Nasal bots...a fascinating world!

Dissecting the Effects of Cephenemyia stimulator on the Olfactory Turbinates and Nasopharynx of Roe Deers (Capreolus capreolus)

Nasopharyngeal myiasis in European roe deer (Capreolus capreolus) is a pathological condition caused by the larval stages of Cephenemyia stimulator, a fly from the Oestridae family. These larvae reside in the host's upper respiratory tract for months, inducing significant tissue damage and clinical symptoms. The lifecycle of Cephenemyia stimulator is complex, involving three larval stages before maturation into adult flies, with each stage contributing to the progressive pathology observed in the host. Despite their prevalence, the histopathological effects of these larvae in the nasal and nasopharyngeal cavities have been understudied. Our study fills this knowledge gap by providing a detailed histopathological analysis of the affected tissues, using various staining techniques to reveal the extent and nature of the damage caused by these parasitic larvae. This histopathological examination reveals significant alterations within the nasopharyngeal mucosa and nasal cavity, including erythematous changes, mucosal metaplasia, fibrosis, and tissue necrosis. Parasitic cysts and eosinophilic infiltration further characterize the impact of the infestation, compromising not only the mucosal integrity but also potentially the olfactory function of the affected animals. This research is crucial for understanding the impact of myiasis on both the health and olfactory capabilities of roe deer populations and could have significant implications for wildlife management and conservation.

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.

Cyclospora cayetanensis: A Perspective (2020-2023) with Emphasis on Epidemiology and Detection Methods

Cyclospora cayetanensis infections are prevalent worldwide, and the parasite has become a major public health and food safety concern. Although important efforts have been dedicated to advance toward preventing and reducing incidences of cyclosporiasis, there are still several knowledge gaps that hamper the implementation of effective measures to prevent the contamination of produce and water with Cyclospora oocysts. Some of these data gaps can be attributed to the fact that access to oocysts is a limiting factor in C. cayetanensis research. There are no animal models or in vivo or in vitro culture systems to propagate the oocysts needed to facilitate C. cayetanensis research. Thus, researchers must rely upon limited supplies of oocysts obtained from naturally infected human patients considerably restricting what can be learnt about this parasite. Despite the limited supply of C. cayetanensis oocysts, several important advances have happened in the past 3 years. Great progress has been made in the Cyclospora field in the areas of molecular characterization of strains and species, generation of genomes, and development of novel detection methods. This comprehensive perspective summarizes research published from 2020 to 2023 and evaluates what we have learnt and identifies those aspects in which further research is needed.

Nasopharyngeal myiasis due to Cephalopina titillator in Southeastern Iran: a prevalence, histopathological, and molecular assessment

The Cephalopina titillator is one of the most important causative agents of nasal myiasis in camels. This study aimed to explore the prevalence, histopathological effects, and molecular identification of C. titillator infestation in camels of Kerman province, South-Eastern Iran, between 2019 and 2021. The larvae were placed in 10% formalin for histopathological evaluation and species identification. Pieces of larval abdominal segments of C. titillator were selected for extraction of DNA. Partial mitochondrial CO1 genes were sequenced for final analysis. Out of the 870 camels examined, 339 (38.9%) were infested with larval stages of C. titillator. There was a significant difference between age and infection rate (P = 0.001), while no association between males and females (P = 0.074) was found. The infection rate was significantly higher in the winter (P < 0.001) than in the other seasons. In this study, different lesions depending on duration, locations, and the depth of larval adhesion notably degeneration changes, necrosis, and ulceration were observed. Also, in chronic cases, granulation tissue reactions were organized. Cephalopina titillator was confirmed by PCR sequencing analysis using mitochondrial CO1 region. A 582 bp nucleotide sequence was deposited in GenBank under the MW136151 accession number. Phylogenetic analysis of CO1 produced a single uniform sister clade to MZ209004 and MW167083 records from China and Iraq, respectively. The high prevalence of C. titillator in camels in this region and other areas of Iran declares that the country is in an endemic status and displays the existence of the potential risk for camels.

Prevalence of Oestrus ovis in small ruminants from the eastern Iberian Peninsula. A long-term study

Oestrus ovis is an obligate parasite that causes myiasis in domestic ruminants, being commonly found in the Mediterranean area. From 2009 to 2019 a total of 3476 heads of culling sheep and goats from the Mediterranean coast of Spain were examined for the presence of O. ovis. The total prevalence was 56.3%, significantly higher in sheep than in goats (61.2% and 43%, respectively). Differences were found in the mean annual prevalence, with the highest value being registered in 2018 (61.7%) and the lowest in 2012 (50.3%). Autumn, for sheep, and winter, for goats, were the seasons with the highest number of infested specimens. Temperature, but not rainfall, was found to be associated with prevalence (p < 0.05). Most L1 were found in the anatomic region I (septum, meatus, and ventral conchae), while L2 and L3 were mainly located in regions II (nasopharynx, ethmoid labyrinth, and dorsal conchae), and III (sinuses). The overall intensity was 12.8 larvae per head, significantly higher in sheep (13.3) than in goats (3.5). Our results confirm the high prevalence of O. ovis in sheep and goats in this geographic area over the last decade, with the trend increasing in recent years in association with higher mean temperatures.

First Study of Pharingomyia picta and Cephanemyia auribarbis in Wild Populations of Red Deer (Cervus elaphus) in Portugal

Simple Summary

This study aimed to provide the first epidemiological data on nasopharyngeal myiasis in wild red deer from Portuguese territory. This parasitosis consists of the infestation of the host nasopharynx by Diptera larvae. In this study, the first scientific report in Portugal, a high level of prevalence (50.6%) and mean intensity of parasitism (11.38 larvae) were found. The following two larvae species were identified: Pharyngomyia picta and Cephenemyia auribarbis. The life cycle of this species can be summarised in the following series of stages: one adult stage, three larval stages, and one pupa stage. The larvae are the parasitic form, living and growing inside the host. With their spicules and hooks, they progress into the host’s nasal cavities causing sinusitis, sneezing, purulent mucous exudates, dyspnea, and swallowing. In addition, they can also cause neurologic symptomatology derived from erratic larvae migrations. Therefore, it would be important to develop further studies to estimate the sublethal effect of this parasitosis, for example, investigate whether it interferes with the roar and the reproductive performance, or if it leads to losses in carcass quality. For now, many doubts remain.

Abstract

Nasopharyngeal myiasis in red deer has never been studied in Portugal. For this reason, from December 2015 to February 2016 a study was derived on hunted red deer in Idanha-a-Nova county to evaluate the Diptera larvae presence. During the initial examination on the spot, the larvae was analysed at the nasopharynx. When present, larvae were collected for further species identification. The infestation prevalence was 50.6 ± 7.61% (CI 95%), and the mean parasitism intensity was 11.38 larvae per affected host. Two larvae species were found, Pharyngomyia picta and Cephenemyia auribarbis, both on single or concomitant infection, with the first species having a higher prevalence and mean infestation intensity than the second. The larvae’s prevalence was significantly higher (X² = 4.35; p = 0.0370) in males (62.16 ± 11.05%) than in females (41.30 ± 10.06%). Within age groups, younger animals showed a higher prevalence. This study shows the presence of P. picta and C. auribarbis larvae in the wild red deer population in Portugal for the first time. The high parasitic prevalence and mean intensity highlight the importance of this parasitosis in this wild species. For this reason, more scientific research is required to accurately assess its prevalence in other geographic areas, and evaluate the risk factors as well effects of this parasitosis on the deer population.

Typical intracranial myiasis in Nigerian red river hogs (Potamochoerus porcus) caused by an unknown bot fly (Diptera: Oestridae)

We report an unknown taxon of bot fly (Diptera: Oestridae: Oestrinae) in red river hogs (Potamochoerus porcus Linnaeus, 1758) in Cross River State, Nigeria. From direct observation and interviews with local hunters, we document that, remarkably, the parasite typically occurs within the intracranial supra-meningeal space - i.e., between the inner wall of the skull and the brain - but without causing visible inflammation or clinical signs. The parasite is most similar (up to 87.9%) to Rhinoestrus usbekistanicus based on cytochrome oxidase subunit 1 DNA sequencing but is sufficiently divergent phylogenetically to represent a new or previously un-sequenced taxon. Morphologically, the parasite shares some, but not all, features with R. nivarleti. Local cultural belief systems attribute aspects of red river hog behavior (e.g. intelligence, elusiveness) to the parasite, suggesting a prolonged presence in the red river hog population. The parasite's unusual anatomic location may be aberrant, or it may be a protective adaptation to life in red river hogs, which forage vigorously with their snouts.

An Update on Cephenemyiosis in the European Roe Deer: Emergent Myiasis in Spain

Cephenemyia stimulator is a Palearctic species developing in the nasal cavity and pharynx of roe deer (Capreolus capreolus). It is widely spread in the range of distribution of this ungulate in Europe. Since the first report of C. stimulator in Spain in 2001, a rapid geographic expansion has been observed, first in the north of the country, with high prevalence and intensities of infestation that caused some mortal cases, and, lately, also in Extremadura and Andalucía, the southernmost populations of European roe deer. These observations suggest an adaptation of this parasite to different ecosystems of the Iberian Peninsula. Almost simultaneously, C. stimulator is also expanding its range to northern Europe, with the first cases being reported in Sweden. Thus, Cephenemyia stimulator may be an example of a parasite currently displaying distributional changes along its southernmost and northernmost range margins. Thus, it is of the utmost importance to unravel all the epidemiological and clinical aspects of this myiasis, as well as implementing surveillance measures including reliable and non-invasive diagnostic techniques to monitor its expansion and adaptation to different ecosystems and/or hosts and to reduce the negative impact on roe deer populations.

First record of Pharyngomyia picta (Diptera: Oestridae) parasitizing Cervus elaphus in Sierra Nevada National Park

The necropsy made to two adult individuals of red deer shot in Sierra Nevada National Park revealed infestation by second- and third-instar larvae of the oestrid Pharyngomyia picta (Meigen 1824). The animals were shot in Dehesa de las Hoyas, about 2000 m above sea level. This is the first record of this parasite in Sierra Nevada National Park. Furthermore, the occurrence of adult P. picta at this altitude could indicate significant changes of the climatic conditions, now matching better the environmental requirements of this bot fly. Its monitoring may, therefore, be of great help for detecting global change signs.

Major differences in the larval anatomy of the digestive and excretory systems of three Oestridae species revealed by micro-CT

Oestrid flies (Diptera: Oestridae) do not feed during the adult stage, so they depend on an efficient assimilation and storage of nutrients during their parasitic larval stage. We describe the general morphology and provide volumetric data for the digestive and excretory organs of the three larval instars of the nasal bot fly Oestrus ovis L., using micro-computed tomography. The size of the digestive and excretory organs greatly increased across larval instars. In all instars, the two salivary glands were remarkably large and formed a 'glandular band' by coming together, but without lumina uniting, at their posterior ends. The distal region of the anterior Malpighian tubules was greatly enlarged and full of highly radio-opaque concretions. Moreover, the anatomy of O. ovis third-instar larva was compared to that of two species of, respectively, similar and different feeding habits: Cephenemyia stimulator (Clark) and Hypoderma actaeon Brauer. Whereas the general morphology and arrangement of the digestive and excretory systems of C. stimulator was similar to that of O. ovis, some differences were observed in H. actaeon: a swollen anterior region of the midgut, salivary glands shorter and not forming a 'band' and anterior Malpighian tubules narrowly uniform throughout their entire length.

First reports of nasal and traumatic myiasis infection in endangered Przewalski's horses (Equus ferus przewalskii)

Myiasis has great economic and medical importance. However, myiasis in wildlife that is caused by oestroid flies is relatively rarely recorded compared with that in humans and domestic animals. Recently, during our research on the conservation of Przewalski's horse (PH), we observed two new records of oestroid flies parasitizing wildlife in China. The first is the horse nasal bot fly, Rhinoestrus sp. (Diptera: Oestridae), found in a dead PH from Kalamaili Nature Reserve. One morphotype (R. purpureus-like) was identified. The second is the Wohlfahrt's wound myiasis fly, Wohlfahrtia magnifica (Schiner, 1862) (Diptera: Sarcophagidae), which was collected from an open wound of a PH in the Wild Horse Breeding Research Centre. These observations extend the records of known hosts of these two oestroid myiasis agents. To the knowledge of the authors, infestation by Rhinoestrus and Wohlfahrtia larvae causing myiasis in wildlife has not been reported in China previously.

Human Nasal Myiasis Caused by Oestrus ovis in the Highlands of Cusco, Peru: Report of a Case and Review of the Literature

Myiasis is the infestation by dipterous larvae. The larvae can infect intact or decaying tissue including the skin or epithelial surfaces of the orbits, nose, and genitourinary and gastrointestinal tracts. We report a case of primary obligatory nasal myiasis by Oestrus ovis in a 56-year-old man from Cusco in Peru. He presented with nasal pruritus, congestion, and sneezing white "cottony" material. The material was identified as O. ovis larvae. A literature review of publications reporting nasal myiasis caused by O. ovis is presented.

Oestrose: uma parasitose emergente em pequenos ruminantes no Nordeste do Brasil

Resumo: No período de janeiro de 2011 a dezembro de 2014 foram diagnosticados 9 surtos (A, B, C, D, E, F, G, H e I) de Oestrus ovis em pequenos ruminantes no estado da Bahia. No surto A obteve-se 0,5% (1/200); B 2,2% (2/90); C 0,8% (1/120); D 2% (2/100); E 1% (1/100); F 3% (1/33); G 0,6% (1/150); H 2,5% (5/200); I com 11,4% (8/70) em ovinos e 5% (2/40) em caprinos. Os sinais clínicos associados ao parasitismo pelas larvas nos surtos foram respiração ruidosa, espirro seguido de secreção nasal catarral, inquietação, movimentação excessiva da cabeça e andar em círculo. Macroscopicamente havia nos seios e conchas nasais hiperemia, edema da mucosa e presença de larvas. Todas as larvas coletadas dos cornetos e conchas nasais variavam desde o primeiro ao terceiro estágio de desenvolvimento. Algumas larvas L3 coletadas nas necropsias foram incubadas e o imago obtido das pupas mediram aproximadamente 10mm de cor acinzentada e abdômen escurecido. Realizada análise descritiva das condições climáticas, ano e positividade de casos de oestrose, demonstrou que a ocorrência tem tendência de crescimento com os anos (p˂0,001) e que houve casos com menor média de temperatura mínima (p˂0,001), possibilitando o desenvolvimento da mosca de O. ovis, demonstrando que houve a introdução da mosca enTtre o rebanho de ovinos e caprinos do estado da Bahia, e que as condições climáticas são ideais para perpetuação da espécie.

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.

Profiling of proteins and proteases in the products of the salivary gland, digestive tract and excretions from larvae of the camel nasal botfly, Cephalopina titillator (Clark)

Proteins and proteolytic activities in the contents of the salivary gland (SGc), digestive tract (DTc) and excretory-secretory products (ESP) from larvae of the camel nasal botfly Cephalopina titillator were separated electrophoretically, and characterized. The protein profiles of the different samples were qualitatively quite similar in the larval stages L2 and L3. Zymogram analysis of proteases in the samples indicated that the digestive tract contained a greater variety of proteases than the salivary gland or the excretory-secretory products. They are mainly serine proteases. Proteases of ESP and DTc (especially of 3rd instar) contain trypsin- and chymotrypsin-like serine proteases, while the serine proteases of SGc are not of the trypsin- or chemotrypsin-type.

The immunobiology of myiasis infections--whatever happened to vaccination?

The current state of myiasis vaccine technologies are reviewed mainly in the primary research genera of Lucilia and Hypoderma. The importance of myiasis flies as primary causes of morbidity and mortality in agricultural species and man has not diminished despite the existence of good control strategies. However, the development of vaccines against myiasis infections has been relatively quiescent for more than 10 years despite the rapid development of genomic and proteomic analysis and of skills in data interpretation. The value of vaccine research in an era of chemical primacy is analysed. In fact, recent findings of drug resistance and the impact of animal welfare concerns should mean a renewed interest in alternative controls. The reasons that this has not been true to date are explored and new possibilities discussed.

Reliability of an ELISA test for diagnosing oestrosis in Iberian ibex

Oestrosis is one of the most prevalent parasitosis affecting the Iberian ibex, Capra pyrenaica . To date, both the diagnosis of oestrosis and the determination of the intensity of parasitism require the use of invasive methods (necropsy), which necessarily limit research possibilities. We analyzed the immune humoral response (IgM and IgG) against Oestrus ovis L. excretory/secretory larval antigens in 32 sera taken from Iberian ibex from the Sierra Nevada Natural Space (southern Spain). Three antigens were collected: L1OES (from L1 larvae), L2OES (L2), and L3OES (L3). Necropsy was considered as the gold standard. The percentage of ibexes harboring Oestrus spp. larvae was 88%, the mean intensity of parasitism being 16.96 ± 14.96 larvae per parasitized host (range: 2-52). In our sample, first-instar larvae (L1) were found in 9% of ibexes, while 69% of hosts carried L2 larvae and 88% L3 larvae. Positive correlations between L1 and L2 numbers, and between L2 and L3 numbers were detected. The best results with the immunoenzymatic assay were obtained using IgG antibodies against the L1OES antigens (specificity = 89%; sensitivity = 100%; positive predictive value = 100%; negative predictive value = 57%). The IgG seroprevalence against L1OES was 78%. Thus, the analysis of IgG antibodies against antigens collected from L1 O. ovis larvae would seem to be a noninvasive method for reliably diagnosing oestrosis in naturally infested Iberian ibex. Nevertheless, additional immunological and methodological advances are still required because false positive and false negative results still represent a non-negligible part of the results of the ELISA tests.

In vitro and in vivo effects of neem tree (Azadirachta indica A. Juss) products on larvae of the sheep nose bot fly (Oestrus ovis L. Díptera: Oestridae)

Two studies were carried out in order to test the effects of neem tree extracts (Azadirachta indica A. Juss) on sheep bot fly larvae (Oestrus ovis L. Diptera: Oestridae). First, aqueous extracts from neem seeds (ASNE) at 0, 5 y 10% (w/v) concentrations were tested on larval mortality in vitro. In a second study, the effect of oral administration with neem seed meal (0, 100 y 200mg/kg) and neem leaves (1% of diet) on number of larvae found at necropsy and larval development was evaluated in experimentally O. ovis-infected sheep. Results in Experiment 1 showed a significant (P<0.05) effect of ASNE on time to L1 mortality in a dosis-dependent manner. In Experiment 2, oral administration of seeds or leaves did not affect the number of larvae found at necropsy of the sheep, but interfered with larval development and there was a tendency to reduce larval weight at the end of the infection period (55d).

Persistent pediatric gastro-intestinal myiasis: a case report of fly larval infestation with Musca domestica with review of literature

The occurrence of dipterous fly larvae in human is termed as human myiasis. Human myiasis can be classified based on clinical condition it causes like cutaneous myiasis, ocular myiasis, urogenital myiasis and intestinal myiasis. Based on the need for a particular host, myiasis can be divided as specific myiasis, semi-specific myiasis. Accidental myiasis results when the fly larvae are deposited/ingested by human resulting in infestation, which is also called as pseudomyiasis. Fly larvae may be present on the dead and decaying organic matter and domestic animals like dog and cats which are naturally infested with fly larvae and can be source for infection in children. Very few cases have been retrieved from literature on the occurrence of intestinal myiasis in children throughout the world. We report a case of two siblings in the same family infested with dipterous fly larvae.

Nasal eucoleosis in a symptomatic dog from Italy

A dog with chronic muco-purulent nasal discharge, sneezing, reverse sneezing and impaired scenting ability was diagnosed as being affected by nasal eucoleosis based upon rhinoscopic evidence of Eucoleus boehmi in situ, identification of the adult parasites in nasal biopsies, and eggs in the faeces by light and scanning electron microscopy. The dog was successfully treated with a single administration of moxidectin. A second course of moxidectin was required for about 10 weeks after the first treatment, because clinical signs recurred due to a likely re-infection. This second administration, along with measures undertaken to prevent geo- and coprophagic pica, resolved the parasitism, as demonstrated by negative copromicroscopic and rhinoscopic examinations, and prevented reinfestation for the next 4 months. To the best of the authors' knowledge, this represents the first report describing a clinical case of nasal eucoleosis with a demonstration of the adult parasites in situ in a dog from Italy where, until recently, infestation of E. boehmi was only detected by a coprological examination. Veterinarians and parasitologists should be aware of the occurrence of canine infection with E. boehmi. They should include this parasite in the differential diagnoses for animals suffering from upper airway distress and look systematically for it during rhinoscopic and copromicroscopic examinations.

Efficacy of moxidectin long-acting injectable formulation (1 mg/kg bodyweight) against first instar larvae of Oestrus ovis in naturally infected sheep

The objective of the current study was to evaluate the efficacy of a single treatment with a long-acting injectable formulation of moxidectin (MOX) at 1.0 mg/kg bodyweight (b.w.) against natural infection by nasal bots (Oestrus ovis) in sheep with special attention to first instar larvae (L1). Firstly, a local farm with clinical history of oestrosis was chosen to conduct the assay. A total of 49 sheep were pre-selected at the end of the summer according to the presence of evident clinical signs of infection and confirmed later by means of an indirect ELISA against excretory-secretory products from L1 to detect IgG antibodies. After that, 24 sheep were chosen to carry out the study on the basis of positive serology and age since the oldest ones were selected. The day 0 of the assay, the treatment group was administered with the MOX formulation by subcutaneous injection at the base of the left ear and the control group was administered with a saline solution in the same way. All sheep were slaughtered on day 28 post-treatment (pt). At the necropsy, the head of all sheep were cut off and split into two sagital sections and all larvae from nasal passages, septum, middle meatus, conchae and sinuses were recovered. After the necropsy, a significant number of L1 was only found in the control group and therefore the efficacy of the MOX formulation was only calculated against this stage. As a result, the formulation was 90.2% effective against L1 for sheep slaughtered at day 28 pt.

Corrected misidentification of first instars of the bot flies Cephenemyia apicata and C. jellisoni, with a review of the biology and life history of both species

First instars obtained from the uteri of host-seeking females, and compared with previously published descriptions of larvae collected from Columbian black-tailed deer (Odocoileus hemionus columbianus), revealed that larvae described as Cephenemyia apicata Bennett & Sabrosky (Diptera: Oestridae) actually are C. jellisoni Townsend. Several new characters are added to supplement the original descriptions of the first instars of these species. Collections of all larvae from deer autopsied during different months established that the first instars of C. apicata undergo a long obligate period of development and growth in the bronchi before molting and migrating to the retropharyngeal pouches of deer. This is the first study to document an obligatory lung phase in the life history of a species of Cephenemyia. The lung phase of C. apicata is compared with that described for Pharyngomyia picta (Meigen) (Diptera: Oestridae) in European red deer. A literature review found that for all Cephenemyia species studied, as well as for P. picta, a 6-8 month period of development as first instars during the fall/winter months ensures that pupal development and eclosion of adults will occur during periods of favourable external environmental conditions.

Persistent efficacy of a long acting injectable formulation of moxidectin against natural infestations of the sheep nasal bot (Oestrus ovis) in Spain

Cydectin(®) 2% LA Solution for Injection for Sheep (Pfizer Animal Health) is a long-acting (LA) formulation of moxidectin for the treatment and prevention of mixed infections of gastro-intestinal nematodes, respiratory nematodes and certain arthropod parasites in sheep. To evaluate the duration of persistent efficacy against nasal bots (Oestrus ovis), a natural exposure study was conducted in Spain during the summer of 2011. One hundred and twenty nasal bot-free, Rasa Aragonesa sheep were randomly allocated to eight groups of 15 animals each. On Day 0, four groups were treated at the recommended dose rate of 1 mg moxidectin/kg bodyweight. Four groups remained untreated as negative controls. All animals were held in nasal bot-proof housing except for exposure to natural challenge when one group of treated sheep and one of group of control animals were transferred to a local pasture at either 0-20, 20-40, 40-60, or 60-80 days after treatment. Following challenge, sheep were scored for clinical signs of bot infestation, necropsied and the heads sectioned for larval recovery. Nasal bot larvae were retrieved from 7 to 11 control sheep following each exposure period indicating that adult bots were active throughout the study. In the first challenge up to 20 days after treatment, when sheep were slaughtered immediately after exposure, the majority of larvae were first instar (L1) and only 3 of the 15 control sheep were infested with second instars (L2). There was 100% efficacy against L2 and 38.1% reduction in the number of live L1 in the treated sheep but mean counts were not significantly different between treatment and control groups (P ≥ 0.05). For the subsequent exposure periods 20-80 days after treatment (necropsies 7-9 days after challenge), 6-10 sheep were infested with L1 and 9-11 control sheep were infested with L2 and third instars (L3). There was negligible efficacy against L1, but treatment with moxidectin resulted in 100% control of L2 and L3. These results are consistent with the biology of nasal bots and control with a systemic agent, as the slower growing L1 have limited feeding and are therefore less susceptible to systemic parasiticides. The study demonstrated that the persistent efficacy of this long-acting injectable formulation of moxidectin protects against the development of active O. ovis infestations for at least 80 days after treatment.

The Curious Connection Between Insects and Dreams

A majority of humans spend their waking hours surrounded by insects, so it should be no surprise that insects also appear in humans’ dreams as we sleep. Dreaming about insects has a peculiar history, marked by our desire to explain a dream’s significance and by the tactic of evoking emotions by injecting insects in dream-related works of art, film, music, and literature. I surveyed a scattered literature for examples of insects in dreams, first from the practices of dream interpretation, psychiatry, and scientific study, then from fictional writings and popular culture, and finally in the etymology of entomology by highlighting insects with dream-inspired Latinate names. A wealth of insects in dreams, as documented clinically and culturally, attests to the perceived relevance of dreams and to the ubiquity of insects in our lives.

Oestrus ovis infestation of a dog in the UK

In March 2011, a dog on a sheep farm in the Cotswolds, UK, expelled a mature live third-stage larva of the sheep nasal botfly, Oestrus ovis, after a violent and traumatic sneezing episode. The dog had been infected with first-stage larvae deposited by an adult fly the previous autumn; larval development had progressed throughout the winter and spring with few apparent clinical signs and possibly masked by ongoing immunotherapy for an unrelated condition. Identification of the parasite at the Liverpool School of Veterinary Science was made from a submitted puparium, the "chrysalis" stage to which the larva had progressed within days of its expulsion from dog's nose. To the authors' knowledge this is the first report of nasal botfly infestation of a dog in the UK.

Naso-pharyngeal mites Halarachne halichoeri (Allman, 1847) in Grey seals stranded on the NW Spanish Atlantic Coast

In North Atlantic European waters, the nasal mite Halarachne halichoeri has been described affecting Grey seals (Halichoerus grypus) producing different levels of respiratory disease. This study provides data on the prevalence, clinical signs and produced macro-pathology of this parasite mite infecting juvenile wild Grey seals stranded in North-Western Spanish coast. Among the 25 seals examined during the study, a total of 19 had nasal mites in their respiratory upper ways, including adult and larval stages. This represented a percentage of prevalence of 76 ± 8.37. All the live positive seals presented a typical clinical symptomatology associated to upper respiratory tract infections. In dead positive seals, a light to intense sinusitis could be diagnosed macroscopically. The presence of the parasite in the nasal sinuses appears as the primary cause of the high respiratory tract symptomatology presented in most of the juvenile seals stranded in the north coast of Spain. Ultrastructural characterization by scanning electronic microscopy (SEM) has confirmed the taxonomic status of the mite. This identification of H. halichoeri represents the first description of the occurrence of this parasite in Southern Europe.