Olfactory Responses of Face Flies, Musca autumnalis,1, 2 to Bovine Feces

Abstract

Behavioral tests using a Y-tube olfactometer demonstrated that male and female face flies, Musca autumnalis DeGeer, were attracted to the odor of fresh bovine feces. Daily testing of female flies showed no significant response during the 1st 4 days. Peak attraction, with 84% of the flies responding, occurred on day 7. The number of females attracted and the number with mature ova correlated positively and significantly. Males were significantly attracted on day 1; however, response did not increase with age as in the case of female flies. Bovine diet also was found to affect the attractiveness of feces. The loci of the olfactory receptors were the basal flagellar subsegments, or funiculi, of the antennae. Oviposition tests indicated that bovine fecal odor also stimulated oviposition; however, contact was necessary to elicit maximum egg deposition; 43 and 86% reductions in ovipositon resulted from treatments involving antennectomy and nylon mesh over the surface of the feces, respectively. Simultaneous antennectomy and nylon mesh over the fecal surface stopped oviposition. Antennae again were shown to be the primary receptor organs.