Abstract
Newly hatched larvae of the house fly, Musca domestica, were transferred to dung of cattle fed only fresh grass, and to artificial diet for a control, to determine the effects of the media on larval development and survival value of emergent adults. Compared with artificial diet, fresh cow dung broght about a longer developmental period for emergence by ca. 1 day at 30°C, and smaller-sized adults by ca. 5% in head width for both sexes. Emerged female adults from both media were more attracted to artificial diet than to fresh cow dung for oviposition site, when a choice was offered. However, mortality in immature stages, adult survival, and female fecundity were not significantly different between both larval media. These facts show apparently that fresh cow dung is not inadequate for the house fly to colonize open pastures as far as larval medium is concerned.