RESUMO
Aims: To describe the influence of the seasonal variations on the development of blow fly Ch. albiceps (Wiedemann) stages as regards to the fluctuated temperature, Study Design: Eggs and larvae of the Ch. albiceps were collected from rabbit carcasses, the development period for immature and adult stages under naturally circulating room conditions were observed. Place and Duration of Study: Observations were carried out for a year (June, 2012 – May, 2013) at Zoology Dept., Zagazig University, Zagazig, Egypt. Methodology: Groups of newly formed pupae were kept in rearing jars for adult emergence. The development time (in days) from emergence to egg laying and immature growth was determined. Results: The overall development time of the Ch. albiceps exhibited significant seasonal variations corresponding to temperature changes. High temperatures accelerate the overall development, whereas low temperatures slow it down. The average period between emerging of Ch. albiceps adults, mating, spawning, larval and pupal development at low temperatures in winter was sustained the record average of 25-51 days when reared at 11°C. This period, was decreased gradually to reach average of 19-27 days at 15°C in autumn, 16-23 days at 18°C in spring and 17- 19 days, in summer months when temperature average was 23°C. Adult emergence of the Ch. albiceps fly was positively affected by temperature, it ranged from 96.12±0.24%, in summer (23°C), to 81.79±0.77 in winter (11°C). Generally female emergence was in high rates more than males and the higher female ratio was during winter (1.62). Also changes in temperatures due seasonal variations showed significant effect on the pre-oviposition and incubation periods, female fecundity, percentage of egg hatching and time of larval development. Conclusion: Changes in temperature according to seasonal variation considered an important factor for the development time for the forensically important Ch. albiceps.