Influence des facteurs biotiques et abiotiques sur le développement larvaire des insectes Diptères nécrophages d’intérêt médical

Abstract

In forensic medicine, the growth models by weight and the duration of the development cycle are the basis of the PMI estimate, which is the interval between the time of death and the discovery of the corpse, it is important to know on which corpse tissue larvae of necrophagous flies feed. This study was conducted to evaluate the effect of the nature of the nutrient substrate on larval development of necrophagous fly larvae Calliphora vicina (Robineau-Desvoid, 1830) and Lucilia sericata (Meigen, 1826) (Diptera ; Calliphoridae) used in forensic entomology. Eggs harvested from an animal corpse (puppy), are deposited on six nutrient substrates (fish, poultry liver, camel meat, goat meat, horse and bovine meat) for their breeding under constant temperatures of 20, 25, 30 et 35°C. The weight and length of different larval stages are compared by the scheffe post-hoc test. The results obtained indicate that the larvae of Lucilia sericata fed on different substrates develop until the emergence of adults at all temperatures studied. On the other hand, Calliphora vicina does not develop optimally on temperatures of 30 and 35 ° C. The development is very rapid at 35° C compared to the temperature remains for both species. The larvae fed on fish and poultry liver, are affected in comparison with the larvae fed on the meat, they slowly reach the maximum weight. Sometimes, they produce pupae that are significantly smaller and lighter than other types of substrates. Longevity differs a little between larval stages under the four temperatures and between the six nutrient substrates.