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Subject: search.filters.subject.Lucilia cuprina

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    An assessment of the accuracy of morphological techniques for identifying Lucilia cuprina and Lucilia sericata (Diptera: Calliphoridae)
    (Taylor and Francis Group on behalf of the New Zealand Veterinary Association, 2025-10-13) Brett PTJ; Lawrence KE; Kenyon PR; Gedye K; Fermin LM; Pomroy W
    Aims: To assess the accuracy of the morphological identification of Lucilia cuprina and Lucilia sericata by using molecular analysis as a reference standard test, and to describe the seasonality of these species. Methods: A convenience sample of L. cuprina and L. sericata flies was caught on eight farms from across New Zealand and stored at room temperature in 70% alcohol. They were first morphologically identified using published keys and then molecularly identified using primers to amplify the 28S rRNA region of the nuclear genome. The accuracy of the morphological identification was then estimated for each species using the molecular identification as a reference standard test. The correctness of the published keys was also tested by re-examining a sample of misidentified flies using enhanced magnification and photography. Results: The accuracy of the morphological identification for L. cuprina was 0.66 (95% CI = 0.58–0.73) and for L. sericata was 0.7 (95% CI = 0.62–0.77). There was no evidence for a difference in accuracy between species (p = 0.56), and re-examination of the misidentified flies found no faults in the published keys. The study confirmed that L. cuprina has a longer season of activity than L. sericata. Conclusions: These results emphasise the need to use molecular methods to confirm the identification of these species, especially when dealing with large, stored collections, rather than to rely on morphological identification alone. Clinical relevance: Without accurate fly identification and knowledge of insecticide resistance status, effective control and prevention of flystrike in New Zealand could be handicapped.
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    A Field Evaluation of the LuciTrap and the Western Australian Trap with Three Different Baits Types for Monitoring Lucilia cuprina and Lucilia sericata in New Zealand.
    (15/09/2021) Brett P; Lawrence K; Kenyon P; Gedye K; Pomroy W
    Flytraps can be used on farms to monitor the populations of primary strike flies (Lucilia cuprina and Lucilia sericata) and, hence, offer a view regarding the incidence of flystrike on sheep. This study aimed to contrast the specificity and effectiveness of the LuciTrap with its combination of three chemical lures (Lucilures) and the Western Australian Trap with three bait types (LuciLure, Sheep liver with 30% sodium sulphide and squid). A mean model and rate model were fitted to the data. The mean model showed no difference (p > 0.05) in the mean weekly catch for L. cuprina between the Western Australian Trap with LuciLures and the Western Australian Trap baited with sheep liver with 30% sodium sulphide (p < 0.05). Whereas, for L. sericata, no difference (p > 0.05) was found between the Western Australian Trap with LuciLures, the Western Australian Trap baited with sheep liver with 30% sodium sulphide and the LuciTrap. The rate model illustrated that the Western Australian Trap with sheep liver with 30% sodium sulphide and LuciTrap did not differ (p > 0.05) for L. cuprina and L. sericata. Combined, these results indicate that New Zealand farmers can use either the LuciTrap or the Western Australian Trap with sheep liver with 30% sodium sulphide to monitor these target species.
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    Progress towards development of a genetically modified strain of the Australia sheep blowfly Lucilia cuprina suitable for a sterile release program : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Molecular Genetics at Massey University, Palmerston North, New Zealand
    (Massey University, 2002) Li, Xuelei
    The sterile insect technique (SIT) is concerned with the mass-rearing and release of sterilized insects which mate with "wild-type" females in the field, producing no viable offspring. The aim of this study was to use genetic engineering methods to make a strain of the Australia sheep blowfly Lucilia cuprina which is suitable for an area-wide sterile-male release program. The main objectives were: development of an efficient germline transformation system for introducing a target gene into Lucilia and development of an inducible female killing system to produce a male only population. The piggyBac and Minos transposons were evaluated as transformation vectors for L. cuprina. Firstly, Drosophila melanogaster was used as a model system to determine if the frequency of both inter-plasmid transposition and germ-line transformation increases with the level of expression of the piggyBac transposase. Expression of the piggyBac transposase gene was controlled with either the α1-tubulin, hsp83 or hsp70 promoter, which have strong, intermediate and low constitutive activity respectively. The results show that the frequency of piggyBac-mediated germ-line transformation does increase with the level of expression of the transposase. In contrast, there does not appear to be a simple correlation between the level of expression the transposase and the frequency of transposition measured using an inter-plasmid transposition assay. This suggests that this widely used assay may not necessarily predict which is the best "helper" plasmid for germ-line transformation. Secondly, inter-plasmid transposition assays have shown that both piggyBac and Minos transposases are active in blowfly embryos. Thirdly, Drosophila eye color genes and the enhanced green fluorescent protein (EGFP) gene were tested as potential markers for identifying transgenic flies. The most promising marker based on transient expression appears to be EGFP driven by the Drosophila polyubiquitin gene promoter (pUb-EGFP). Fourthly, blowfly embryos were coinjected with the piggyBac helper driven by the D. melanogaster hsp70 promoter and the PUbnlsEGFP marker gene. Two transgenic L. cuprina lines were isolated and characterised by Southern DNA hybridisation analysis and inverse PCR. The transformation frequency was 1.4 to 1.9%. Of the two transformant lines obtained, one had a single copy of the transgene and the other most likely has four copies. This is the first report of germ line transformation of L. cuprina. A tetracycline regulated inducible expression system was adopted to develop a controllable female-killing genetic system based on the D. melanogaster msl2 gene. One component of the system is the tetracycline dependent transactivator (tTA) gene controlled by a constitutive promoter. The other (tetO-msl2) is the msl2 coding region controlled with a promoter bearing seven copies of the tetracycline operator (tetO) sequence. Female D. melanogaster carrying both a promoter-tTA and tetO-msl2 gene constructs would be predicted to die in the absence of tetracycline due to expression of msl2. In this study several promoter-tTA constructs were developed including WH-arm which uses the constitutive armadillo promoter. Drosophila carring both WH-arm and tetO-lacZ transgenes were shown by spectrophotometric and histochemical staining assays to express β-galactosidase but only if raised on media that lacked tetracycline. There was a significant decrease in viability of females carrying both WH-arm and tetO-msl2 gene constructs raised on media lacking tetracycline. However lethality was not 100%. Assembly of the MSL complex on female X chromosomes (due to expression of msl2) was confirmed by immuno staining of polytene chromosomes with anti-MSL3 antibody. Thus it appears that induction of 100% female lethality will require higher levels of msl2 expression than obtained with the WH-arm/tetO-msl2 system for controlling female viability in transgenic Lucilia.