Showing papers on "Lucilia cuprina published in 2014"

Insect Colonization and Succession on Rabbit Carcasses in Southwestern Mountains of the Kingdom of Saudi Arabia.

Abstract: This study describes for the first time the necrophagous insects attracted to carcasses of the European rabbit in the mountains of Al-Baha Province of southwestern Kingdom of Saudi Arabia (KSA). Twenty-four rabbit carcasses were exposed in 2010 during spring (March, April, and May), summer (June, July, and August), and autumn (September, October, and November). The calliphorid fly species, Calliphora vicina Robineau-Desvoidy, Chrysomya marginalis (Wiedemann), Chrysomya chloropyga (Wiedemann), Chrysomya albiceps (Wiedemann), and Lucilia cuprina (Wiedemann), the sarcophagid Liosarcophaga babiyari (Lehrer), and muscoid flies Musca domestica (L.) and Musca stabulans Fallen were attracted to the carcasses. Seven species of Coleoptera, the dermestid Dermestes maculatus (De Geer), three species of hister beetles, Saprinus moyses Marseul, Saprinus ruber gemminigeri, and Saprinus chalcites (Illiger), the tenebrionid Himatismus sp., the clerid species, Necrobia ruficollis (F.), and the staphylinid beetle Creophilous maxillosus (L.) were also attracted to the rabbit carcasses. One species of adult pteromalid fly pupal parasitoid Nasonia sp. was also collected. The dominant larvae on all the rabbit carcasses were Ch. albiceps, L. cuprina, and Li. babiyari. Insect activity caused rabbit carcasses to decompose faster during summer (21.38 ± 0.49 d) compared with spring (27.5 ± 0.73 d) and autumn (30.38 ± 0.50 d). This study indicates that in this region of KSA, Ch. albiceps, L. cuprina, and Li. babiyari are species useful for estimating minimal postmortem intervals.

Morphological identification of Lucilia sericata, Lucilia cuprina and their hybrids (Diptera, Calliphoridae).

Abstract: Hybrids of Lucilia sericata and Lucilia cuprina have been shown to exist in previous studies using molecular methods, but no study has shown explicitly that these hybrids can be identified morphologically. Published morphological characters used to identify L. sericata and L. cuprina were reviewed, and then scored and tested using specimens of both species and known hybrids. Ordination by multi-dimensional scaling indicated that the species were separable, and that hybrids resembled L. cuprina, whatever their origin. Discriminant function analysis of the characters successfully separated the specimens into three unambiguous groups - L. sericata, L. cuprina and hybrids. The hybrids were morphologically similar irrespective of whether they were from an ancient introgressed lineage or more modern. This is the first evidence that hybrids of these two species can be identified from their morphology. The usefulness of the morphological characters is also discussed and photographs of several characters are included to facilitate their assessment.

Predicting the geographic distribution of Lucilia sericata and Lucilia cuprina (Diptera: Calliphoridae) in South Africa

Abstract: Lucilia sericata (Meigen, 1826) and Lucilia cuprina (Wiedemann, 1830) (Diptera: Calliphoridae: Luciliinae) have medical, veterinary and forensic importance. Knowing their distribution in South Africa would allow more effective management and utilisation of these flies. Their predicted geographic distributions in South Africa were modelled using maximum entropy analysis of selected climatic variables. The most important environmental variables in modelling the distributions were the magnitude of monthly rainfall and the magnitude of the monthly maximum temperature for L. sericata and the seasonal variation in monthly mean humidity and magnitude of monthly rainfall for L. cuprina. A clear geographical bias was shown in museum records and supports the need for focused surveys. There was no correlation between the predicted distribution of L. cuprina and sheep farming in South Africa, nor between the predicted distribution of L. sericata and human population density. Although their patterns of occurrence differed, both species are widely distributed in South Africa and therefore one cannot identify these flies by locality alone — morphological or molecular identification is necessary.

Sex determination mechanisms in the Calliphoridae (blow flies).

Abstract: The Calliphoridae or blow flies are a family of insects that occupy diverse habitats and perform important ecological roles, particularly the decomposition of animal remains. Some Calliphoridae species are also important in the forensic sciences, in agriculture (e.g. as livestock pests) and in medicine (e.g. maggot therapy). Calliphoridae provide striking examples in support of the hypothesis that sex determination regulatory gene hierarchies evolve in the reverse order, with the gene at the top being the most recently added. Unlike the model fly Drosophila melanogaster, where sex is determined by the number of X chromosomes, in the Australian sheep blow fly (Lucilia cuprina) sex is determined by a Y-linked male-determining gene (M). A different regulatory system appears to operate in the hairy maggot blow fly (Chrysomya rufifacies) where the maternal genotype determines sex. It is hypothesized that females heterozygous for a dominant female-determining factor (F/f) produce only female offspring and homozygous f/f females produce only sons. The bottom of the regulatory hierarchy appears to be the same in D. melanogaster and L. cuprina, with sex-specific splicing of doublesex transcripts being controlled by the female-specific Transformer (TRA) protein. We discuss a model that has been proposed for how tra transcripts are sex-specifically spliced in calliphorids, which is very different from D. melanogaster.

Development and evaluation of male-only strains of the Australian sheep blowfly, Lucilia cuprina

Abstract: The Australian sheep blowfly Lucilia cuprina (Wiedemann) is a major pest of sheep in Australia and New Zealand. From the 1960s to the 1980s there was a major effort to develop "field female killing" or FFK strains of L. cuprina that could be used for a cost-effective genetic control program. The FFK strains carried eye color mutations that were lethal to females in the field but not under conditions in the mass rearing facility. Males did not die in the field as normal copies of the eye color genes had been translocated to the Y chromosome and an autosome. Although the FFK strains showed some promise in field tests, a genetic control program in mainland Australia was never implemented for several reasons including instability of the FFK strains during mass rearing. A stable transgenic strain of L. cuprina that carried one or more dominant repressible female lethal genes offered the potential for efficient genetic control of blowfly populations. Here I review our research on tetracycline-repressible female lethal genetic systems, Lucilia germ-line transformation and sex determination genes that ultimately led to the successful development of transgenic "male-only" strains of L. cuprina. The technology developed for L. cuprina should be directly transferable to other blowfly livestock pests including L. sericata and the New World and Old World screwworm. 29

Cloning, recombinant expression and inhibitor profiles of dihydrofolate reductase from the Australian sheep blow fly, Lucilia cuprina

Abstract: While dihydrofolate reductase (DHFR) is an important drug target in mammals, bacteria and protozoa, no inhibitors of this enzyme have been developed as commercial insecticides. We therefore examined the potential of this enzyme as a drug target in an important ectoparasite of livestock, the Australian sheep blow fly, Lucilia cuprina (Diptera: Calliphoridae) (Wiedemann). The non-specific DHFR inhibitors aminopterin and methotrexate significantly inhibited the growth of L. cuprina larvae, with IC50 values at µg levels. Trimethoprim and pyrimethamine were 5-30-fold less active. Relative IC50 values for the inhibition of recombinant L. cuprina DHFR by various inhibitors were in accordance with their relative effects on larval growth. The active-site amino acid residues of L. cuprina DHFR differed by between 34% and 50% when compared with two mammalian species, as well as two bacteria and two protozoa. There were significant charge and size differences in specific residues between the blow fly and human DHFR enzymes, notably the L. cuprina Asn21, Lys31 and Lys63 residues. This study provides bioassay evidence to highlight the potential of blow fly DHFR as an insecticide target, and describes differences in active site residues between blow flies and other organisms which could be exploited in the design of blow fly control chemicals.

Effective control of a suspected cyromazine‐resistant strain of Lucilia cuprina using commercial spray‐on formulations of cyromazine or dicyclanil

Abstract: Objective To demonstrate the protection of Merino sheep from flystrike by Lucilia cuprina with cyromazine or dicyclanil in an implant study and in the field. Methods In the implant study, sheep were treated with cyromazine or dicyclanil and implanted with 1st-stage larvae from a newly isolated field strain of L. cuprina (CYR-LS) or a reference strain (DZR50), then assessed over 3 days and compared with the implants on untreated control sheep. In the field study, weaner lambs were treated with cyromazine or dicyclanil and monitored weekly for flystrike over 18 weeks of grazing on the same farm from which the L. cuprina were isolated. Results Implant study: cyromazine (6%) provided effective protection against CYR-LS and DZR50 L. cuprina for a minimum of 13 and 10 weeks, respectively. Dicyclanil (5%) provided at least 18 weeks' protection against both strains. Field study: only 1 of 386 lambs in the cyromazine-treated group was struck in the first 14 weeks of the trial. No strikes occurred in the 198 sheep treated with dicyclanil (5%). Rainfall, temperature and flytrap data indicated consistent fly pressure during the study. Conclusions Based on the results of these studies, there was no evidence of reduced susceptibility to cyromazine or dicyclanil and the periods of protection of sheep against L. cuprina were unaffected and consistent with the registered label claims.

An initial study of insect succession on decomposing rabbit carrions in Harare,Zimbabwe

Abstract: Objective:To investigate insects visiting sun exposed and shaded decomposing rabbit carcasses and to establish the relationship between insects and carcasses which may be of forensic importance in Harare.Methods:Two rabbits weighing 2.3 kg and 2.5 kg were killed by sharp blows on the head.One was exposed to the sun while the other was placed under shade.The carcasses were allowed to decompose and insects were collected twice a day for the first week and thereafter once a day up to the end of the 7 weeks.Maggots were also collected from the decomposing carcasses and reared.Results:Five dipteran families(Galliphoridae,Muscidae,Sarcophagidae,Phoridae and Drosophilidae)were identified from the sun-exposed carcass.Species collected included Lucilia cuprina(L.cuprina),Chrysomya albiceps(C.albiceps),Musca domestica,Sarcophaga sp.and Drosophila sp.Four families(Calliphoridae,Muscidae,Phoridae,Anthomyiidae)were identified from the shaded carcass.Representatives of these families included L cuprina,C.albiceps,Musca domestica,and Hydrotaea sp.Three Coleopteran families(Histeridae,Cleridae and Dermestidae)were identified from hodt carcasses.The observed species were Saprinus sp,Necrobia rufipes and Dermestes sp.Fomicidae(Hymenoptera)was represented by only one species(Pheidoie sp.)Flies which emerged from the rearing units were L cuprina,Lucilia sp.,C.albiceps,Sarcophaga sp.and Sepsis sp.).Conclusions:Of the dipteran species collected during the study,L cuprina and C.albiceps could be important for further forensic studies since they were collected from the carcasses and also observed from the rearing units.

Age-Dependent Gene Expression of Blow Fly Lucilia cuprina (Diptera: Calliphoridae) during Egg Development Improving Age Estimation in Forensic Entomology

Abstract: Estimating the age of immature stages of necrophagous flies developing on corps, may provide clues for understanding the minimum post-mortem intervals (PMI) to aid death investigation. It can be hard to comprehend precisely the interval age of developmental stage that does not increase in size including egg. In this study we investigated the feasibility of predicting egg age from ovi-position to hatching over 2 hour’s intervals of egg development. The expression profile of three genes, cuticle I, Ecdysone receptor (EcR) and chymotrypsin of lucilia cuprina (Diptera: Calliphoridae) were determined at 2, 6, and 8 hours of egg development. Semi-quantitative reverse transcriptase (RT)-PCR were applied for profiling of indicated genes expressions from eggs of different developmental stages by designing specific primers sets. Target transcripts were then quantified from the gel using image J and syn gene programs. The results indicated time-dependent expressions of the three genes with significant increase at the selected time points. Cuticle 1 expression was increased up to 2, 25 and 6 folds at 4, 6 and 8 hours respectively when compared to 2 hours expression level. Likewise a significant induction of both chymotrypsin and EcR (around 1.2, 1.7 then 1.2 and 3, 2, 6 folds, respectively) during 4, 6 and 8 hours were observed. Collectively our results indicate that developmental eggs exhibit differential and specific time-dependent expression profile of target genes that can contribute as measurable factors in future investigations.

Effects of sodium chloride on oviposition and development of blowfly, Lucilia cuprina, (Wiedmann) (Diptera : Calliphoridae)

Abstract: Effects of five different concentrations of sodium chloride (5 to 25%) treated fish flesh was tested on oviposition, growth and developmental parameters of blowfly, Lucilia cuprina (Wiedemann). The salt worked as an oviposition deterrent in the female flies. The highest amount of eggs (0.247 ± 0.0464 g) was oviposited on lowest salt concentration (5%) and the minimum amount (0.0003 ± 0.0004 g) of eggs was laid on the highest salt concentration (25%). The eggs laid on 20 and 25% salt treated fishes were not hatched. The larval periods were significantly affected by 10 and 15% salt treated fish while the pupal periods were prolonged at 15% of salt treated fish (p < 0.05). Average larval and pupal durations in control were 4.543 ± 0.18 and 4.833 ± 0.753 days, respectively, whereas at 15% salt average larval and pupal durations were 5.937 ± 0.133 and 5.5 ± 0.548 days, respectively. The average weight of the larvae and pupae were also reduced with the high concentrations of salt. Pupation rate also significantly reduced at higher concentrations of salt. These results suggest that application of 15% salt in raw fish can effectively protect sun‐drying fish from blowfly infestation. DOI: http://dx.doi.org/10.3329/dujbs.v23i1.19825 Dhaka Univ. J. Biol. Sci. 23 (1): 47-51, 2014