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1.
Front Insect Sci ; 4: 1385884, 2024.
Article in English | MEDLINE | ID: mdl-38947219

ABSTRACT

Calliphoridae are widespread globally and can inhabit a variety of habitats. In this brief report, we assessed the appeal of Chrysomya rufifacies to resources that were previously inhabited by Lucilia sericata and L. cuprina, both common carrion colonizers. Two hundred adult male and female (1:1) C. rufifacies were released under controlled conditions into clear plastic cages (45 x 45 x 45 cm) with four types of substrates: beef-liver; liver with 100 third-instar larvae of L. cuprina; (III) liver containing 100 third-instar larvae of L. sericata; and liver containing 100 third-instar larvae of C. rufifacies. Each substrate was left in place for 24 hours at the end of a tube connected to the cage, where sticky traps were positioned to capture flies that might have been attracted to a specific substrate. The results indicate variations in the attraction of flies to different types of livers colonized by larvae of various species. It is suggested that flies may have specific preferences depending on the species of larvae present in the substrate. The liver without larvae was the preferred choice, while beef liver with C. rufifacies larvae was the least attractive. Results of statistical tests indicated that there is independence between attractiveness preference and the presence of C. rufifacies flies. Although there is a trend among certain levels of the variables in the correspondence analysis, these relationships are not statistically significant. However, they indicate specific patterns of association between different groups of flies and species of larvae. This study demonstrated that C. rufifacies does not show reduced attraction to any of the resources. A tetrahedron olfactometer device has been used for the first time in a behavioral study of C. rufifacies flies. This may enable future studies to enhance the understanding of fly behavior.

2.
J Med Entomol ; 60(5): 931-943, 2023 09 12.
Article in English | MEDLINE | ID: mdl-37467349

ABSTRACT

Blow flies are of medical, sanitary, veterinary, and forensic importance. Their accurate taxonomic identification is essential for their use in applied research. However, neotropical fauna has not been completely studied or described, and taxa identification without the required training is a difficult task. Additionally, the current morphological keys are not fitting to all extant taxa. Molecular-based approaches are widely used to overcome these issues, including the standard 5' COI barcode fragment (~650 base pairs [bp]) for identification at the species level. Here, a shorter sequence of 5' COI fragment (~342 bp) was assessed for the identification of 28 blow fly species inhabiting the northwest of South America. One tree-based (the generalized mixed Yule-coalescent-GMYC) and 3 distance-based approaches (automatic barcode gap discover - ABGD, the best close match - BCM, and the nearest neighbor - NN) analyses were performed. Noticeably, the amplification and sequencing of samples that had been preserved for up to 57 years were successful. The tree topology assigned 113 sequences to a specific taxon (70% effectiveness), while the distance approach assigned to 95 (59% effectiveness). The short fragment allowed the molecular identification of 19 species (60% of neotropical species except for the Lucilia species and Hemilucilia semidiaphana). According to these findings, the taxonomic and faunistic considerations of the blow fly fauna were provided. Overall, the short fragment approach constitutes an optimal species confirmation tool for the most common blow flies in northwestern South America.


Subject(s)
Diptera , Animals , Diptera/genetics , DNA, Mitochondrial , Calliphoridae/genetics , Forensic Sciences , Electron Transport Complex IV/genetics , South America , DNA Barcoding, Taxonomic
3.
DNA Res ; 30(1)2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36370138

ABSTRACT

The New World Screwworm, Cochliomyia hominivorax (Calliphoridae), is the most important myiasis-causing species in America. Screwworm myiasis is a zoonosis that can cause severe lesions in livestock, domesticated and wild animals, and occasionally in people. Beyond the sanitary problems associated with this species, these infestations negatively impact economic sectors, such as the cattle industry. Here, we present a chromosome-scale assembly of C. hominivorax's genome, organized in 6 chromosome-length and 515 unplaced scaffolds spanning 534 Mb. There was a clear correspondence between the D. melanogaster linkage groups A-E and the chromosomal-scale scaffolds. Chromosome quotient (CQ) analysis identified a single scaffold from the X chromosome that contains most of the orthologs of genes that are on the D. melanogaster fourth chromosome (linkage group F or dot chromosome). CQ analysis also identified potential X and Y unplaced scaffolds and genes. Y-linkage for selected regions was confirmed by PCR with male and female DNA. Some of the long chromosome-scale scaffolds include Y-linked sequences, suggesting misassembly of these regions. These resources will provide a basis for future studies aiming at understanding the biology and evolution of this devastating obligate parasite.


Subject(s)
Myiasis , Screw Worm Infection , Animals , Male , Female , Cattle , Calliphoridae , Drosophila melanogaster , Myiasis/veterinary , Screw Worm Infection/veterinary , Chromosomes
4.
J Med Entomol ; 59(4): 1177-1181, 2022 07 13.
Article in English | MEDLINE | ID: mdl-35445274

ABSTRACT

Forensic Entomology uses arthropods to aid in legal investigations. This study checked the biological response of Chrysomya putoria pupae to submersion in fresh water for up to 6 d, evaluating the critical submersion time, survival rate, and development time of the flies. Adults were collected using fish baits in two typical traps. Seven hundred and twenty fourth-generation pupae with 2 d of development were used and separated into submergence intervals: 24, 48, 72, 96, 120, and 144 h. An additional 120 pupae were used as a control. Each treatment was done in triplicate, consisting of 40 pupae distributed in four tulle-sealed test tubes containing 10 pupae each. All tubes of each treatment were co-adhered in test tube racks and were submerged in mineral water in a container with constant oxygenation, except those of the control group, which were not submerged. The tubes were removed from the water according to their respective submersion interval, until 144 h was completed. The control group had a survival rate of 90%, while the 24-h treatment had 85% and the 48-h treatment had 35.8%. The critical submersion time for pupae was 72 h, with 100% mortality by 144 h. The average development time for the control group was 3.2 d, while the 24- and 48-h treatments developed in 4.3 and 6.3 d, respectively. The longer the individuals were submerged, the lower the survival rate was, while the development time increased. The data obtained in this study have potential in applications to estimate the interval of submersion of a cadaver.


Subject(s)
Diptera , Animals , Calliphoridae , Diptera/physiology , Fresh Water , Immersion , Larva , Pupa
5.
J Med Entomol ; 59(1): 147-161, 2022 01 12.
Article in English | MEDLINE | ID: mdl-34698350

ABSTRACT

Studies under constant temperatures are the most common to estimate the Postmortem Interval (PMI). It is imperative that forensic sciences have data from studies carried out in the field. Therefore, this work aims to: (1) evaluate the parameters (weight, length, development time) associated with the life cycles of Lucilia ochricornis (Wiedemann) (Diptera: Calliphoridae) and Lucilia purpurascens (Walker) under experimental conditions in the field considering fluctuating temperatures, and (2) compare these results with those known and published by the same authors for cultures realized in the laboratory under constant temperatures; which will permit us to contrast the most widely used existing methodologies for forensic application in estimating the minimum postmortem interval (PMImin). For each season of the year, cultures of both species were made in the field, collecting information on temperature, humidity, and photoperiod to perform laboratory cultures, later comparing: development time, length, weight, and Accumulated Degree-Hours (ADH) in both types of cultures. Methods for estimating the PMI were obtained and validated with the information of the cultures grown in the field. The two types of cultures showed differences between each other for both species. The forensic use methods to estimate PMI were enhanced and their precision increased when maximum larval length data were used, and it was also concluded that feeding larval stages are the most accurate to be used in making estimates because the larva is growing. The estimation of the PMI through the use of necrophagous flies development remains reliable for obtaining the PMImin.


Subject(s)
Calliphoridae/physiology , Life History Traits , Animals , Argentina , Calliphoridae/growth & development , Cold Temperature , Female , Forensic Entomology , Hot Temperature , Larva/growth & development , Larva/physiology , Male , Pupa/growth & development , Pupa/physiology , Seasons , Species Specificity , Temperature
6.
Microsc Res Tech ; 85(1): 149-155, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34331401

ABSTRACT

Brevibacillus laterosporus has entomopathogenic potential against several orders of insects and its wide bioactivity is associated with a variety of strain-specific molecules. In order to avoid the use of synthetic insecticides, along with the need to control insect pests, microbial control has been widely used. Muscoid dipterans are known for their medical-veterinary and sanitary importance, and synanthropy. The enormous biotechnological potential of B. laterosporus has been demonstrated, but there are still few studies with muscoid dipterans. The aim of the study was to verify the mortality of B. laterosporus NRS590 on synanthropic flies and to characterize its different cell stages ultrastructurally. The flies were collected from garbage bins and the colonies were adapted to the laboratory conditions. Bioassays with neo larvae were carried out from the bacterial growth in the phases: vegetative (6 hr), sporangium (20 hr), and free spores (44 hr). An aliquot of each phase was collected for Transmission (TEM) and Scanning Electron Microscopy (SEM). The effectiveness of NRS590 was observed in the sporulation phase, where the corrected mortality was 83.3, 85.1, and 99% for Chrysomya megacephala, Chrysomya putoria, and Musca domestica, respectively. The parasporal body was observed in detail on the entire spore surface. Although our knowledge of this bacterium is growing, it remains to be determined the real virulence factors responsible for the wide entomopathogenic activity observed on muscoid dipterans. Therefore, this study can provide subsidies for the improvement of efficient and safe microbial control techniques for the environment and living beings.


Subject(s)
Brevibacillus , Diptera , Animals , Larva , Virulence
7.
Pathog Dis ; 79(6)2021 08 10.
Article in English | MEDLINE | ID: mdl-34347083

ABSTRACT

Leishmaniasis is a neglected tropical disease that affects millions of people around the world. Larval excretion/secretion (ES) of the larvae of flies of the Calliphoridae family has microbicidal activity against Gram-positive and Gram-negative bacteria, in addition to some species of Leishmania. Our study aimed at assessing the in vitro efficacy of Lucilia cuprina larval ES against the promastigote and amastigote forms of Leishmania amazonensis, elucidating possible microbicidal mechanisms and routes of death involved. Larval ES was able to inhibit the viability of L. amazonensis at all concentrations, induce morphological and ultrastructural changes in the parasite, retraction of the cell body, roughness of the cytoplasmic membrane, leakage of intracellular content, ROS production increase, induction of membrane depolarization and mitochondrial swelling, the formation of cytoplasmic lipid droplets and phosphatidylserine exposure, thus indicating the possibility of apoptosis-like death. To verify the efficacy of larval ES on amastigote forms, we performed a phagocytic assay, measurement of total ROS and NO. Treatment using larval ES reduced the percentage of infection and the number of amastigotes per macrophage of lineage J774A.1 at all concentrations, increasing the production of ROS and TNF-α, thus indicating possible pro-inflammatory immunomodulation and oxidative damage. Therefore, treatment using larval ES is effective at inducing the death of promastigotes and amastigotes of L. amazonensis even at low concentrations.


Subject(s)
Antiprotozoal Agents/pharmacology , Calliphoridae/chemistry , Larva/chemistry , Leishmania/drug effects , Leishmaniasis/therapy , Animals , Biological Therapy/methods , Bodily Secretions/chemistry , Cell Death/drug effects , Cell Line , Cell Membrane/drug effects , Cell Survival/drug effects , Chlorocebus aethiops , Humans , Leishmania/metabolism , Membrane Potential, Mitochondrial/drug effects , Reactive Oxygen Species/metabolism , Vero Cells
8.
Acta Trop ; 222: 106052, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34273305

ABSTRACT

In most species, several factors like time of emergence, age at maturation, reproductive life span, survival of males and females, mating behavior, differential resource use, and migration patterns may affect the adult sex ratio. Anthropogenic landscape transformation is known to change diversity, favoring colonization by exotic species but other populational parameters, such as the sex ratio, have not been assessed. The aim of the present study was to describe the sex-ratio patterns of adult necrophagous blow flies captured using carrion-baited traps along habitats representing different levels of human impact. We describe the sex bias for four species: the exotic Chrysomya albiceps, Chrysomya megacephala, Chrysomya putoria, and the native Cochliomyia macellaria. Three types of habitats were selected: highly anthropized (urbanized), moderately anthropized (rural), and native forest (natural) within a humid subtropical ecoregion in Northeastern Argentina. We found an overall trend to female bias among the four species when considering the total number of each sex. However, our study showed a changing sex-ratio pattern along the gradient of human influence. Our results indicate that a higher likelihood of trapping more males in unsuitable habitats seems to be widespread among blow flies. Urban exploiters, such as Ch. megacephala and Ch. putoria, locally shifted their trends, becoming male-biased in natural habitats. The opposite trend was detected in the urban avoider Co. macellaria (which shifted to male-biased in urban habitats). The exception was Ch. albiceps, whose sex proportion did not shift to a male-biased sex ratio. The results of this study highlight the changing sex-ratio patterns displayed by Calliphoridae in response to different conditions along a human-influence gradient. The biological traits and underlying mechanisms promoting the intraspecific changes of the sex ratio are discussed.


Subject(s)
Calliphoridae , Ecosystem , Sex Ratio , Animals , Argentina , Female , Forests , Humans , Male
9.
Forensic Sci Int ; 324: 110827, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34030003

ABSTRACT

Sarcosaprophagous flies (Diptera) rank among the most common insects associated with human-transformed environments all over the world. Synanthropic species of the families Calliphoridae, Muscidae, Sarcophagidae and Phoridae, in particular, have tremendous forensic importance due to their ability to colonize human cadavers and thus provide information on minimum post-mortem interval. Recently, cases of flies colonizing cadavers inside buildings of different heights drew attention to the vertical dispersal abilities of these flies, a subject that has received little attention. We investigated the vertical distribution of sarcosaprophagous flies in an urban environment, using uninhabited buildings as experimental models in Northeastern Brazil. To assess the vertical stratification of flies, one in every three floors of nine buildings was sampled using traps baited with bovine spleen, from the ground to the 27th floor. Calliphoridae was the most abundant family (52.9%), followed by Muscidae (41.2%), Sarcophagidae (3.2%) and Phoridae (2.7%). Most of the insects were collected at ground level (78.8%), with a decreasing abundance registered on the higher floors. Nevertheless, adults of the four families tested here were able to reach substrates as high as the 15th floor, which corresponds to approximately 48 m in height. Regarding calliphorids, seven species were identified, of which Chrysomya albiceps (30.4%) and C. megacephala (68.3%) were the most abundant. This is, to our knowledge, the first detailed, replicated study on vertical resource localization of sarcosaprophagous flies.


Subject(s)
Built Environment , Diptera/physiology , Feeding Behavior , Postmortem Changes , Animals , Brazil , Cities , Forensic Entomology , Humans
10.
Pap. avulsos Zool. ; 61: e20216101, 2021. mapas, graf, tab
Article in English | VETINDEX | ID: vti-765668

ABSTRACT

Cities in northeastern Brazil experience extreme rates of unsolved homicides, a situation that stimulates innovative procedures in the police work, such as forensic entomology. We surveyed necrophagous insects associated with carrion in a city exposed to high rates of homicides in Northeastern Brazil. The experiments were carried out in a rainforest fragment located in Recife, State of Pernambuco. Two pig carcasses were used as models, one in the dry and the other in the rainy season. The collection of adults was performed daily until the complete skeletonization of the carcasses. At least 32 Diptera species from the families Calliphoridae, Muscidae, Sarcophagidae, Fanniidae, Phoridae, Anthomyiidae, Piophilidae, and Stratiomyidae were registered, some of which have been previously documented on cadavers. A high richness of Diptera species was registered in all stages of decomposition. A strong overlap in the occurrence of most species was observed, which invalidates a defined entomological succession on the carcasses. Two species stood out in terms of abundance: Ophyra chalcogaster (Muscidae) and Chrysomya albiceps (Calliphoridae). The ubiquity of Hemilucilia semidiaphana (Calliphoridae) seems to confirm its preference for forest fragments exposed to low anthropogenic action. Our data contribute to expand the knowledge on the geographical distribution of forensically relevant species in the region and confirm the rapid dissemination of invasive Chrysomya species in forested areas.(AU)


Subject(s)
Animals , Diptera/classification , Biodiversity , Meat , Swine
11.
Parasitol Res ; 120(1): 1-7, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33068150

ABSTRACT

The Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae) has a worldwide distribution and is considered of medical and veterinary importance. Its synanthropic behavior combined with the visitation of decaying organic matter allows it to mechanically transmit pathogens to human and animals. Pyrethroids are widely used pesticides, effective in low doses against a broad spectrum of insects. Our objective was to evaluate the action of K-Othrine® on the post-embryonic development of C. megacephala. First instar larvae were exposed to different concentrations of K-Othrine® (3.75 × 10-5 g a.i/mL (low), 7.5 × 10-5 g a.i/mL (intermediate low), 1.125 × 10-4 g a.i/mL (intermediate), 1.5 × 10-4 g a.i/mL (intermediate high), and 2.5 × 10-4 g a.i/mL (high)) mixed into artificial diets and a control with no pesticide. We measured weight, time of development, sex ratio, larval and pupal mortality, and esterase patterns. The mean weight values at intermediate low and intermediate concentrations were significantly lower compared with the control; additionally, the development time was delayed compared with the control. The larval and pupal mortality differed among the treatments. The larvae had six esterase regions, which altered its relative activity at 48 h and 72 h after insecticide ingestion. Further studies must investigate the effects of different insecticides on the post-embryonic development of C. megacephala.


Subject(s)
Calliphoridae/drug effects , Insecticides/pharmacology , Larva/drug effects , Nitriles/pharmacology , Pupa/growth & development , Pyrethrins/pharmacology , Animals , Calliphoridae/growth & development , Female , Humans , Pest Control/methods , Sex Ratio
12.
Genomics ; 113(1 Pt 2): 699-706, 2021 01.
Article in English | MEDLINE | ID: mdl-33022358

ABSTRACT

The Oestroidea superfamily is characterized by the diversity of feeding preferences among closely-related species; these flies are saprophagous, obligate parasites, or facultative parasites. We used gene expression and coding sequence data from five species (Cochliomyia hominivorax, Chrysomya megacephala, Lucilia cuprina, Dermatobia hominis, and Oestrus ovis) to identify underlying genetic differences involved in the diverse lifestyles. We tested whether 1287 orthologs have different expression and evolutionary constraints under different scenarios. We found two up-regulated genes; one in species causing cutaneous myiasis that is involved in iron transportation/metabolization (ferritin), and another in species causing traumatic myiasis that responds to reduced oxygen levels (anoxia up-regulated-like). Our evolutionary analysis showed a similar result. In the Co. hominivorax branch, we found one gene with the same function as ferritin that may be evolving under positive selection, spook. This is the first step towards understanding origins and evolution of parasitic strategy diversity in Oestroidea.


Subject(s)
Calliphoridae/genetics , Evolution, Molecular , Feeding Behavior , Insect Proteins/genetics , Animals , Calliphoridae/pathogenicity , Calliphoridae/physiology , Ferritins/genetics , Ferritins/metabolism , Humans , Insect Proteins/metabolism , Iron/metabolism , Myiasis/parasitology
13.
Pathog Dis, v. 79, n. 6, ago. 2021
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3917

ABSTRACT

Leishmaniasis is a neglected tropical disease that affects millions of people around the world. Larval excretion/secretion (ES) of the larvae of flies of the Calliphoridae family has microbicidal activity against Gram-positive and Gram-negative bacteria, in addition to some species of Leishmania. Our study aimed at assessing the in vitro efficacy of Lucilia cuprina larval ES against the promastigote and amastigote forms of Leishmania amazonensis, elucidating possible microbicidal mechanisms and routes of death involved. Larval ES was able to inhibit the viability of L. amazonensis at all concentrations, induce morphological and ultrastructural changes in the parasite, retraction of the cell body, roughness of the cytoplasmic membrane, leakage of intracellular content, ROS production increase, induction of membrane depolarization and mitochondrial swelling, the formation of cytoplasmic lipid droplets and phosphatidylserine exposure, thus indicating the possibility of apoptosis-like death. To verify the efficacy of larval ES on amastigote forms, we performed a phagocytic assay, measurement of total ROS and NO. Treatment using larval ES reduced the percentage of infection and the number of amastigotes per macrophage of lineage J774A.1 at all concentrations, increasing the production of ROS and TNF-α, thus indicating possible pro-inflammatory immunomodulation and oxidative damage. Therefore, treatment using larval ES is effective at inducing the death of promastigotes and amastigotes of L. amazonensis even at low concentrations.

14.
Pap. avulsos zool ; 61: e20216101, 2021. map, graf, tab
Article in English | VETINDEX | ID: biblio-1487400

ABSTRACT

Cities in northeastern Brazil experience extreme rates of unsolved homicides, a situation that stimulates innovative procedures in the police work, such as forensic entomology. We surveyed necrophagous insects associated with carrion in a city exposed to high rates of homicides in Northeastern Brazil. The experiments were carried out in a rainforest fragment located in Recife, State of Pernambuco. Two pig carcasses were used as models, one in the dry and the other in the rainy season. The collection of adults was performed daily until the complete skeletonization of the carcasses. At least 32 Diptera species from the families Calliphoridae, Muscidae, Sarcophagidae, Fanniidae, Phoridae, Anthomyiidae, Piophilidae, and Stratiomyidae were registered, some of which have been previously documented on cadavers. A high richness of Diptera species was registered in all stages of decomposition. A strong overlap in the occurrence of most species was observed, which invalidates a defined entomological succession on the carcasses. Two species stood out in terms of abundance: Ophyra chalcogaster (Muscidae) and Chrysomya albiceps (Calliphoridae). The ubiquity of Hemilucilia semidiaphana (Calliphoridae) seems to confirm its preference for forest fragments exposed to low anthropogenic action. Our data contribute to expand the knowledge on the geographical distribution of forensically relevant species in the region and confirm the rapid dissemination of invasive Chrysomya species in forested areas.


Subject(s)
Animals , Biodiversity , Meat , Diptera/classification , Swine
15.
Article in English | LILACS-Express | VETINDEX | ID: biblio-1487415

ABSTRACT

Abstract Cities in northeastern Brazil experience extreme rates of unsolved homicides, a situation that stimulates innovative procedures in the police work, such as forensic entomology. We surveyed necrophagous insects associated with carrion in a city exposed to high rates of homicides in Northeastern Brazil. The experiments were carried out in a rainforest fragment located in Recife, State of Pernambuco. Two pig carcasses were used as models, one in the dry and the other in the rainy season. The collection of adults was performed daily until the complete skeletonization of the carcasses. At least 32 Diptera species from the families Calliphoridae, Muscidae, Sarcophagidae, Fanniidae, Phoridae, Anthomyiidae, Piophilidae, and Stratiomyidae were registered, some of which have been previously documented on cadavers. A high richness of Diptera species was registered in all stages of decomposition. A strong overlap in the occurrence of most species was observed, which invalidates a defined entomological succession on the carcasses. Two species stood out in terms of abundance: Ophyra chalcogaster (Muscidae) and Chrysomya albiceps (Calliphoridae). The ubiquity of Hemilucilia semidiaphana (Calliphoridae) seems to confirm its preference for forest fragments exposed to low anthropogenic action. Our data contribute to expand the knowledge on the geographical distribution of forensically relevant species in the region and confirm the rapid dissemination of invasive Chrysomya species in forested areas.

16.
Article in English | MEDLINE | ID: mdl-32937878

ABSTRACT

In the One Health scenario, a deep understanding of the dynamics potentially threatening the development and implementation of useful pest and vector management tools is of key importance. The New World screwworm fly, Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae), is characterized by a wide host range. It acts as an important agent of myiasis in humans and warm-blooded animals in the Neotropics, and has been eliminated from a wide region through genetic methods. Of note, Serebrovsky had already proposed in 1940 the principles of autocidal control by the translocation of segments between two chromosomes, but his work was negated by Lysenko, based on the negation of Mendelian genetics. This entomological case study emphasizes the danger of politics interfering with science, a still contemporary hot issue. The negation of global warming or current pandemics are further examples of this noxious influence.


Subject(s)
Diptera , Myiasis , Politics , Science , Animals , Animals, Domestic , Diptera/pathogenicity , Humans , Myiasis/epidemiology , Public Health
17.
J Forensic Sci ; 65(5): 1594-1600, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32315450

ABSTRACT

Field studies in forensic entomology seem to assume that a cadaver is a resource equally accessible to flies, irrespective of the species' size, behavior, and sensorial capacity. We aimed to challenge this assumption by experimentally manipulating baited traps in order to test whether the accessibility to decomposing baits is related to the following: (i) the diversity of necrophagous dipterans; (ii) the body size of adults; and (iii) the female sexual maturity stage. The experiment was performed in a rainforest fragment in Northeastern Brazil, in an area characterized by high levels of homicides. Traps baited with decomposing chicken liver had three levels of access: easy (six openings on the trap), intermediate (three), and difficult (one). A total of 750 adults of Calliphoridae, Fanniidae, Muscidae, Phoridae, and Sarcophagidae were collected. Of the 18 species recorded, Megaselia scalaris was the most abundant (46.8%) followed by Lucilia eximia (29.7%) and Chrysomya megacephala (9.8%). The number of species increased significantly with the accessibility level, but overall abundance did not differ, as a consequence of the numerical dominance of M. scalaris. A strong female bias (>91%) was observed in all traps. For Calliphoridae specimens, 90% of the females caught in traps under intermediate and difficult access were sexually mature. By empirically demonstrating that limitation of access and exclusion of visual stimuli do not deter several dipteran species from reaching a substrate, we expand the knowledge on the factors that can shape the colonization of concealed human cadavers, including variables such as insect size and stage of sexual maturity.


Subject(s)
Diptera , Feeding Behavior , Postmortem Changes , Animals , Brazil , Female , Forensic Entomology , Male , Sex Distribution , Sexual Maturation
18.
Revista Brasileira de Zoociências (Online) ; 21(1): 1-11, 2020. tab, graf
Article in English | VETINDEX | ID: biblio-1494772

ABSTRACT

Este trabalho foi realizado por alunos do Ensino Médio do campus Niterói do Colégio Pedro II, no período de 2015 a 2016, com o apoio do Programa de incentivo a Projetos de Pesquisa de Iniciação Científica Júnior da Pró-Reitoria de PósGraduação, Pesquisa, Extensão e Cultura do Colégio Pedro II (PROPGPEC). Teve o objetivo de conhecer a entomofauna de Calliphoridae (Diptera) presente no bairro do Barreto, Niterói, RJ, Brasil, quantificando as espécies predominantes da localidade. Assim, contribuiu para que os alunos vivenciassem a aplicação do método científico. As moscas foram capturadas no campus Niterói do Colégio Pedro II, através de coletas semanais, com auxílio de armadilhas cilíndricas de metal, que continham sardinha como isca. Foram capturados, ao todo, 1.308 exemplares, preservados em álcool e, posteriormente identificados com o auxílio de chaves dicotômicas apropriadas. Chrysomya Megachephala (Fabricius, 1794) foi a espécie mais abundante. De uma forma geral, as espécies do gênero Chrysomya (Robineau-Desvoidy, 1830) mostram forte associação com o ambiente modificado pelo homem. Devido à grande capacidade competitiva com espécies autóctones e à importância médico-veterinária que apresenta, a continuidade dos estudos populacionais dessa espécie, ao longo do território nacional, pode contribuir com programas de controle e combate desses insetos.


This study was carried out by a group of high school students of Colegio Pedro II, campus Niterói, from 2015 through 2016 and was supported by the Junior Scientific Initiation Program supervised by the Dean of Graduate Studies, Research, Extension and Culture of this same institution. The purpose of the program is to familiarize students with scientific research methods and analytical tools. The research presented in this article aimed at knowing the fauna of Calliphoridae (Diptera) in Barreto, a borough in the city of Niterói, Rio de Janeiro, Brazil, focusing on the quantity of predominant species found in the area. Flies were weekly captured at Colégio Pedro II campus Niterói, with the help of a cylindrical metal trap, containing sardine baits. The data collected consisted of 1308 specimens, which were properly identified using a stereoscopic microscope and properly dichotomous keys. Chrysomya megacephala (Fabricius, 1794) was the most abundant species collected. Chrysomya species (Robineau-Desvoidy, 1830) usually have a strong connection to the environment modified by man. They compete with native species and they have a medical and veterinary significant role. It is important that studies continue to be carried out across the Brazilian territory so that they could help create programs to control and fight these insects.


Subject(s)
Animals , Demography , Diptera/classification , Seasons
19.
R. bras. Zoo. ; 21(1): 1-11, 2020. tab, graf
Article in English | VETINDEX | ID: vti-31644

ABSTRACT

Este trabalho foi realizado por alunos do Ensino Médio do campus Niterói do Colégio Pedro II, no período de 2015 a 2016, com o apoio do Programa de incentivo a Projetos de Pesquisa de Iniciação Científica Júnior da Pró-Reitoria de PósGraduação, Pesquisa, Extensão e Cultura do Colégio Pedro II (PROPGPEC). Teve o objetivo de conhecer a entomofauna de Calliphoridae (Diptera) presente no bairro do Barreto, Niterói, RJ, Brasil, quantificando as espécies predominantes da localidade. Assim, contribuiu para que os alunos vivenciassem a aplicação do método científico. As moscas foram capturadas no campus Niterói do Colégio Pedro II, através de coletas semanais, com auxílio de armadilhas cilíndricas de metal, que continham sardinha como isca. Foram capturados, ao todo, 1.308 exemplares, preservados em álcool e, posteriormente identificados com o auxílio de chaves dicotômicas apropriadas. Chrysomya Megachephala (Fabricius, 1794) foi a espécie mais abundante. De uma forma geral, as espécies do gênero Chrysomya (Robineau-Desvoidy, 1830) mostram forte associação com o ambiente modificado pelo homem. Devido à grande capacidade competitiva com espécies autóctones e à importância médico-veterinária que apresenta, a continuidade dos estudos populacionais dessa espécie, ao longo do território nacional, pode contribuir com programas de controle e combate desses insetos.(AU)


This study was carried out by a group of high school students of Colegio Pedro II, campus Niterói, from 2015 through 2016 and was supported by the Junior Scientific Initiation Program supervised by the Dean of Graduate Studies, Research, Extension and Culture of this same institution. The purpose of the program is to familiarize students with scientific research methods and analytical tools. The research presented in this article aimed at knowing the fauna of Calliphoridae (Diptera) in Barreto, a borough in the city of Niterói, Rio de Janeiro, Brazil, focusing on the quantity of predominant species found in the area. Flies were weekly captured at Colégio Pedro II campus Niterói, with the help of a cylindrical metal trap, containing sardine baits. The data collected consisted of 1308 specimens, which were properly identified using a stereoscopic microscope and properly dichotomous keys. Chrysomya megacephala (Fabricius, 1794) was the most abundant species collected. Chrysomya species (Robineau-Desvoidy, 1830) usually have a strong connection to the environment modified by man. They compete with native species and they have a medical and veterinary significant role. It is important that studies continue to be carried out across the Brazilian territory so that they could help create programs to control and fight these insects.(AU)


Subject(s)
Animals , Diptera/classification , Demography , Seasons
20.
J Forensic Sci ; 64(6): 1720-1725, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31674674

ABSTRACT

One of the most important contributions of forensic entomology is to assist criminal expertise to determine the postmortem interval, which depends on the duration of the immature stages of insects of forensic interest. On the other hand, the time of development of the different stages varies according to the species; therefore, its identification is essential. Currently, few studies have investigated the use of cuticular hydrocarbons, and none regarding fatty acids, as complementary taxonomic tools to expedite species identification. Therefore, we evaluated whether cuticular hydrocarbons together with fatty acids of eggs of flies of the family Calliphoridae, main group of forensic interest, can be used to distinguish species. The analyses were performed by chromatographic techniques. The results show that there are significant differences between the composition of cuticular hydrocarbons and fatty acids between species and, therefore, they can be used to provide a complementary taxonomic tool to expedite the forensic expertise.


Subject(s)
Diptera/metabolism , Fatty Acids/metabolism , Hydrocarbons/metabolism , Ovum/metabolism , Animal Scales/metabolism , Animals , Chromatography , Discriminant Analysis , Entomology/methods , Forensic Sciences , Species Specificity
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