Defense Date
2024
Document Type
Directed Research Project
First Advisor
Baneshwar Singh, Ph.D.
Second Advisor
Tal Simmons, Ph.D.
Third Advisor
Jenise L Swall, Ph.D.
Abstract
Although temperature has been identified as the most important catalyst affecting blow fly larval development, other variables encountered by these species, such as the fat and moisture content of the food source, may have an impact on accurate estimations of the PMImin in forensic investigations. Thus, body composition differences between human carrion, such as variations in body fat and water percentages between younger and older individuals, or heavier persons, could affect blow fly developmental rates, and in turn cause over or under estimations of the PMImin. In this study, the weight, length, and development times of Lucilia sericata third instar larvae were measured when reared on either ground veal, ground beef, or beef liver at a constant temperature of 25 °C. The effect of varying fat and water contents of these substrates was also observed on the pupae weight and the pupae hatch mortality rate. Weight and length of third instar larvae reared on veal and beef showed similar trends over time, with both groups showing a greater maximum third instar weight and length compared to the liver group (p < 0.01). Both the veal and beef groups reached maximum weight and length at only twelve hours post initial third instar development and entered the post-feeding stage soon after, while the liver group reached maximum weight and length at 24 hours post initial third instar development and remained in the meat source past 36 hours. The average pupae weights were highest for the veal group followed by beef and then liver (p < 0.05). Pupae survivorship and mortality, and development stage durations (hr) showed no significant differences between meat types (p > 0.05). The varying fat percentages and water contents of the three food substrates had a clear effect on the development of Lucilia sericata larvae in the third instar stage, as well as in the resulting weight of pupae, verifying the potential importance of taking these variables into account during PMImin investigations.
Rights
© The Author(s)
Is Part Of
VCU Master of Science in Forensic Science Directed Research Projects
Date of Submission
4-23-2024