A review of comparative aspects of myiasis in goats and sheep in Europe

Molecular identification of Chrysomya albiceps (Diptera: Calliphoridae) in a case of primary cutaneous myiasis in sheep at southern Brazil

Sheep farming has been growing in Brazil, driven by an expanding consumer market due to greater acceptance of its meat and derivatives. There are several factors that limit sheep production, and one of them is infestation by ectoparasites, which cause stress in animals, weight loss, poor development, low productivity, low quality wool and reduced fertility. Chrysomya albiceps is a species of blowfly belonging to the Calliphoridae family that occurs in neotropical regions, where it causes secondary myiasis. We identified here a rare case of cutaneous myiasis with the presence of tissue lesions caused by C. albiceps in sheep in southern Brazil. We highlight the need to carry out more in-depth studies regarding the biology of these insects, with the aim of proving this atypical behavior for Brazil.

First report on molecular characterization of Oestrus ovis in sheep from India

The objective of the present study is to characterize the dipteran larvae species infesting the sheep being maintained at SRRC, Mannavanur, by means of COI gene based PCR. During the last week of May 2021, post mortem examination of the skull of an Avikalin male sheep (20 months old) revealed the presence of larvae in its nasal sinuses. The larvae were washed in PBS (pH 7.2) and preserved in 70% alcohol. Total genomic DNA was isolated from the larvae using an initial step of grinding with liquid Nitrogen in a sterile mortar and pestle. Using the isolated genomic DNA from the larvae as a template, Cytochrome c oxidase subunit I (COI) gene based PCR was employed using the primers designed based on the COI gene of reference isolate of Oestrus ovis available in the GenBank. Full length COI gene (1534 bp) gene of Oestrus ovis in sheep from South India was targeted in the PCR experiment. The pTZ57R/T vector was used for the cloning of the PCR amplified fragment and the confirmed recombinant plasmid was subjected to sequencing experiments. In addition to morphological examination, based on COI gene based PCR, eventual sequencing experiments and BLAST analysis, it was confirmed that the larvae in the nasal sinuses of sheep from South India were Oestrus ovis. The South Indian isolate of Oestrus ovis is sharing 100% sequence identity both at nucleotide and amino acid levels with that of O. ovis from Spain. The North Indian isolate of O. ovis (from Jammu) exhibited 92% and 99% identity at respective nucleotide and amino acid levels with South Indian isolate. With other members of the subfamily Oestrinae, the share of per cent nucleotide and amino acid identities of South Indian O. ovis ranged from 85-86% to 95-96%, respectively. O. ovis from South India was grouped with the other members of Oestrinae from different geographical areas of the globe in the analysis of phylogenetic tree based on COI amino acid sequences. Based on the research findings, it is concluded that Oestrus ovis is the dipteran species infesting the sheep at Mannavanur, Tamil Nadu, India. To our knowledge, this is the first report on full length nucleotide sequences of COI gene of O. ovis in sheep from Indian subcontinent.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12639-024-01666-2.

Does tail docking prevent Cochliomyia hominivorax myiasis in sheep? A six-year retrospective cohort study

Tail docking is a husbandry practice widely incorporated in sheep farms around the world. It is an irreversible mutilation that impairs animal welfare, both immediately and in the longer term. The defence of tail docking as a practice is centred around the perception that doing so contributes to the promotion of local hygiene, allowing the use of the wool, facilitating reproductive management and reducing the chances of myiasis, a disease caused by the invasion of blowfly larvae in the tissues of warm-blooded animals. However, current understanding of farm animal welfare questions the need to maintain practices such as tail docking. Thus, the aim of this study was to evaluate the effect of tail docking on the incidence of Cochliomyia hominivorax myiasis in sheep in an experimental flock in Brazil during a six-year retrospective cohort study. Relative risk, odds ratio and incidence rate ratio were the association measures adopted. A total of 4,318 data-points were collected and supplied the analytical model. Tail docking did not decrease the risk and, on the contrary, was found to increase the chances of sheep being affected by myiasis. The results support the hypothesis that tail docking is not a protective factor against the occurrence of myiasis and further fuel calls for a rethink of tail docking being deployed as a blanket measure in the prevention of myiasis in sheep.

Efficacy of eprinomectin 5 mg/mL topical solution administered pour on at 1 mg per kg body weight against Oestrus ovis myiasis in sheep and goats

The larvae of the nasal bot, Oestrus ovis, mainly parasitize sheep and goats and some species of wild Caprinae but other mammals and humans are also vulnerable to infestation. Eprinomectin 5 mg/mL topical solution (EPRINEX® Multi, Boehringer Ingelheim) administered at 1 mg eprinomectin per kg body weight pour on was recently authorized as an anthelmintic for sheep and goats with zero hours milk withdrawal in several countries in Europe. As the product in cattle has claims against a broad range of parasites including insect parasites and activity against O. ovis has previously been reported following extra-label use in sheep, its therapeutic efficacy against ovine and caprine O. ovis myiasis was evaluated in three regulatory compliant, masked clinical studies. Pre-study recovery of O. ovis larvae from five or six of six randomly selected animals per study site (Bulgaria, one site, sheep; Greece, two sites, sheep or goats) supported the inclusion of the animals from those sites into the studies. The study animals (34 animals per study) were ranked based on bodyweight and allocated randomly to remain untreated (control) or to be treated with eprinomectin 5 mg/mL topical solution at 1 mL per 5 kg body weight pour on. Treatment efficacy was determined based on O. ovis larval counts of eprinomectin 5 mg/mL topical solution-treated vs. untreated animals three weeks after treatment administration. Live O. ovis larvae, including all three instars in each study, were recovered from 13 or 16 of the 17 control animals in the sheep studies (range, 1 to 14 or 5 to 18 larvae, respectively) and from all 17 controls in the goat study (range, 7 to 18 larvae). In each study, eprinomectin 5 mg/mL topical solution-treated animals had significantly (p < 0.001) fewer live O. ovis larvae than the controls. Efficacy of the treatment was 100% and 91.3% against the combined parasitic O. ovis larval stages in sheep and in goats, respectively. The treatment was well accepted by all animals and no health problems were observed throughout the studies. The results of these studies demonstrated eprinomectin 5 mg/mL topical solution administered pour on at 1 mL per 5 kg body weight to be an efficacious and safe treatment of ovine and caprine oestrosis.

Developmental differences in spatially distinct populations of the forensically relevant blow fly Lucilia sericata - About the comparability of developmental studies (and case work application)

The cosmopolitan blow fly Lucilia sericata is often used in forensic case work for estimating the minimum postmortem interval (PMImin). For this, the age of immature specimens developing on the dead body is calculated by measuring the time taken to reach the sampled developmental stage at a given temperature. To test whether regional developmental data of L. sericata is valid on a global scale, the time taken to reach different developmental stages was compared between a population from Mexico and one from Germany at two different constant temperatures. The German population of L. sericata was collected in Frankfurt/Main, while the Mexican population originated near Oaxaca de Juarez and was transported to Germany in the larval stage. Only the F1 generation was used to avoid adaption of the Mexican flies. Eggs were immediately placed at 20 °C and 30 °C. Five times 30 freshly eclosed larvae per replicate (n = 5) were then transferred to a cup of minced meat in separate containers. The larvae were checked every 8 h for migration, pupariation or emergence of adult flies. The time at which the first individual and 50 % of the specimens per container entered each of these stages, was recorded. Significant differences in the time of development between the two populations were observed at both temperatures. At 20 °C, the first specimens of the Mexican population reached all developmental stages a little (< 1 day to < 2 days) earlier than the German L. sericata. At 30 °C, the Mexican flies also reached the post-feeding stage slightly earlier (0.2 days). However, at 30 °C, the German flies started pupariation significantly earlier (after 5 days) than the Mexican flies (6.9 days) and the adults from Germany also emerged earlier (10.5 days compared to 13.1 days). The same pattern was observed when looking at 50 % of the total number of specimens per container. A comparison with previously published developmental studies was difficult as the experimental design varied widely between studies. However, the results were within the range of most studies. Our study has shown that age estimation can vary widely depending on the population on which the reference data used for the calculations are based. This highlights the importance of using local and population-specific developmental data for estimating the age of blow flies in case work.

Long Time No Hear, Magnificent Wohlfahrtia! Morphological and Molecular Evidence of Almost Forgotten Flesh Fly in Serbia and Western Balkans

The "beautiful viviparous fly", Wohlfahrtia magnifica, may have a magnificent appearance due to its striking morphology; however, it is a potentially deadly agent of obligate traumatic myiasis in humans and animals, with a serious impact on welfare and economics. The fly is found across the Palearctic realm, including the Western Balkan region, with reports from former Yugoslavian countries from the first half of the 20th century. In this paper, a recent case of wohlfahrtiosis recorded in Northern Serbia is evidenced using morphological and molecular techniques. Larvae were collected from two adult sheep with severe hoof myiasis and two young sheep with genital and interdigital myiasis. Morphological identification was performed for adults bred from the infested vulva and third-stage larvae (L3) collected from the hoof wounds, supported with barcoding sequences of the COI gene obtained from larval pairs from the hoof wounds of older and the genitalia of younger sheep. W. magnifica was identified according to the appearance of male fly terminalia and the morphology of L3, which was confirmed after the comparison of representative sequences of the COI gene (deposited in GenBank™ under accession numbers MT027108-MT027114) to those available in GenBank™. This finding represents the first reported case of wohlfahrtiosis in the Western Balkans in 80 years, highlighting the need to re-inform relevant stakeholders to achieve adequate disease control.

Traumatic sheep myiasis: A review of the current understanding

Myiasis, or the infestation of live humans and vertebrate animals by dipterous larvae, is a health issue worldwide. The economic impact and potential threat to animal health and wellbeing of this disease under the animal husbandry sector is considerable. Sheep are a highly vulnerable livestock category exposed to myiasis (sheep strike), due to several unique predisposing factors that attract flies. The successful mitigation of this disease relies on a thorough understanding of fly population dynamics associated with the change in weather patterns and the evaluation of this disease through different branches of science such as chemistry, molecular biology, and microbiology. The present review provides a summary of the existing knowledge of strike in sheep, discussed in relation to the application of volatile organic compounds, metagenomics, and molecular biology, and their use regarding implementing fly control strategies such as traps, and to increase the resilience of sheep to this disease through improving their health and wellbeing.

Genomic insights into evolution and control of Wohlfahrtia magnifica , a widely distributed myiasis‐causing fly of warm‐blooded vertebrates

Wohlfahrtia magnifica is a pest fly species, invading livestock in many European, African and Asian countries, and causing heavy agroeconomic losses. In the life cycle of this obligatory parasite, adult flies infect the host by depositing the first‐stage larvae into body cavities or open wounds. The feeding larvae cause severe (skin) tissue damage and potentially fatal infections if untreated. Despite serious health detriments and agroeconomic concerns, genomic resources for understanding the biology of W. magnifica have so far been lacking. Here, we present a complete genome assembly from a single adult female W. magnifica using a Low‐DNA Input workflow for PacBio HiFi library preparation. The de novo assembled genome is 753.99 Mb in length, with a scaffold N50 of 5.00 Mb, consisting of 16,718 predicted protein‐encoding genes. Comparative genomic analysis revealed that W. magnifica has the closest phylogenetic relationship to Sarcophaga bullata followed by Lucilia cuprina. Evolutionary analysis of gene families showed expansions of 173 gene families in W. magnifica that were enriched for gene ontology (GO) categories related to immunity, insecticide‐resistance mechanisms, heat stress response and cuticle development. In addition, 45 positively selected genes displaying various functions were identified. This new genomic resource contributes to the evolutionary and comparative analysis of dipterous flies and an in‐depth understanding of many aspects of W. magnifica biology. Furthermore, it will facilitate the development of novel tools for controlling W. magnifica infection in livestock.

Traumatic myiasis by Wohlfahrtia magnifica in sheep flocks from southeastern Spain: prevalence and risk factors

Wohlfahrtia magnifica (Diptera: Sarcophagidae) is an obligate myiasis-causing fly of livestock that is widely distributed throughout the Mediterranean basin. A total of 73 683 sheep from 122 flocks in Albacete Province (southeastern [SE] Spain) were examined to detect active traumatic myiasis. The influence of several individual and flock factors on the prevalence was also assessed. The overall flock prevalence of traumatic myiasis was 95.9%, with an individual prevalence of 7.1%. Wohlfahrtia magnifica was identified in all of the positive animals except one that was infested by Lucilia sericata (Diptera: Calliphoridae). Adults of both genders showed a higher risk of infestation than juveniles, whereas males of all ages displayed an increased risk of infestation than females of all ages; the existence of a lambing building on the farm, poor husbandry facilities and the location area were also identified as risk factors. Prevalence was highest in the summer, and the fly season lasted from March to November. Genitalia were the main location of infestation in males (94.4%) and females (76.3%). Our results reveal that traumatic myiasis by W. magnifica is widespread in southeastern Spain, hence preventive measures minimizing the attractiveness of sheep to gravid flies are necessary to avoid health and welfare problems and significant production losses in sheep flocks.

Development of the new microsatellite markers of Lucilia sericata (Diptera: Calliphoridae) from Korea

BACKGROUND

Lucilia sericata is a medical and veterinary important insect species because its larvae feed on tissues of vertebrates including humans. Very few microsatellite makers have been reported from the species to illuminate its genetic variability and population genetic structure.

METHODS AND RESULTS

In this study, L. sericata samples were collected from four different localities in Korea to develop the microsatellite markers to provide basic information on the genetic variability and population genetic structure in Korea of this species. In total, ten new microsatellite markers were sequenced and analyzed. Genetic diversity was performed using these microsatellite markers. The observed heterozygosity varied from 0.205 to 0.824, with an average of 0.546. The expected heterozygosity ranged from 0.579 to 0.886, with an average of 0.804. PIC value varied from 0.553 to 0.876.

CONCLUSIONS

The markers developed in the present study are expected as informative for estimating genetic diversity of L. sericata.

Internal morphological changes during metamorphosis in the sheep nasal bot fly, Oestrus ovis

During the larval stage, oestrid flies (Diptera: Oestridae) are obligate parasites, whereas during the adult stage they are free-living and do not feed. Like other cyclorrhaphous flies, oestrids undergo metamorphosis inside an opaque puparium, formed by the contracted and hardened cuticle of the third-instar larva. The present study documents the internal morphological changes taking place during metamorphosis of the sheep nasal bot fly, Oestrus ovis L., using non-invasive, micro-CT-based virtual histology and provides quantitative data of volumetric changes in specific organs. Virtual histological sections allowed visualisation of the progression and completion of the apolyses, which delimit the different intra-puparial stages, and the connection to the tracheal system of a large gas bubble, which plays an essential role during early metamorphosis. Overall, our results show that the sequence of morphological and volumetric changes in tissues and organs is similar to those found in other cyclorrhaphous flies, but they also reveal developmental differences that result in an adult vestigial digestive tract. Future studies could develop non-invasive, reliable methods for aging the intra-puparial forms of different oestrid species of veterinary importance, based on both qualitative and quantitative markers, thus improving our knowledge of their development and the efficiency of control strategies.

Wolbachia: A tool for livestock ectoparasite control

Ectoparasites and livestock-associated insects are a major concern throughout the world because of their economic and welfare impacts. Effective control is challenging and relies mainly on the use of chemical insecticides and acaricides. Wolbachia, an arthropod and nematode-infecting, maternally-transmitted endosymbiont is currently of widespread interest for use in novel strategies for the control of a range of arthropod-vectored human diseases and plant pests but to date has received only limited consideration for use in the control of diseases of veterinary concern. Here, we review the currently available information on Wolbachia in veterinary ectoparasites and disease vectors, consider the feasibility for use of Wolbachia in the control of livestock pests and diseases and highlight critical issues which need further investigation.

Wohlfahrtiosis in Italy: a case in a puppy and overview of geographical distribution

The report describes a case of urogenital myiasis in a puppy, Canis lupus familiaris (Carnivora: Canidae) caused by Wohlfahrtia magnifica (Diptera: Sarcophagidae) in Calabria, southern Italy. This species is an obligatory agent of myiasis in human and other warm-blooded vertebrates. The puppy was healthy and was not living near farm animals, usual hosts of this flesh fly. An overview of cases of human and animal myiasis caused by W. magnifica in Italy and of data and specimens documented in entomology museum collections is also reported.

The global and regional prevalence of oestrosis in sheep and goats: a systematic review of articles and meta-analysis

Background

Oestrosis, caused by the larvae of Oestrus ovis, commonly known as sheep nose bot, is an obligatory cavitary myiasis of sheep and goats. Oestrus ovis is a widespread parasite, but little is known about the prevalence of oestrosis at the global and broad geographical levels. The present study aimed to explore the epidemiology of oestrosis at the global and regional level to estimate prevalences and their associated factors using a systematic approach. This is, to the author’s knowledge, the first meta-analysis of oestrosis in sheep and goats.

Methods

Published articles were obtained from nine electronic databases (PubMed, CAB Abstracts, Web of Science, Scopus, UCB library, Medline, Biosis Citation Index, Indian journals and Google Scholar) reporting the prevalence of O. ovis in sheep and goats from 1970 to 2018. Pooled prevalences were estimated using a random effect meta-analysis model.

Results

Sixty-six studies were eligible, and data from 40,870 sheep and 18,216 goats were used for quantitative analysis. The random effect estimated prevalence of oestrosis at the global level in sheep was 51.15% (95% CI: 42.80–59.51%) and in goats was 42.19% (95% CI: 33.43–50.95%). The pooled prevalence estimates for Africa, Asia, Europe and the Americas were 47.85% (95% CI: 36.04–59.66%), 44.48% (95% CI: 33.09–55.87%), 56.83% (95% CI: 48.92–64.74%) and 34.46% (95% CI: 19.90–49.01%), respectively. Heterogeneity (I² > 80%) was detected in most pooled estimates.

Conclusions

Oestrosis is highly prevalent in many geographical regions of the world, especially in Europe and Africa. Factors that contribute to the pooled prevalence estimate of oestrosis need to be emphasised in any survey to estimate the true prevalence of oestrosis. Furthermore, there is a need for immunisation or implementation of other preventive measures to reduce the burden of oestrosis in sheep and goats and to improve the health and welfare status.

Electronic supplementary material

The online version of this article (10.1186/s13071-019-3597-2) contains supplementary material, which is available to authorized users.

A formulation of neem and hypericum oily extract for the treatment of the wound myiasis by Wohlfahrtia magnifica in domestic animals

Untreated, traumatic, or wound myiases can cause severe consequences to animal health and welfare as well as economic losses to livestock productions. For healing myiasis-caused wounds, disinfectant such as creolin is wrongly but currently used in association with insecticides. Though effective, creolin is highly toxic to the patients, is inadequate with respect to the repellent effect, and may delay the healing of treated wounds. In this uncontrolled study, the efficacy of the patented plant-derived formulation 1 Primary Wound Dressing© (1-PWD), composed of neem oil (Azadirachta indica A. Juss.) and the oily extract of Hypericum perforatum (L.) flowers, has been investigated. Forty-four domestic animals of different species suffering from wound myiasis lasting for up to 25 days, at different parts of the body, were enrolled in the study. No systemic or local antibiotic or disinfectants' treatment was administered. Larvae recovered on open wounds and adults reared from mature larvae were identified as Wohlfahrtia magnifica. All the treated wounds healed in a range of 10 to 32 days without further infestation. None of the recruited animals presented bacterial complications. Data herein presented indicate that the tested natural plant-derived formulation is able to manage the infestation caused by W. magnifica larvae and the healing process of traumatic infested wounds in several domestic animal species, without any side effect on the living tissue and without the need to use local or systemic chemical or other products.

Oestrus ovis in Ecuador: Importance in the Andean sheep farming

Aim

This study aimed to determine the prevalence of Oestrus ovis in sheep meant for meat commercialization in the main slaughterhouse of the country.

Materials and Methods

Between October 2015 and December 2015, we assessed the occurrence of Oestrus myiasis in the main slaughterhouse localized in Quito. In total, 80 sheep heads were randomly inspected and necropsied. Larvae were removed from nasal cavities and paranasal sinuses and cleaned. ANOVA (generalized linear model) was used to estimate the relationship between sex, age, and place of origin and presence or absence of parasite larvae.

Results

Morphological identification confirmed that 19% (15/80) of the examined animals were positive for Oestrus ovis; from the positive cases, 21% were young animals <12 months old. We found that statistical differences by animal sex, males, were most infested 93% (14/15) than females 7% (1/15). Larvae's L2 were more abundant than other stages (62 of the total 149). 14 of the infested animals were from the Andean places at > 2500 meters above sea level (m.a.s.l.), and only one case from the coastal region at 250 m.a.s.l. with tropical environmental conditions.

Conclusions

Our results showed evidence of the presence of myiasis caused by O. ovis in Andean and coastal places in Ecuador and its adaptation to different environmental conditions from that reported previously in temperate regions from Europe and Africa.

Toxicity and oviposition deterrence of essential oils of Clinopodium nubigenum and Lavandula angustifolia against the myiasis-inducing blowfly Lucilia sericata

Cutaneous myiasis is a severe worldwide medical and veterinary issue. In this trial the essential oil (EO) of the Andean medicinal plant species Clinopodium nubigenum (Kunth) Kuntze was evaluated for its bioactivity against the myiasis-inducing blowfly Lucilia sericata (Meigen) (Diptera Calliphoridae) and compared with that of the well-known medicinal plant species Lavandula angustifolia Mill. The EOs were analysed and tested in laboratory for their oviposition deterrence and toxicity against L. sericata adults. The physiology of EO toxicity was evaluated by enzymatic inhibition tests. The antibacterial and antifungal properties of the EOs were tested as well. At 0.8 μL cm^-2, both EOs completely deterred L. sericata oviposition up to 3 hours. After 24 h, the oviposition deterrence was still 82.7% for L. angustifolia and the 89.5% for C. nubigenum. The two EOs were also toxic to eggs and adults of L. sericata. By contact/fumigation, the EOs, the LC₅₀ values against the eggs were 0.07 and 0.48 μL cm^-2 while, by topical application on the adults, LD₅₀ values were 0.278 and 0.393 μL per individual for C. nubigenum and L. angustifolia EOs, respectively. Inhibition of acetylcholine esterase of L. sericata by EOs (IC₅₀ = 67.450 and 79.495 mg L^-1 for C. nubigenum and L. angustifolia, respectively) suggested that the neural sites are targets of the EO toxicity. Finally, the observed antibacterial and antifungal properties of C. nubigenum and L. angustifolia EOs suggest that they could also help prevent secondary infections.

High innate attractiveness to black targets in the blue blowfly, Calliphora vomitoria (L.) (Diptera: Calliphoridae)

Calliphora vomitoria is a myiasis-causing fly in many animal species including humans. The control of blowflies is still anchored on the use of chemicals. However, mass trapping and lure-and-kill techniques represent a promising alternative to pesticides. Visual and olfactory cues are the main stimuli routing the fly's landing behavior. Notably, color attractiveness has been barely explored in flies of medical and veterinary importance, with special reference to blowflies. In this study, we investigated the innate color preferences in C. vomitoria adults, testing binary combinations of painted targets under laboratory conditions. The identity of tested species C. vomitoria was confirmed by DNA sequencing (18S and cox1 genes). C. vomitoria flies showed a significant preference for black colored targets in all tested binary color combinations, after 5, 15, 30 and 60 min of exposure. Black targets were significantly preferred over blue, red, yellow and white ones. Spectral characteristics of all tested color combinations were quantified and the innate attraction of blowflies towards black targets was discussed in relation to their behavioral ecology. To the best of our knowledge, this is the first report on innate color preferences in the Calliphora genus. Our findings can be useful to develop new, cheap and reliable monitoring traps as well as "lure and kill" tools to control blowfly pests.

Risk factors for cutaneous myiasis (blowfly strike) in pet rabbits in Great Britain based on text-mining veterinary electronic health records

Blowfly strike is a devastating and often rapidly fatal disease in rabbits. In Great Britain (GB), Lucilia sericata is the primary causative species. Despite its severity, there has been minimal investigatory work into the disease in rabbits. Here we used text mining to screen electronic health records (EHRs) from a large sentinel network of 389 veterinary practices in GB between March 2014 and April 2017 for confirmed cases of blowfly strike in rabbits. Blowfly strike was identified in 243 of 42,226 rabbit consultations (0.6%), affecting 205 individual rabbits. The anatomical site of recorded blowfly strike lesions was overwhelmingly the perineal area (n = 109, 52.4%). Less commonly lesions were observed affecting other areas of the body (n = 9, 4.3%) and head (n = 8, 3.8%); in 83 consultations (39.9%), the affected area was not specified. Of the rabbits presenting with blowfly strike, 44.7% were recorded as being euthanized or died. A case control study was used to identify risk factors for blowfly strike in this population. Whilst sex and neuter status in isolation were not significantly associated with blowfly strike, entire female rabbits showed a 3.3 times greater odds of being a case than neutered female rabbits. Rabbits five years of age and over were more than 3.8 times likely to present for blowfly strike. For every 1 °C rise in environmental temperature between 4.67 °C and 17.68 °C, there was a 33% increase risk of blowfly strike, with cases peaking in July or August. Overall blowfly strike cases started earlier and peaked higher in the south of Great Britain. The most northerly latitude studied was at lower risk of blowfly strike than the most southerly (OR = 0.50, p < 0.001). There appeared to be no significant relationship between blowfly strike in rabbits and either the sheep density or rural and urban land coverage types. The results presented here can be used for targeted health messaging to reduce the impact of this deadly disease for rabbits. We propose that real-time temporal and spatial surveillance of the rabbit disease may also help inform sheep control, where the seasonal profile is very similar, and where routine surveillance data is also not available. Our results highlight the value of sentinel databases based on EHRs for research and surveillance.

First record of Phormia regina (Meigen, 1826) (Diptera: Calliphoridae) from mummies at the Sant'Antonio Abate Cathedral of Castelsardo, Sardinia, Italy

The studies of insects from archaeological contexts can provide an important supplement of information to reconstruct past events, climate and environments. Furthermore, the list of the species present in an area in the past allows the reconstruction of the entomofauna on that area at that time, that can be different from the nowadays condition, providing information about biodiversity changes. In this work, the results of a funerary archaeoentomological study on samples collected from mummified corpses discovered during the restoration of the crypt of the Sant’Antonio Abate Cathedral of Castelsardo (Sardinia, Italy) are reported. The majority of the sampled specimens were Diptera puparia, whereas only few Lepidoptera cocoons and some Coleoptera fragments were isolated. Among Diptera, Calliphoridae puparia were identified as Phormia regina (Meigen, 1826) and Calliphora vicina, (Robineau-Desvoidy, 1830) both species typical of the first colonization waves of exposed bodies. Three puparia fragments were also identified as belonging to a Sarcophaga Meigen, 1826, species (Sarcophagidae). Several Muscidae puparia of the species Hydrotaea capensis (Weidmermann, 1818), a late colonizer of bodies, and typical of buried bodies were also collected. The few moth (Lepidoptera) cocoons were identified as belonging to the family Tineidae. This family comprises species feeding on dry tissues and hair typical of the later phases of the human decomposition. Among Coleoptera a single specimen in the family Histeridae, Saprinus semistriatus (Scriba, 1790) and a single elytra, potentially of a species in the family Tenebrionidae, were also collected. Overall, the samples collected indicated an initial colonization of the bodies in an exposed context, mainly in a warm season. This research allows the finding of elements indicating the presence, at least in the past, of P. regina in Sardinia. This species at the moment seems extinct from Sardinia while it is quite common in the continent.

Oestrus ovis L. (Diptera: Oestridae) Induced Nasal Myiasis in a Dog from Northern Italy

A companion dog from Milan province (northern Italy), presenting with frequent and violent sneezing, underwent rhinoscopy, laryngoscopy, and tracheoscopy procedures. During rhinoscopy, a dipteran larva was isolated from the dog and identified as first instar larval stage of O. ovis by morphological features. Reports of O. ovis in domestic carnivores are sporadic and nevertheless this infestion should be considered as a possible differential diagnosis of rhinitis in domestic carnivores living in contaminated areas by the fly as consequence of the presence of sheep and goats. This report described a case of autochthonous infestion in a dog from an area where O. ovis was not historically present but it could be affected by a possible expansion of the fly as a consequence of climate change. This is the first record of Oestrus ovis infestion in a dog in Italy and, at the same time, the most northerly finding of larvae of sheep bot fly in the country.

An acetone extract of Clausena anisata may be a potential control agent for flies encountered in cutaneous myiasis

Clausena anisata is a medicinal plant used traditionally to treat myiasis and as an insect repellent by various communities. We have previously demonstrated the effects of C. anisata extracts on blowfly feeding and development in our laboratory. The impact of C. anisata leaf extracts on populations of different fly species on farms in Mpumalanga, South Africa was investigated in this study under field conditions. Flies were exposed to liver baits treated with acetone leaf extracts of C. anisata (150 mg/mL). Fly numbers and composition on two farms, with and without C. anisata treated liver, were compared during a period of 12 weeks when fly populations were expected to be high. Observations were made on fly behaviour and development, adult sizes and numbers. The flies exposed to liver treated with the leaf extract of C. anisata had a decreased rate of development, prolonged larval period, smaller body sizes and more sluggish behaviour compared to those subjected to the control treatment. No significant differences were, however, found between the numbers and sizes of flies on the treated and on the control farm, which was most likely due to the limited nature of the baiting programme we followed. The effects of C. anisata extracts on blowfly behaviour and development observed in previous laboratory studies were confirmed in this field evaluation. Although the extracts did not have a significant effect on the overall population size in this experiment, we believe that the C. anisata leaf extract could be useful in integrated pest management based on its effect on larval development. In addition, species such as Lucilia cuprina and Chrysomya marginalis seemed to have been repelled by the C. anisata treated liver; as a result, further work should explore this aspect and how it can be used for the protection of animals.

Traumatic Myiasis: A Neglected Disease in a Changing World

Traumatic myiasis, the parasitic infestation by fly larvae in traumatic lesions of the tissues of living vertebrates, is a serious medical condition in humans and a welfare and economic issue in domestic animals. New molecular studies are providing insights into its evolution and epidemiology. Nevertheless, its incidence in humans is generally underreported, particularly in tropical and subtropical regions. Myiasis in domestic animals has been studied more extensively, but continuous management is difficult and expensive. A key concern is the inadvertent introduction and global spread of agents of myiasis into nonendemic areas, facilitated by climate change and global transport. The incursion of the New World screwworm fly (Cochliomyia hominivorax) into Libya is the most notable of many such range shifts and demonstrates the potential risks of these parasites and the costs of removing them once established in a geographic area. Nevertheless, the insect agents of myiasis can be of societal benefit to forensic science and in medicine as an aid to wound treatment (larval therapy).

Ectoparasites of goats in the UK

The goat industry in the UK has expanded rapidly in recent years, but at present there is only a poor understanding of the prevalence of parasitic diseases in this farming system. Here, a questionnaire survey of 110 goat owners was used to address this issue. Problems with louse infestation in the previous 12 months were reported by 23% of owners and 19% reported mange. Chorioptic mange was the most common form, with 14 of 21 cases. Sarcoptic mage accounted for only 3 cases and demodex and psoroptic mange each made up 2 cases. Only 53 farmers (48%) said that they took preventative measures to protect their animals against ectoparasite infestation; 20 of these relied on macrocyclic lactones (MLs), the most common product specified was ivermectin. Therapeutic treatment was used by all respondents who said that they had experienced ectoparasites, and again ivermectin was the most common treatment. The use of fipronil was specified by 3 respondents, including one commercial meat producer. Four farmers said that they used antibiotics as an ectoparasiticide. This pattern of treatment for ectoparasites, with reliance on MLs, has implications for the inadvertent selection of resistance in endoparasites. The results suggest that ectoparasites are a major problem for many goat owners, both commercial and non-commercial, but that there is a need for better information for the goat producing community about the optimum approaches to parasite prevention and treatment.

Traumatic myiasis agents in Iran with introducing of new dominant species, Wohlfahrtia magnifica (Diptera: Sarcophagidae)

OBJECTIVE

To study agents of animal wound myiasis in various geographical districts of Fars province.

METHODS

This study has been done in Fars province, located in the southern part of Iran. Sums of 10 358 domestic animals have been visited from April 2011 to March 2012. The infected wounds in any parts of animal body were sampled by means of forceps.

RESULTS

About 61% of all animal wound myiasis were caused by larvae of Wohlfahrtia magnifica. The most wound myiasis cases due to this species occurred in central part of Fars province. There wasn't any significant difference between sheep and goat in infestation with myiasis (P>0.05). The infestation rate of myiasis in cattle community was 0.86%.

CONCLUSIONS

The infestation rate of livestock was lower than other works in Iran and some other countries like Saudi Arabia. Chrysomya bezziana has been mentioned as main myiasis agent in Iran. But in this study it cleared that similarly to some European countries, the common animal myiasis agent in Iran is Wohlfahrtia magnifica. Introducing new species as principal agent for myiasis can help public health and animal husbandry policy makers to prepare sufficient and effective control and/or preventive measures for this disease.

Isolation of seselin from Clausena anisata (Rutaceae) leaves and its effects on the feeding and development of Lucilia cuprina larvae may explain its use in ethnoveterinary medicine

ETHNOPHARMACOLOGICAL RELEVANCE

The leaves of Clausena anisata are used traditionally to expel maggots from wounds of animals in Zimbabwe. We have previously proved in the laboratory that the plant certainly affects the behaviour and growth of blowfly larvae. The objective of this study was to isolate and identify the active compounds responsible for this activity.

MATERIALS AND METHODS

The acetone extract of Clausena anisata leaf powder was separated by solvent-solvent partition into five fractions. The n-hexane fraction was the most active in the larvicidal assay and therefore subjected to open column chromatography on silica gel.

RESULTS

The isolated compound was identified by nuclear magnetic resonance (NMR) and mass spectroscopy (MS) as the pyranocoumarin, seselin, chemically known as 2',2'-dimethylpyranocoumarin. It inhibited feed intake in the first and second instars of blowfly larvae at the minimum concentration tested of 1 ppm resulting in significant lower mass pupae (13.5±0.5 mg and 22.4±0.4 mg for the first and second instar larvae respectively) compared to the solvent control group (26.19±0.8 mg) (p<0.05).

CONCLUSIONS

This is the first report of the isolation of seselin from the leaves of Clausena anisata and the first report of the compound having an effect against blowfly larvae.

Extracts of four plant species used traditionally to treat myiasis influence pupation rate, pupal mass and adult blowfly emergence of Lucilia cuprina and Chrysomya marginalis (Diptera: Calliphoridae)

ETHNOPHARMACOLOGICAL RELEVANCE

Aloe zebrina, Clausena anisata, Erythrina lysistemon and Spirostachys africana are used traditionally in southern Africa to combat and/or treat myiasis, the infestation of the skin of mammals by larvae of a variety of fly species belonging to the arthropod order Diptera.The objective of the study was to establish the in vitro effect of extracts of these plant species on blowfly larvae to ascertain the potential use of these extracts and validate the traditional use.

MATERIALS AND METHODS

Chrysomya marginalis and Lucilia cuprina larvae cultured in the laboratory under controlled conditions were exposed to meat treated with acetone and aqueous extracts of four different plant species. In addition to solvent controls, the effects of the plant extracts were tested at concentrations of 10, 25, 50, 75, 100 and 150 mg/ml. Larval behaviour, larval development and emergence of adult flies were assessed after exposing the larvae to the treated meat. Ivermectin was used as a positive control while acetone and water served as solvent controls. Cytotoxicity of the extracts was determined using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide] assay against C3A human liver cells, bovine dermis cells and Vero African green monkey kidney cells.

RESULTS

An increase in the concentration of the acetone plant extracts resulted in a decrease in the ingestion of meat by larvae, pupal mass and adult emergence rates. The R(2) values for the correlation between dose and pupal mass was 0.92, 0.74 and 0.65 for A. zebrina, C. anisata, and E. lysistemon respectively. For C. anisata and S. africana extracts the increase in the concentration was also associated with the emerging adult flies being smaller. C. anisata was the most toxic plant extract, with an average IC(50) of 39 μg/ml, while E. lysistemon was the least toxic. Vero cells were the most susceptible cell type, with an average IC(50) of less than 100 μg/ml, while the human liver cells were the most resistant to the effect of the plant extracts.

CONCLUSIONS

The results suggest that the plants may contain compounds that interfere with larval feeding and the neuroendocrine control mechanisms in the blowfly. It appears that some of these plant species have the potential to deliver a product that can be used to control myiasis.