POST-EMBRYONARY DEVELOPMENT OF Cochliomyia macellaria (FABRICIUS) (DIPTERA: CALLIPHORIDAE) REARED ON NATURAL DIETS PROCESSED IN CONTROLLED CONDITIONS. The performance of Cochliomyia macellaria (Fabricius) immature forms was evaluated in experimental conditions. Larvae were reared on equine meat and of sardine diets stored in an oven at 30 °C for different periods of time. Fresh diets lots were first stored in a freezer (- 15 °C) and transferred to a refrigerator for 24 hours. Portions of the equine meat and of the sardine were then sucessively stored at 30 °C for 96, 72, 48 and two hours, and, 72, 48, 24 and two hours, respectively. One sample was caracterized by the maintence of the diet in refrigerator, among 11 days, when red meat was utilized. One-hundred g diet in 4 replications/ treatment and 2 g diet per 1 larva ratio were used. The postfeeding larvae were separated and weighed individually. The rate of postembryonic development was not homogenously affected by previous storage of the diet at 30 °C, using horse meat. An expressive percentual of postfeeding larvae obtained from the substrates processed for 48 and 96 hours weighed less than 60,0 mg. The emergence of adults stayed between 73 e 97%. The rate of postembryonic development was reduced when the sardine diet was used previously maintened at 30°C for 72 hours. The postfeeding larvae obtained from the substrates processed, in this temperature, for two, 24 e 48 hours weighed between 57,0 and 65,0 mg. The mean weight of specimens from the remaining treatment was significantly lower (50,0 mg). The rate of immature forms survival ranged from 68 - 88 %