Fujikawa Amanda, Barksdale Larry, Higley Leon G, Carter David O
Department of Entomology, University of Nebraska-Lincoln, 202 Entomology Hall, Lincoln, NE 68583-0816, USA.
J Forensic Sci. 2011 Sep;56(5):1315-8. doi: 10.1111/j.1556-4029.2011.01800.x. Epub 2011 May 6.
Bloodstain pattern analysis can be critical to accurate crime scene reconstruction. However, bloodstain patterns can be altered in the presence of insects and can confound crime scene reconstruction. To address this problem, we conducted a series of controlled laboratory experiments to investigate the effect of Lucilia sericata (Meigen) on impact bloodstains and pooled bloodstains in association with three combinations of common surfaces (linoleum/painted drywall, wood floor/wallpaper, and carpet/wood paneling). L. sericata fed from the pooled bloodstains and added insect stains through regurgitation and defecation of consumed blood. L. sericata formed defecatory trails of insect stains that indicated directionality. Defecatory stains fluoresced when viewed at 465 nm with an orange filter. These observations differed from Calliphora vicina insect stains because feeding on blood spatter was not observed and trails of insect stains were formed by L. sericata. The fluorescence of defecatory stains can be used as a method to detect insect stains and discriminate them from real bloodstains.
血迹形态分析对于准确的犯罪现场重建可能至关重要。然而，在有昆虫存在的情况下，血迹形态可能会被改变，从而混淆犯罪现场重建。为了解决这个问题，我们进行了一系列对照实验室实验，以研究丝光绿蝇（Meigen）对与三种常见表面组合（油毡/粉刷的干墙、木地板/壁纸以及地毯/木板）相关的撞击血迹和血泊的影响。丝光绿蝇以血泊为食，并通过对所消耗血液的反流和排便添加昆虫污渍。丝光绿蝇形成了指示方向性的昆虫污渍粪便痕迹。当使用橙色滤光片在465纳米处观察时，粪便污渍会发出荧光。这些观察结果与红头丽蝇的昆虫污渍不同，因为未观察到其以血迹为食，且丝光绿蝇形成了昆虫污渍痕迹。粪便污渍的荧光可作为一种检测昆虫污渍并将其与真实血迹区分开来的方法。
