AN INSECT-BASED DETECTOR OF BOVINE MANURE ODORS

We designed, constructed, and tested a single-stream insect odormeter for the measurement of bovine manure odors. The biosensing element in the odormeter is a group of six gravid face flies (Musca autumnalis De Geer) in a. 360 mt chamber A microphone, mounted above the chamber; se nses sounds made by the flies' activity. The microphone signal is proc essed by an analog root-mean-square power-measuring circuit connected to a computer data acquisition system. The apparatus allows electronic measurement of insect activity Initial experiments demonstrate the fe asibility of this system for odor detection (yes/no). Kinetic experime nts show that a dose-response curve can be produced by injecting a ser ies of increasingly odorous pulses into the system. As expected, the r epeatability of this technique is highly dependent on control of criti cal biological variables such as the flies' odor exposure history and reproductive state. If face fly responses can be positively correlated with human odor panel responses, then this technique might enable rap id reliable and inexpensive quantification of manure odors.