOLATILES - WIND-TUNNEL BEHAVIORAL-STUDIESAND ELECTROPHYSIOLOGICAL EVALUATIONS

Nine compounds from the headspace of fresh pig manure were identified as electrophysiologically active on virgin female house fly (Musca dom estica L.) antennae, and mixtures of these compounds attracted female house flies in wind-tunnel behavioral assays. Identification was accom plished by using coupled gas chromatographic-electroantennographic (GC -EAG) recordings, coupled gas chromatographic-mass spectrometric (GCMS ) analysis, electroantennographic (EAG) assays of standards, and wind tunnel behavioral studies. The pig manure volatiles eliciting response s from female antennae were butanoic acid, 3-methylbutanoic acid, dime thyldisulfide, dimethyltrisulfide, dimethyltetrasulfide, phenol, benze neethanol, indole, and 3-methylindole. In EAG dose-response tests buta noic acid, 3-methylbutanoic acid, indole, and 3-methylindole elicited the highest responses on female house fly antennae, and dimethyltrisul fide, phenol, and benzeneethanol elicited more moderate responses. In wind-tunnel behavioral studies, female house flies new upwind in the p lume and landed on the source in response to pig manure volatiles. The ability of individual EAG-active compounds to attract female house fl ies was not significantly greater than that of the control. However, t wo mixtures, one comprised of seven EAG-active compounds and a second made up of only three compounds, were capable of attracting female fli es in a similar manner as found with pig manure. The behavioral signif icance of these compounds as potential attractants is discussed.