Environmental Conditions Affecting Development of House Fly Larvae in Poultry Manure

Abstract

Musca domestica L. eggs were placed in fresh poultry manure under different temperatures (22° to 38°C) and relative humidity (19 to 80%) conditions to determine the hatchability of fly eggs, growth of larvae, production of pupae, and physical changes in the poultry manure. Moisture loss from the manure was recorded daily. The inoculation rates varied from 2 to 5 g of fly eggs per 4 kg of fresh poultry manure. Fly eggs and larvae were also placed under caged laying hens for the catabolism of the manure as it was voided. Optimum production of dry pupae was obtained with a combination of 3 g of fly eggs in 4 kg of fresh poultry manure at 27°C and relative humidity of 41%. Moisture in the manure was reduced from 78.5 to 55.0% by larval activity and aeration. When relative humidity was increased from 38 to 70%, the production of pupae at 34° to 38°C was significantly ( P <0.01) increased. The combination of 2 g of fly eggs per 4 kg of fresh poultry manure produced significantly ( P <0.01) heavier larvae than other combinations in the experiment. In comparison with fresh poultry manure, the manure residue after larval digestion had less odor, contained less moisture, and was granular in texture. The fly larvae developed well under the caged layers, reducing freshly voided manure to granular material within a few hours. A fungal development in digested manure was observed at 32°C when the relative humidity was increased to 80%.