Larvicidal Activity of Selected Plant Extracts Against the Screwworm Fly Chrysomya Albiceps

Myiasis is a kind of parasitic disease originating from the invasion of tissues of domestic animals by dipteran larvae. Chrysomya albicebs is a type of screwworm fly spread in the tropical areas and known to cause myiasis among live human and animals leading to health problems and high economic losses to dairy producers. Management and control of this pest is needed to overcome these losses. Nowadays, natural botanical products have been increasingly investigated as controlling agents against insects of medical and veterinary importance. This research was designed to evaluate the larvicidal effect of the total extracts of three plants, Ficus palmate, Juniperus procera and Nerium oleander against screwworm fly Chrysomya albiceps. The plants leaves were extracted with organic solvents mixture methanol : chloroform (1:1) and were tested against the second larval instar of C. albiceps using feeding and dipping methods. The extracts caused larval mortalities in the order of F. palmate> N. oleander > J. procer with IC50 values of 15.97, 33.73 and 37.24, respectively using feeding method and in the order N. oleander > F. palmate > J. procera with IC50 values of 43.12, 47.41 and 73.39, respectively using dipping method. It is concluded that the F. palmate followed by N. oleander and J. procera are candidates to use in controlling the larvae of myiasis-caused fly C. albiceps.

Development of Chrysomya albiceps (Wiedemann, 1819) (Diptera: Calliphoridae) from the Jazan region of Southwest Saudi Arabia under different laboratory temperatures: applications in forensic entomology

Background Chrysomya albiceps (Wiedemann, 1819) (blowflies), family Calliphoridae, is important in forensic entomology, where the minimum and maximum postmortem intervals (PMI) are estimated on the basis of the developmental stages of Diptera larvae that consume dead tissue. The present study was designed to estimate the effects of different ambient temperatures (20, 25, and 30 °C) under controlled laboratory conditions on the developmental stages of C. albiceps from the Jazan region, Saudi Arabia. Results The present study showed that the larval body weight and length were significantly increased when larvae were reared at 30 °C compared with corresponding values at 24 h, 48 h, and 72 h at rearing temperatures of 20 °C and 25 °C; however, the weight and length were significantly decreased compared with corresponding values at 96 h at 20 °C and 25 °C. The pupation time was inversely related to the rearing temperature, occurring at 144, 124, and 120 h at rearing temperatures of 20 °C, 25 °C, and 30 °C, respectively. The pupal weight and length were significantly increased in larvae reared at 30 °C compared with those reared at 20 °C and 25 °C. At 20 °C, 25 °C, and 30 °C, larval durations of 5.00, 5.00, and 4.00 days were recorded, respectively. Pupae and adults showed gradual decreases in life stage durations, at 6.00, 5.30, and 4.80 days in pupae and 20.00, 18.70, and 16.90 days in adults, with increasing rearing temperatures. Average adult longevity at 30 °C (194.40 h) was significantly less than adult longevity at 20 °C (216.00 h) and 25 °C (204.60 h). The results showed an inverse relation between durations of developmental stages and rearing temperatures. Conclusions Insect laboratory colonization for the determination of biological characteristics of insects is economically viable for forensic entomology and as a technique for evaluating insect evidence.

Temporal dynamic and key species of the sarcosapropha­gous entomofauna in a Mediterranean natural environment

Los insectos pueden detectar la presencia de un cadáver a gran distancia, colonizándolo rápidamente y siendo los primeros en explotar este recurso. La composición y dinámica de la comunidad, junto con su presencia en un lugar específico, son clave para su posterior aplicación forense. Por este motivo, se estudió la fauna entomosarcosaprófaga asociada a un cadáver en una zona montañosa de la provincia de Murcia (SE, España). Las especies Chrysomya albiceps, Calliphora vicina y C. vomitoria fueron las especies más valiosas como indicadores estacionales. Estas especies, junto con Dermestes frischii, Camponotus sylvaticus y la superfamilia Chalcidoidea, definen un patrón claro de colonización que varía según la estación del año. Finalmente, la especies Iberoformica subrufa pueden tener valor potencial como indicador de hábitat del área estudiada. Insects can detect the presence of a cadaver at a great distance, colonizing it rapidly and being the first to exploit this resource. Its composition and dynamics, together with its presence in a specific location, are key to its subsequent forensic application. For this reason, it was studied the entomosarcosaprophagous fauna associated with a carcass in a wild mountainous area of the province of Murcia (SE, Spain). The species Chrysomya albiceps, Calliphora vicina and C. vomitoria were the most valuables species as seasonal indicators. These species, together with Dermestes frischii, Camponotus sylvaticus and those of the Chalcidoidea superfamily, define a clear pattern of colonization that varies according to the season of the year. Finally, the species Iberoformica subrufa may be of potential use as habitat indicator of the studied area.

Muscidae e Calliphoridae (Diptera, Brachycera) associados à decomposição cadavérica no noroeste do Paraná

O presente trabalho teve como objetivo listar quais são os dípteros necrófagos na região noroeste do Paraná. As informações fazem parte de um projeto, aprovado no comitê de ética em pesquisa de animais, em desenvolvimento no IFPR Campus Umuarama. Durante o estudo, um cadáver de suíno com o peso aproximado de 10 kg foi utilizado como substrato, o qual foi colocado em uma gaiola com uma tela, para impedir a entrada de vertebrados necrófagos. A coleta dos insetos foi realizada por meio de uma armadilha modificada. A gaiola de metal que continha o substrato estava fixada no terreno do IFPR Campus Umuarama. Em relação aos insetos foram coletadas cinco espécies de Muscidae (Sarcopromusca pruna; Musca domestica; Hydrotaea aenescens; Sythesiomyia nudiseta e Stomoxys calcitrans) e seis espécies de Calliphoridae (Cochliomyia macellaria; Chrysomya albiceps; Chrysomya megacephala; Lucilia eximia; Lucilia cuprina e Hemilucilia segmentaria). Os espécimes de Stomoxys calcitrans podem ter sido coletados devido à presença de gado de corte próximo ao local. O processo de decomposição se completou em seis dias, o que pode ser devido aos altos índices de temperatura e baixos índices de umidade observados no local. Nesse período foram observados quatro estágios: fresco; enfisematoso; coliquativo e esqueletização. Estes dados são importantes para a construção de um banco de dados de espécies de importância forense.

Effects of ante-mortem use of methadone on insect succession patterns

Background Evaluation of insect succession patterns is a scientific method to estimate the time elapsed since death. Several studies have shown that ante-mortem intake of opioids affect maggot growth rate. However, there are few published data that investigate the effect of ante-mortem opioid use on insect succession patterns. Therefore, the main purpose of this research was to investigate the effect of methadone on the succession patterns of insects on rabbit carcasses during the spring and winter of 2019. In the present study, the H-null hypothesis represents the dissimilarity between the successional waves of species from testing and control carcasses (H0: P: 0). Results During this study, 15 and 13 insect species were collected from carcasses during the spring and winter, respectively. The most dominant species during the both seasons were Chrysomya albiceps and Calliphora vicina. These two species preferred to lay eggs on the control carcasses earlier than the treated carcasses. Lucilia cuprina was observed only from the remains of untreated carcasses, while Saprinus chalcites and Necrobia rufipes were recorded only from the remains of treated rabbits. Samples indicate that 11.8% of the insects were members of the Coleoptera. Permutation analyzes based on the Mantel test were 0.647 ± 0.16 (P = 0.009) and 0.693 ± 0.16 (P = 0.003) for the similarity of the species between treated and untreated carcasses in the spring and winter, respectively. Permutation analyzes for the two most dominant fly species (Ch. albiceps and C. vicina) between the treated and untreated carcasses in the spring and winter were 0.515 ± 0.15 (P = 0.05) and 0.491 ± 0.14 (P = 0.09), respectively. Conclusion The results revealed that the overall pattern of insect succession was similar between the treated and untreated rabbit carcasses. However, the patterns of succession of Chrysomya albiceps and Calliphora vicina differed slightly between treated and untreated carcasses, and this could have an effect on the PMI min estimate.

Post-mortem Interval Estimation in a Forensic Case with Two Predatory Species: Chrysomya albiceps and Synthesiomyia nudiseta

A forensic case in which two facultative predatory species were found together on a human corpse is presented in this work. Second and third instar larvae of Synthesiomyia nudiseta (van der Wulp, 1883) (Diptera: Muscidae) and Chrysomya albiceps (Wiedemann, 1819) (Diptera: Calliphoridae) were collected from the dead body of a man on 14th November 2019, but puparia in the autopsy pictures were observed after, but not collected. The corpse was found on the terrace of the third floor of a building located in the town of Elche (SE Spain), and the pathologist confirmed the death as natural. The minimum post-mortem interval was estimated by the time to reach the length of the collected larvae or to reach the pupal developmental stage (in days and accumulated degree-days). In accordance with the influence of the predatory behaviour of each of these species on the developmental data of the other, as described in the existing literature, the effect of a hypothetical competition between both species on post-mortem interval was discussed.