RESUMO
With the potential to process the world's agricultural and food waste, provide sustainable fodder for livestock, aquaculture, and pet animals, as well as act as a source of novel biomolecules, the black soldier fly, Hermetia illucens, has been launched into the leading position within the insects as feed industry. Fulfilment of these goals, however, requires mass-rearing facilities to have a steady supply of neonate larvae, which in-turn requires an efficient mating process to yield fertile eggs; yet, little is known about adult reproductive behavior, nor what physiological factors lead to its emergence. Moreover, fertile egg production tends to be highly variable in colony. Therefore, this review brings together what is currently known of the organismal biology of H. illucens, compiling information on adult morphology, physiology, biogeography, genomics, and behavioral ecology. As a holistic synthesis, it highlights several directions of interest for research to follow.
Assuntos
Dípteros , Eliminação de Resíduos , Animais , Dípteros/fisiologia , Alimentos , Larva , BiologiaRESUMO
Black soldier fly (BSF; Hermetia illucens) is a promising insect species for food and feed production as its larvae can convert different organic waste to high-value protein. Selective breeding is one way to optimize production, but the potential of breeding is only starting to be explored and not yet utilized for BSF. To assist in monitoring a captive population and implementing a breeding program, genomics tools are imperative. We conducted whole genome sequencing of two captive populations separated by geographical distance - Denmark (DK) and Texas, USA (TX). Various population genetics analyses revealed a moderate genetic differentiation between two populations. Moreover, we observed higher inbreeding in the DK population, and the detection of a subpopulation within DK population aligned well with the recent foundation of the DK population from two captive populations. Additionally, we generated gene ontology annotation and variants annotation for wider potential applications. Our findings establish a robust marker set for research in population genetics, facilitating the monitoring of inbreeding and laying the groundwork for practical breeding programs for BSF.
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The increasing prevalence of antibiotic-resistant bacteria (ARB) from animal manure has raised concerns about the potential threats to public health. The bioconversion of animal manure with insect larvae, such as the black soldier fly larvae (BSFL, Hermetia illucens [L.]), is a promising technology for quickly attenuating ARB while also recycling waste. In this study, we investigated BSFL conversion systems for chicken manure. Using metagenomic analysis, we tracked ARB and evaluated the resistome dissemination risk by investigating the co-occurrence of antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), and bacterial taxa in a genetic context. Our results indicated that BSFL treatment effectively mitigated the relative abundance of ARB, ARGs, and MGEs by 34.9%, 53.3%, and 37.9%, respectively, within 28 days. Notably, the transferable ARGs decreased by 30.9%, indicating that BSFL treatment could mitigate the likelihood of ARG horizontal transfer and thus reduce the risk of ARB occurrence. In addition, the significantly positive correlation links between antimicrobial concentration and relative abundance of ARB reduced by 44.4%. Moreover, using variance partition analysis (VPA), we identified other bacteria as the most important factor influencing ARB, explaining 20.6% of the ARB patterns. Further analysis suggested that antagonism of other bacteria on ARB increased by 1.4 times, while nutrient competition on both total nitrogen and crude fat increased by 2.8 times. Overall, these findings provide insight into the mechanistic understanding of ARB reduction during BSFL treatment of chicken manure and provide a strategy for rapidly mitigating ARB in animal manure.
Assuntos
Dípteros , Esterco , Animais , Larva/genética , Esterco/análise , Galinhas/genética , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Dípteros/genética , Bactérias , Resistência Microbiana a Medicamentos , Genes Bacterianos , Antibacterianos/farmacologiaRESUMO
BACKGROUND: The black soldier fly (Hermetia illucens) is the most promising insect candidate for nutrient-recycling through bioconversion of organic waste into biomass, thereby improving sustainability of protein supplies for animal feed and facilitating transition to a circular economy. Contrary to conventional livestock, genetic resources of farmed insects remain poorly characterised. We present the first comprehensive population genetic characterisation of H. illucens. Based on 15 novel microsatellite markers, we genotyped and analysed 2862 individuals from 150 wild and captive populations originating from 57 countries on seven subcontinents. RESULTS: We identified 16 well-distinguished genetic clusters indicating substantial global population structure. The data revealed genetic hotspots in central South America and successive northwards range expansions within the indigenous ranges of the Americas. Colonisations and naturalisations of largely unique genetic profiles occurred on all non-native continents, either preceded by demographically independent founder events from various single sources or involving admixture scenarios. A decisive primarily admixed Polynesian bridgehead population serially colonised the entire Australasian region and its secondarily admixed descendants successively mediated invasions into Africa and Europe. Conversely, captive populations from several continents traced back to a single North American origin and exhibit considerably reduced genetic diversity, although some farmed strains carry distinct genetic signatures. We highlight genetic footprints characteristic of progressing domestication due to increasing socio-economic importance of H. illucens, and ongoing introgression between domesticated strains globally traded for large-scale farming and wild populations in some regions. CONCLUSIONS: We document the dynamic population genetic history of a cosmopolitan dipteran of South American origin shaped by striking geographic patterns. These reflect both ancient dispersal routes, and stochastic and heterogeneous anthropogenic introductions during the last century leading to pronounced diversification of worldwide structure of H. illucens. Upon the recent advent of its agronomic commercialisation, however, current human-mediated translocations of the black soldier fly largely involve genetically highly uniform domesticated strains, which meanwhile threaten the genetic integrity of differentiated unique local resources through introgression. Our in-depth reconstruction of the contemporary and historical demographic trajectories of H. illucens emphasises benchmarking potential for applied future research on this emerging model of the prospering insect-livestock sector.
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Dípteros , Ração Animal/análise , Animais , Demografia , Dípteros/genética , Genética Populacional , Humanos , LarvaRESUMO
Lincomycin fermentation residues (LFR) are the byproducts from the pharmaceutical industry, and contain high concentrations of antibiotics that could pose a threat to the environment. Here, we report that black soldier fly larvae (BSFL) and associated microbiota can effectively degrade LFR and accelerate the degradation of lincomycin in LFR. The degradation rate of lincomycin in LFR can reach 84.9% after 12 days of BSFL-mediated bioconversion, which is 3-fold greater than that accomplished with natural composting. The rapid degradation was partially carried out by the BSFL-associated microbiota, contributing 22.0% of the degradation in the final composts. Based on microbiome analysis, we found that the structure of microbiota from both BSFL guts and BSFL composts changed significantly during the bioconversion, and that several bacterial genera were correlated with lincomycin degradation. The roles of the associated microbiota in the degradation were further verified by the ability of two larval intestinal bacterial isolates and one bacterial isolate from BSFL composts to lincomycin degradation. The synergy between BSFL and the isolated strains resulted in a 2-fold increase in degradation compared to that achieved by microbial degradation alone. Furthermore, we determined that the degradation was correlated with the induction of several antibiotic resistant genes (ARGs) associated with lincomycin degradation in larval guts and BSFL composts. Moreover, the environmental conditions in the BSFL composts were found to be conducive to the degradation. In conclusion, these findings demonstrate that the BSFL-mediated bioconversion of LFR could effectively reduce residual lincomycin and that the associated microbiota play crucial roles in the process.
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Dípteros , Resíduos Industriais , Animais , Indústria Farmacêutica , Larva , LincomicinaRESUMO
Age determination of insects collected from vertebrate remains is an essential step in estimating time since colonization as related to the post-mortem interval. Long-established methods for making such estimates rely on determining age related to stage of development at the time of collection in relation to conditions experienced. However, such estimates are based on the completion of a stage of development. Methods allowing for more precise estimates of age (i.e., within a stage of development) are sorely needed. This study examined the potential of volatile organic compounds emitted by blow fly, Ch. rufifacies (Macquart), immatures to determine stage of development, which could potentially be used to estimate the age. Volatile organic compounds (VOCs) from the larval and pupal stages of Ch. rufifacies were collected by headspace solid-phase micro-extraction followed by gas chromatography-mass spectrometry (GC-MS). Analyses indicated 37 compounds shift quantitatively, as well as qualitatively, as the larvae and pupae age. Furthermore, compounds, such as 2-ethyl-1-hexanol, phenol, butanoic acid, hexadecanoic acid, octadecanoic acid, 2-methyl propanamide, and 2-methyl butanoic acid, serve as indicator compounds of specific stages within Ch. rufifacies development. This information could be important to determine if these compounds can be used in the field to predict the presence of certain developmental stages, in order to determine the potential of using volatile markers to estimate time of colonization.
Assuntos
Calliphoridae/química , Calliphoridae/crescimento & desenvolvimento , Entomologia Forense , Compostos Orgânicos Voláteis/análise , Animais , Cromatografia Gasosa-Espectrometria de Massas , Larva/química , Larva/crescimento & desenvolvimento , Pupa/química , Pupa/crescimento & desenvolvimento , Microextração em Fase SólidaRESUMO
The attraction and colonization of vertebrate remains by carrion-associated arthropods are processes largely governed by olfaction. As remains decompose, they emit a bouquet of volatile organic compounds (VOCs), which in part originate from endogenous and exogenous microbes surrounding the carcass or from the carcass itself. The composition and concentration of VOCs are influenced by the presence and abundance of microbial species and arthropods. Blowfly species, such as Cochliomyia macellaria, play a critical role in nutrient recycling and the decomposition process of carrion. Gas chromatography-mass spectroscopy analysis was used to identify and classify volatile emissions from insect-colonized (with C. macellaria) and uncolonized rat carcasses, as well as a standard Gainesville diet, over a 10-day period. There were significant differences in composition and abundance of compounds present in each treatment, with significant effects of time, and different compound composition between treatments. Notable indicator compounds included, but were not limited to, indole, dimethyl disulfide, and dimethyl trisulfide. A high compound richness, and a low compound diversity, was detected over the 10-day period. The indicator compounds detected across all treatments were found to be of microbial origin, highlighting the importance of microbes in decomposition processes and arthropod attraction to carrion. This study also discusses the significant impact of necrophagous arthropods to the VOC profile of carrion. The results of this study provide insight into the changes in decomposition VOCs over time, with an explanation of compounds in high concentration known to be attractive to carrion-colonizing arthropods.
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Restos Mortais/química , Calliphoridae , Entomologia Forense , Compostos Orgânicos Voláteis/análise , Animais , Restos Mortais/microbiologia , Cromatografia Gasosa-Espectrometria de Massas , Microbiota , Mudanças Depois da Morte , Ratos , Compostos Orgânicos Voláteis/classificaçãoRESUMO
BACKGROUND: The black soldier fly (Diptera: Stratiomyidae, Hermetia illucens) is renowned for its bioconversion ability of organic matter, and is the worldwide most widely used source of insect protein. Despite varying extensively in morphology, it is widely assumed that all black soldier flies belong to the same species, Hermetia illucens. We here screened about 600 field-collected and cultured flies from 39 countries and six biogeographic regions to test this assumption based on data for three genes (mitochondrial COI, nuclear ITS2 & 28S rDNA) and in order to gain insights into the phylogeography of the species. RESULTS: Our study reveals a surprisingly high level of intraspecific genetic diversity for the mitochondrial barcoding gene COI (divergences up to 4.9%). This level of variability is often associated with the presence of multiple species, but tested nuclear markers (ITS2 and 28S rDNA) were invariant and fly strain hybridization experiments under laboratory conditions revealed reproductive compatibility. COI haplotype diversity is not only very high in all biogeographic regions (56 distinct haplotypes in total), but also in breeding facilities and research centers from six continents (10 haplotypes: divergences up to 4.3%). The high genetic diversity in fly-breeding facilities is mostly likely due to many independent acquisitions of cultures via sharing and/or establishing new colonies from field-collected flies. However, explaining some of the observed diversity in several biogeographic regions is difficult given that the origin of the species is considered to be New World (32 distinct haplotypes) and one would expect severely reduced genetic diversity in the putatively non-native populations in the remaining biogeographic regions. However, distinct, private haplotypes are known from the Australasian (N = 1), Oriental (N = 4), and the Eastern Palearctic (N = 4) populations. We reviewed museum specimen records and conclude that the evidence for introductions is strong for the Western Palearctic and Afrotropical regions which lack distinct, private haplotypes. CONCLUSIONS: Based on the results of this paper, we urge the black soldier fly community to apply molecular characterization (genotyping) of the fly strains used in artificial fly-breeding and share these data in research publications as well as when sharing cultures. In addition, fast-evolving nuclear markers should be used to reconstruct the recent invasion history of the species.
Assuntos
Dípteros/metabolismo , Proteínas de Insetos/metabolismo , Mitocôndrias/metabolismo , Filogeografia , Animais , Cruzamento , Dípteros/genética , Dípteros/fisiologia , Variação Genética , Larva/metabolismo , ReproduçãoRESUMO
As global food demand is increasing along with human population growth, there is a greater need for alternative protein sources. Insect protein, especially the larvae of the black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae), has become a key approach for solving this issue in part due to its ability to convert organic waste into insect biomass with minimal resource (e.g., land, water) requirements. However, most information utilized to develop industrial production of this species is reliant on data generated from laboratory-scaled studies. Unfortunately, scaling these data to an industrial level potentially is not linear resulting in over, or under, estimating production. In this study, we compared selected life-history traits of larval black soldier fly produced at benchtop (e.g., 1 liter container with 614 larvae) and industrial scales (e.g., 29.5 liter container inoculated with 10,000 larvae). Larvae were provided a single feeding (2 g/larva) in each treatment. Significant differences in the mean larval weight (24.7%), survivorship (-28.2%), and biomass conversion (-2.7%) were determined between benchtop and industrial treatments. These results indicate larval number and the associated container size are important factors to consider when designing a black soldier fly factory. Furthermore, caution should be taken when applying data from laboratory studies to industrial scale production systems as the values potentially are not linear.
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Dípteros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Instalações Industriais e de Manufatura/organização & administração , Animais , Biodegradação Ambiental , Biorretroalimentação Psicológica , Biomassa , Peso Corporal , Características de História de Vida , Esterco , ResíduosRESUMO
Currently, sustainable utilisation, including recycling and valorisation, is becoming increasingly relevant in environmental management. The wastes bioconversion by the black soldier fly larva (BSFL) has two potential advantages: the larvae can convert the carbon and nitrogen in the biomass waste, and improve the properties of the substrate to reduce the loss of gaseous carbon and nitrogen. In the present study, the conversion rate of carbon, nitrogen and the emissions of greenhouse gases and NH3 during BSFL bio-treatment of food waste were investigated under different pH conditions. The results showed that the pH of the raw materials is a pivotal parameter affecting the process. The average wet weight of harvested BSFL was 13.26-95.28 mg/larva, with about 1.95-13.41% and 5.40-18.93% of recycled carbon and nitrogen from substrate at a pH from 3.0 to 11.0, respectively. Furthermore, pH is adversely correlated with CO2 emissions, but positively with NH3 emissions. Cumulative CO2, NH3, CH4 and N2O emissions at pH ranging from 3.0 to 11.0 were 88.15-161.11 g kg-1, 0.15-1.68 g kg-1, 0.19-2.62 mg kg-1 and 0.02-1.65 mg kg-1, respectively. Compared with the values in open composting, BSFL bio-treatment of food waste could lead greenhouse gas (especially CH4 and N2O) and NH3 emissions to decrease. Therefore, a higher pH value of the substrate can increase the larval output and help the mitigation of greenhouse gas emissions.
Assuntos
Gases de Efeito Estufa , Eliminação de Resíduos , Simuliidae , Animais , Carbono , Dióxido de Carbono , Alimentos , Metano , NitrogênioRESUMO
Indole is a key environmental cue that is used by many organisms. Based on its biochemistry, we suggest indole is used so universally, and by such different organisms, because it derives from the metabolism of tryptophan, a resource essential for many species yet rare in nature. These properties make it a valuable, environmental cue for resources almost universally important for promoting fitness. We then describe how indole is used to coordinate actions within organisms, to influence the behavior of conspecifics and can even be used to change the behavior of species that belong to other kingdoms. Drawing on the evolutionary framework that has been developed for understanding animal communication, we show how this is diversely achieved by indole acting as a cue, a manipulative signal, and an honest signal, as well as how indole can be used synergistically to amplify information conveyed by other molecules. Clarifying these distinct functions of indole identifies patterns that transcend different kingdoms of organisms.
Assuntos
Bactérias/metabolismo , Eucariotos/metabolismo , Indóis/metabolismo , Comunicação Animal , Animais , Bactérias/genética , Fenômenos Fisiológicos Bacterianos , Evolução Biológica , Eucariotos/genética , Eucariotos/fisiologia , Feminino , Humanos , Masculino , Interações Microbianas , FeromôniosRESUMO
Determining the thermal tolerance of an organism is important when assessing its activity time and survival rate in a given environment. However, thermal tolerance is not a static trait and may be influenced by a number of environmental and organismal factors. We report the results of three experiments investigating the effects of environmental temperature, exposure duration, age, sex, and nutrient availability on the upper thermal tolerance of the adult secondary screwworm, Cochliomyia macellaria. The probability of knockdown and survival was determined using a static method for different environmental temperatures (22, 40, 42, 44, or 45⯰C), exposure durations (1, 2, 4, or 6â¯h), and nutrient availabilities (no food or water, water only, or both food and water) for both sexes and two age classes (youngâ¯=â¯7-9 days post pupal emergence, oldâ¯=â¯10-12 days post pupal emergence). In general, environmental temperature and exposure duration had the greatest effects on both the probability of knockdown and survival. As temperature or duration increased, the probability of knockdown increased while the probability of survival decreased. The availability of nutrients (water only or food and water) increased thermal tolerance at moderate temperatures (42 and 44⯰C), but had no effect at 45⯰C. Female flies were more thermally tolerant than males, regardless of nutrient availability. And age exhibited negligible effects on the probabilities of knockdown or survival, regardless of nutrient availability. These data show multiple environmental factors affected the thermal tolerance of C. macellaria. Thus, such aspects of basic thermal biology should feature more prominently in applied fields using blow flies, including but not limited to forensic entomology, disease ecology, and pollination ecology.
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Dípteros/fisiologia , Termotolerância , Animais , Feminino , Masculino , TemperaturaRESUMO
Generation of insects' biomass from lignocellulose rich organic wastes is of significant challenges in reducing the environmental impact of wastes and in sustaining feed and food security. This research looked at the effects of lignocellulotic exogenous bacteria in the black soldier fly (BSF) organic waste conversion system for biomass production and lignocellulose biodegradation of dairy and chicken manures. Six exogenous bacteria were investigated for cellulolytic activity with carboxymethyl cellulose and found that these tested bacterial strains degrade the cellulose. In this study; a co-conversion process using Hermetia illucens larvae to convert the previously studied best mixing ratio of dairy manure (DM) and chicken manure (CHM) (2:3) and cellulose degrading bacteria was established to enhance the larval biomass production, waste reduction and manure nutrient degradation. BSF larvae assisted by MRO2 (R5) has the best outcome measures: survival rate (99.1%), development time (19.0â¯d), manure reduction rate (48.7%), bioconversion rate (10.8%), food conversion ratio (4.5), efficiency of conversion of ingestion (22.3), cellulose (72.9%), hemicellulose (68.5%), lignin (32.8%), and nutrient utilization (protein, 71.2% and fat, 67.8%). By analyzing the fiber structural changes by scanning electron microscopy and Fourier-transformed infrared spectroscopy (FT-IR), we assume that exogenous bacteria assist the BSF larvae that trigger lead to structural and chemical modification of fibers. We hypothesized that these surface and textural changes are beneficial to the associated gut bacteria, thereby helping to larval growth and reduce waste. The finding of the investigation showed that enhanced conversion of DM and CHM by BSF larvae assisted with lignocellulotic exogenous bacteria could play key role in the manure management.
Assuntos
Simuliidae , Animais , Bactérias , Galinhas , Larva , Esterco , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Antibiotic resistance genes (ARGs) in animal manure are an environmental concern due to naturally occurring bacteria being exposed to these wastes and developing multidrug resistance. The bioconversion of manure with fly larvae is a promising alternative for recycling these wastes while attenuating ARGs. We investigated the impact of black soldier fly (BSF, Hermetia illucens) larval bioconversion of chicken manure on the persistence of associated ARGs. Compared with traditional composting or sterile larval treatments (by 48.4% or 88.7%), non-sterile BSF larval treatments effectively reduced ARGs and integrin genes by 95.0% during 12 days, due to rapid decreases in concentrations of the genes and associated bacteria as they passed through the larval gut and were affected by intestinal microbes. After larval treatments, bacterial community composition differed significantly, with the percentage of Firmicutes possibly carrying ARGs reduced by 65.5% or more. On average, human pathogenic bacteria populations declined by 70.7%-92.9%, effectively mitigating risks of these bacteria carrying ARGs. Environmental pH, nitrogen content and antibiotic concentrations were closely related to both bacterial community composition and targeted gene attenuation in larval systems. Selective pressures of larval gut environments with intestinal microbes, larval bacteriostasis and reformulation of manure due to larval digestion contributed to ARG attenuation.
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Bactérias/metabolismo , Proteínas de Bactérias/genética , Dípteros/metabolismo , Dípteros/microbiologia , Microbioma Gastrointestinal , Esterco/microbiologia , Animais , Antibacterianos/farmacologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Biotransformação , Galinhas , Digestão , Farmacorresistência Bacteriana , Intestinos/microbiologia , Larva/metabolismo , Larva/microbiologia , Esterco/análise , Nitrogênio/metabolismoRESUMO
A chicken manure management process was carried out through co-conversion of Hermetia illucens L. larvae (BSFL) with functional bacteria for producing larvae as feed stuff and organic fertilizer. Thirteen days co-conversion of 1000â¯kg of chicken manure inoculated with one million 6-day-old BSFL and 109â¯CFU Bacillus subtilis BSF-CL produced aging larvae, followed by eleven days of aerobic fermentation inoculated with the decomposing agent to maturity. 93.2â¯kg of fresh larvae were harvested from the B. subtilis BSF-CL-inoculated group, while the control group only harvested 80.4â¯kg of fresh larvae. Chicken manure reduction rate of the B. subtilis BSF-CL-inoculated group was 40.5%, while chicken manure reduction rate of the control group was 35.8%. The weight of BSFL increased by 15.9%, BSFL conversion rate increased by 12.7%, and chicken manure reduction rate increased by 13.4% compared to the control (no B. subtilis BSF-CL). The residue inoculated with decomposing agent had higher maturity (germination index >92%), compared with the no decomposing agent group (germination index â¼86%). The activity patterns of different enzymes further indicated that its production was more mature and stable than that of the no decomposing agent group. Physical and chemical production parameters showed that the residue inoculated with the decomposing agent was more suitable for organic fertilizer than the no decomposing agent group. Both, the co-conversion of chicken manure by BSFL with its synergistic bacteria and the aerobic fermentation with the decomposing agent required only 24 days. The results demonstrate that co-conversion process could shorten the processing time of chicken manure compared to traditional compost process. Gut bacteria could enhance manure conversion and manure reduction. We established efficient manure co-conversion process by black soldier fly and bacteria and harvest high value-added larvae mass and biofertilizer.
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Dípteros , Fertilizantes , Esterco , Proteínas , Animais , Galinhas , LarvaRESUMO
BACKGROUND: With increased availability of de novo assembly algorithms, it is feasible to study entire transcriptomes of non-model organisms. While algorithms are available that are specifically designed for performing transcriptome assembly from high-throughput sequencing data, they are very memory-intensive, limiting their applications to small data sets with few libraries. RESULTS: We develop a transcriptome assembly algorithm that recovers alternatively spliced isoforms and expression levels while utilizing as many RNA-Seq libraries as possible that contain hundreds of gigabases of data. New techniques are developed so that computations can be performed on a computing cluster with moderate amount of physical memory. CONCLUSIONS: Our strategy minimizes memory consumption while simultaneously obtaining comparable or improved accuracy over existing algorithms. It provides support for incremental updates of assemblies when new libraries become available.
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Algoritmos , Perfilação da Expressão Gênica/métodos , Animais , Dípteros/genética , Drosophila melanogaster/genética , Ratos-Toupeira/genética , Splicing de RNA , Análise de Sequência de RNARESUMO
Maggot debridement therapy (MDT) is the use of the larval stage of flies (i.e., Calliphoridae) to remove necrotic tissue and disinfect wounds. Effective MDT requires aseptic technique to prevent the unintentional introduction of pathogenic bacteria into a wound to be debrided; yet the external surface of Calliphoridae eggs is often heavily contaminated with bacteria. Studies of external disinfection of dipteran eggs have been reported, but neither their efficacy nor effect on egg viability has been adequately assessed. The present study evaluated the efficacy of ten disinfection techniques involving immersion, rinse, or a combination of both in formalin, Lysol, formaldehyde, bleach, ethanol, Sporgon, or benzalkonium chloride. All techniques resulted in significant decreases in culturable, aerobic bacterial load on Lucilia cuprina eggs. For L. cuprina, a 10 minute 3% Lysol immersion was the most efficacious, disinfecting 96.67% of egg samples, while resulting in 31.84% egg mortality. The 5% formalin immersion was least efficacious, disinfecting only 3.33% of L. cuprina egg samples, while resulting in 33.51% egg mortality. A formaldehyde immersion, one of the most commonly used disinfection techniques, was moderately effective, disinfecting 66.7% of egg samples, while resulting in 40.16% egg mortality. For Chrysomya rufifacies and Cochliomyia macellaria egg samples, the 10 minute 3% Lysol immersion disinfected 100% of the samples, and for Lucilia sericata, 80% of egg samples, while resulting in 33.97%, 7.34%, and 36.96% egg mortality, respectively. H2 CO disinfected 16.67% of Ch. rufifacies, 26.67% of C. macellaria, and 56.67% of L. sericata egg samples, while resulting in 21.98%, 10.18%, and 32.19% egg mortality, respectively. Due to its high disinfection efficacy and relatively low egg mortality, a 10 minutes 3% Lysol immersion is recommended for sterilizing Calliphoridae eggs prior to rearing of larvae for use in MDT.
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Desbridamento/métodos , Dípteros/microbiologia , Desinfecção , Embrião não Mamífero/microbiologia , Larva/microbiologia , Necrose/terapia , Ferimentos e Lesões/terapia , Análise de Variância , Animais , Cresóis , Desinfecção/métodos , HumanosRESUMO
Understanding the onset and duration of adult blow fly activity is critical to accurately estimating the period of insect activity or minimum postmortem interval (minPMI). Few, if any, reliable techniques have been developed and consequently validated for using adult fly activity to determine a minPMI. In this study, adult blow flies (Diptera: Calliphoridae) of Cochliomyia macellaria and Chrysomya rufifacies were collected from swine carcasses in rural central Texas, USA, during summer 2008 and Phormia regina and Calliphora vicina in the winter during 2009 and 2010. Carcass attendance patterns of blow flies were related to species, sex, and oocyte development. Summer-active flies were found to arrive 4-12 h after initial carcass exposure, with both C. macellaria and C. rufifacies arriving within 2 h of one another. Winter-active flies arrived within 48 h of one another. There was significant difference in degree of oocyte development on each of the first 3 days postmortem. These frequency differences allowed a minPMI to be calculated using a binomial analysis. When validated with seven tests using domestic and feral swine and human remains, the technique correctly estimated time of placement in six trials.
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Dípteros/fisiologia , Comportamento Alimentar/fisiologia , Mudanças Depois da Morte , Animais , Humanos , Oócitos/crescimento & desenvolvimento , Estações do Ano , Suínos , Fatores de TempoRESUMO
Mites are receiving renewed interest in forensic entomology, but the identification of many species associated with carrion and human remains is problematic. We review the taxonomy of the mite species currently known as Myianoetus muscarum (L., 1758) and designate a neotype from the collection of Jean Cooreman in Brussels, Belgium. The species is redescribed based on Cooreman's specimens, specimens previously reported from California and Ontario, Canada, and a large series of new specimens collected from a human corpse in Texas. The species is compared with and distinguished from other species of Myianoetus.
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Ácaros e Carrapatos/anatomia & histologia , Ácaros e Carrapatos/classificação , Animais , Bélgica , Entomologia , Feminino , Ciências Forenses , Humanos , Masculino , TexasRESUMO
During a forensic investigation, the presence of physical marks on human remains can influence the interpretation of events related to the death of an individual. Some tissue injury on human remains can be misinterpreted as ante- or peri-mortem wounds by an investigator when in reality the markings resulted from post-mortem arthropod activity. Unusual entomological data were collected during a study examining the decomposition of a set of human remains in San Marcos, Texas. An adult female Pediodectes haldemani (Girard) (Orthoptera: Tettigoniidae) and an Armadillidium cf. vulgare (Isopoda: Armadilidiidae) were documented feeding on the remains. Both arthropods produced physical marks or artifacts on the remains that could be misinterpreted as attack, abuse, neglect, or torture. Additionally, red imported fire ants, Solenopsis invicta Buren (Hymenoptera: Formicidae), were observed constructing structures in the mark produced by the P. haldemani feeding. These observations provide insight into the potential of post-mortem arthropod damage to human remains, which previously had not been described for these taxa, and therefore, physical artifacts on any remains found in similar circumstances may result from arthropod activity and not ante- or peri-mortem wounds.