title: Orientation behaviour of the blood-sucking bug triatoma infestans to short-chain fatty acids: synergistic effect of L-lactic acid and carbon dioxide.
abstract: The role of short-chain fatty acids in the host-seeking behaviour of Triatoma infestans larvae was investigated using a locomotion compensator. Several short-chain fatty acids were tested alone over a wide range of doses, or in combination with L-lactic acid (L-LA; 100 microg). Bugs showed no attractive response to single carboxylic acids, but when L-LA was added to airstreams carrying specific intensities of either propionic (C3; 100 microg), butyric (C4; 1 microg) or valeric acid (C5; 1 microg), these mixtures elicited an attractive response, evincing a synergistic effect. No orientation response was observed when caproic acid (C6) was offered with L-LA at the doses tested. Two blends were created: (1) C3, C4 and C5 combined at the effective doses when added with L-LA [C3C4C5 (1)], and (2) C3, C4 and C5 combined at a third of those intensities [C3C4C5 (2)]. Both blends were tested alone, with L-LA (100 microg), with a sub-threshold concentration of CO(2) (300 p.p.m. above the ambient level), and combined with both compounds together. Oriented responses of bugs were only observed with the blend (2) added with L-LA and with the combination of this lure with CO(2). This last combination evoked a behavioural response similar in intensity to that induced by a live mouse.
authors.affiliation: Laboratorio de Fisiología de Insectos, Departamento de Biodiversidad y Biología Experimental, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, 4 Piso, C1428EHA, Buenos Aires, Argentina. rbarrozo@bg.fcen.uba.ar
authors.forename: Romina B
authors.initials: RB
authors.lastname: Barrozo
authors.forename: Claudio R
authors.initials: CR
authors.lastname: Lazzari
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D002245:Carbon Dioxide / Q000494:pharmacology*; D004357:Drug Synergism; D005232:Fatty Acids, Volatile / Q000494:pharmacology*; D019344:Lactic Acid / Q000494:pharmacology*; D007814:Larva; D008124:Locomotion / Q000502:physiology; D051379:Mice; D009949:Orientation / Q000187:drug effects*; D013268:Stimulation, Chemical; D014224:Triatoma / Q000502:physiology*
chemical_list: D005232:Fatty Acids, Volatile; D002245:Carbon Dioxide; D019344:Lactic Acid