Department of Entomology, Texas AM University - 2475 TAMU, College Station, TX 77843, USA; Department of Animal Evolution and Biodiversity, University of Goettingen - Untere Karspuele 2, 37073 Goettingen, Germany.
Department of Entomology, Texas AM University - 2475 TAMU, College Station, TX 77843, USA; Department of Animal Evolution and Biodiversity, University of Goettingen - Untere Karspuele 2, 37073 Goettingen, Germany.
Forensic Sci Int. 2020 Jul;312:110333. doi: 10.1016/j.forsciint.2020.110333. Epub 2020 May 19.
The secondary screwworm, Cochliomyia macellaria (Fabricius) (Diptera: Calliphoridae), is a carrion-breeding species of veterinary, medical, and forensic importance. It is very abundant in the Nearctic and Neotropical regions and is one of the most common colonizers of vertebrate remains in the southern United States. Therefore, it is of great evidential value in estimating the minimum time of colonization (TOC) of remains related to forensic investigations. So far, studies have investigated the effects of several biotic and abiotic factors on C. macellaria. However, no data on the specific impact of food source moisture on the larval development of this species are known to have been published. In this study, the effects of diet moisture on larval development time, larval length, and weight over time, as well as adult emergence and weight were investigated. C. macellaria was reared on diets prepared from freeze-dried bovine liver with varying moisture content (0.0, 33.0, 50.0, or 70.8%) at 25.6 °C, 77% RH, and 14:10 L:D. Frozen-thawed liver was used as a control. Water content was found to significantly impact immature development time and corresponding life-history traits, both within and among developmental stages of C. macellaria. This result indicates moisture content of the carrion source should be considered when estimating time of colonization and identification of immature stage of flies in forensic investigations. Furthermore, as diet moisture content significantly affected the dry mass of emerging adults, the mass of adults collected at a crime scene could provide useful information as it could be an indicator of the condition the remains were in during time of colonization, including the moisture content of the tissue.
次要嗜尸蝇 Cochliomyia macellaria（Fabricius）（双翅目：Calliphoridae）是一种腐肉性物种，具有兽医、医学和法医学的重要意义。它在近北极和新热带地区非常丰富，是美国南部最常见的脊椎动物遗骸殖民者之一。因此，它在估计与法医学调查相关的遗骸的最小殖民时间（TOC）方面具有重要的证据价值。到目前为止，已经有研究调查了多种生物和非生物因素对 C. macellaria 的影响。然而，据所知，尚无关于食物源水分对该物种幼虫发育具体影响的数据。在这项研究中，研究了饮食水分对幼虫发育时间、幼虫长度和体重随时间的变化以及成虫出现和体重的影响。C. macellaria 在水分含量分别为 0.0、33.0、50.0 或 70.8%的冷冻干燥牛肝制备的饮食中进行饲养，温度为 25.6°C、相对湿度为 77%，光照时间为 14:10。使用冷冻解冻的肝脏作为对照。结果发现水分含量显著影响 C. macellaria 的未成熟发育时间和相应的生命史特征，包括在各个发育阶段内和之间。这一结果表明，在估计殖民时间和鉴定法医调查中蝇类未成熟阶段时，应考虑腐肉源的水分含量。此外，由于饮食水分含量显著影响成年个体的干质量，因此在犯罪现场收集的成年个体的质量可以提供有用的信息，因为它可以作为指示遗骸在殖民期间的状况的指标，包括组织的水分含量。
