Oestrus Ovis Research Articles

Nasopharyngeal Botflies Oestrus ovis and Cephenemyia stimulator in Roe Deer (Capreolus capreolus) from Northern Spain.

Two of 19 roe deer (Capreolus capreolus) in northern Spain were infested with Cephenemyia stimulator and one individual with Oestrus ovis. Three larvae of O. ovis were recovered from the nasopharynx of an adult female deer examined in February 2017, during the hunting season in the province of Burgos. The larvae were identified by morphology, and DNA sequencing from cytochrome oxidase subunit I and 28S rDNA confirmed the identification of both species of larvae. The possibility of O. ovis parasitizing roe deer should be considered in the diagnosis of nasal bots in cervids.

Ophthalmomyiasis externa caused by oestrus ovis: A case report

Ophthalmomyiasis, fly larvae infestation of eye, is a rare condition that can have variable presentation depending on the type of fly, ocular structures involved, and level of penetration. A case of ophthalmomyiasis externa presented with foreign body sensation, itching, and redness of eyes for 2 days was documented. Mechanical removal and good local treatment helped the patient. The larva isolated was that of Oestrus ovis (sheep nasal botfly). Ophthalmomyiasis externa is mainly caused by sheep botfly O. ovis and it is more common in farming communities. This infestation is rare in India as very few cases are on records.

Theoretical and experimental studies on the electrochemical behavior of steel in HCl solution in the presence of two bio-inhibitor mixtures

In this new study, the inhibitory effectiveness of two bio-inhibitor mixtures has been studied on the corrosion characteristics of carbon steel in an HCl environment. The inhibitors were derived from a plant seed (quinoa seed-QS) and an insect extract (Oestrus ovis larvae-OOL). The total inhibitor concentration was a variable factor even the ratio of bio-inhibitor concentration was a fixed parameter. The electrochemical behavior of steel substrate was investigated through the Tafel polarization and electrochemical impedance spectroscopy measurements. Fourier transform infrared spectroscopy and field emission scanning electron microscopy were performed to identify bonds and analyze the morphology of the corroded surface of the steel. Additionally, molecular dynamics (MD) simulation and quantum calculations were applied to investigate the inhibitory influence of utilized bio-inhibitors. The experimental results indicated that the corrosion resistance decreased to 85 % when the optimum total concentration of the bio-inhibitor was 1 g L−1. The Langmuir model was used to illustrate the adsorption mechanism on the steel surface when physical adsorption occurred. Quantum chemical calculations revealed that the QS-inhibitor adsorbed more effectively onto the metal surface than the OOLE-inhibitor, due in part to a lower energy gap and higher HOMO energy. MD simulation and Monte Carlo calculations further confirmed that the QS-inhibitor was adsorbed on the Fe (110) surface with higher adsorption energy than the OOLE-inhibitor.

First Molecular Diagnosis of Oestrus ovis (Linnaeus, 1758) Larvae Causing Conjunctival Ophthalmomyiasis in Mexico City, Mexico.

Human ophthalmomyiasis is a rare ocular parasitosis that results from the accidental infestation of dipteran larvae of several species, including Oestrus ovis (Linnaeus, 1758). This study aims to present the fourth documented human case of ophthalmomyiasis in Mexico, identifying the etiological agent through morphological and molecular analyses. Additionally, we investigated the phylogenetic position and genetic distances among different specimens globally characterized based on mitochondrial Cox1 sequences. A total of five larval specimens were extracted from the patient's eye, with two specimens allocated for identification based on morphological features using a stereomicroscope, and the remaining three preserved in absolute ethanol, one of them used for subsequent analysis using molecular methods. The mitochondrial Cox1 region was amplified and sequenced using automated Sanger sequencing. The resulting sequence was deposited in GenBank under accession number OR440699 and subjected to BlastN analysis against 35 other Cox1 sequences of O. ovis from GenBank. The identity and phylogenetic position of the strains were further explored using parsimony and maximum likelihood phylogenetic methods. Morphological examination of the larval specimens extracted from the patient's eye unequivocally identified them as O. ovis species. BlastN analysis and comprehensive phylogenetic investigations involving a total of 36 Cox1 sequences confirmed the taxonomic identity of the larvae. Notably, our sequence was positioned within the cluster formed by the Brazilian and two Iranian samples. This finding underscores a shared genetic ancestry among these distinct geographical isolates and provides valuable insights into the evolutionary relationships within O. ovis populations. The presence of O. ovis infestation in Mexico City suggests potential shifts in environmental conditions favoring fly proliferation, highlighting the need for vigilance in urban healthcare settings.

Immunogenic Proteins Characterization in the Larvae of Oestrus ovis by Western Blot Analysis

The present study was undertaken to characterize and identify immunogenic proteins of Oestrus ovis in Telangana. Oestrus ovis is the most predominant nasal bot fly causing nasal myiasis in India. The collected larvae from Jiyaguda slaughter house, Hyderabad are seperated into L2 and L3 larvae were washed with normal saline and PBS pH 7.4 and preserved at -70°C for antigen preparation and some were preserved in 70 % ethanol for identification. The larvae were speciated by light microscopic examination based on morphological features such as ventral spines, anterior hooks and “D” shaped posterior spiracles. In this study, an antigen was prepared from second and third instar larvae of Oestrus ovis using a soluble buffer solution. The resulting Crude Somatic Larval (CSL) antigen had a protein concentration of 27.4 mg per ml. The CSL antigen was resolved in 8% SDS-PAGE, Immunoblotting was performed by electro transferring the separated polypeptides onto a nitrocellulose (NC) membrane. Treatment with specific reagents and antibodies resulted in the identification of 19 immunoreactive polypeptides, with molecular weights matching those observed in SDS-PAGE. Four polypeptides with molecular weights of 58.56, 20.74, 19.09, and 28.91 kDa exhibited the strongest reaction towards the antibodies raised against CSL antigen. These four polypeptides are considered promising candidates for future immunizations and testing their protective efficacy through in vivo assays. These findings have implications for advancing strategies to combat myiasis, a parasitic disease caused by Oestrus ovis larvae.

External ophthalmomyiasis caused by oestrus ovis larvae

A 17 year-old man presented with redness, foreign body sensation, and itching in his right eye for a day after some dust particles fell into his eyes. On slit lamp examination of the right eye, multiple, small, translucent mobile worms; papillary conjunctival congestion; and symblepharon formation at 6’o clock with features of chronic conjunctivitis were seen over both bulbar and fornicial conjunctiva. The worms were picked up under topical anesthesia and sent for the parasitological examination, which reported it to be the larval (Oestrous ovis) of the sheep botfly. The patient was reviewed every day for a week for removal of larvae from the eye along with use of betadine eyedrops and antibiotic steroid combination.

Morphological and Molecular Detection of Oestrus ovis Isolated from Goats in Babylon Province, Iraq

Morphological and Molecular Detection of Oestrus ovis Isolated from Goats in Babylon Province, Iraq

Prevalence of nasopharyngeal myiasis in roe deer (Capreolus capreolus) from an area with high sympatry between wild and domestic ungulates in Central Spain

Infestation by the sheep bot fly Oestrus ovis was firstly reported in a single roe deer from Central Spain in 2022. For assessing the current situation of nasal myiases in this ungulate in this area, the nasopharyngeal cavities of 184 roe deer hunted in Central Spain between January-June 2023 were examined. All larvae were recovered and morphologically identified; in addition, species identification was molecularly confirmed in a subset of specimens. Forty-four roe deer (23.9%; CI 95 17.95–30.74) were positive for different Oestrinae larval stages. Twenty-six animals (14.1%; CI 95 9.44–20.02%) were infested by the roe deer nasal bot fly (Cephenemyia stimulator) with a mean intensity of 35.2 (SD 49.71) larvae/infested animal, and eighteen (9.8%; CI 95 5.90-15.02%) roe deer harboured the sheep bot fly (O. ovis), with a mean intensity of 2.0 (SD 1.33) larvae/infested animal. No mixed infestations by both Oestrinae were found in a single animal. All larval instars (L1, L2 and L3) of both species were identified. Most C. stimulator specimens were located at the nasal turbinates, and a small percentage (3.2%) at the pharynx; all O. ovis larvae were found at the nasal turbinates. Since O. ovis is highly prevalent in sheep and goat flocks from Central Spain, the high sympatry between roe deer and small ruminant populations in the studied area may have increased the risk of cross-infection. Moreover, the finding of mature L3 of O. ovis suggests that this species can complete its life cycle in roe deer. Therefore, monitoring bot flies in sheep and goat flocks as well as in sympatric wild ruminants is strongly recommended for achieving an optimum control of nasal myiases.

Prevalence and Histological Study of Oestrus ovis Larvae in Slaughtered Goat of Babylon City, Iraq

This study was carried out to investigate the prevalence of larval stage Oestrus ovis conducted during the period from September 2023 to the end of March 2024 at Babylon city, Iraq. 250 goats firstly were examined grossly and postmortem by longitudinally cutting with a manual saw, secondly, the collected larvae (45) were examined microscopically to measure its length and overall morphology. The total infestation rate was 26% (65/250). The highest rate of infestation was in female which was 44/150 (29.3%) while in male the infestation rate was 21/100(21%). The rate of infestation increases with the progression age of animal, older adult (over three years) was more susceptible to infestation was recorded 30/85(35.3%), while 17% (14/80) were in ages less than one year. Therefore, it showed a highly significant difference at (P<0.01). Furthermore, the histopathological sections of nasal cavity showed that Numerous mucous glands, thickening of epithelium, hyperplasia of blood vessels and severe Infiltration of inflammatory in goat infected with O.ovis larvae. In contrast, the uninfected goat showed moderate inflammatory cell infiltration in mucosal layer of nasal cavity and several dense glandular aggregates encircled by a dense network of elastic fibers. In conclusion, this study shows the important of O. ovis that infect goat in Babylon city, Iraq. Moreover, the morphology of all larval stage is similar except their measurement, color, and the shape of respiratory spiracles.

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

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

More than “just a red eye”: A case series of Oestrus ovis ocular infestation

This case series intends to highlight clinical signs and symptoms of external ophthalmomyiasis caused by larvae of Oestrus ovis. Data were collected from January 2022 to January 2023 at a tertiary eye care center in central India regarding presenting features of patients with external ophthalmomyiasis. In total, 59 cases of established ophthalmomyiasis with a similar organism were recorded. An acute red eye can be caused by a wide spectrum of pathologies, some being as uncommon as a fly larva. Hence, it is important to perform a thorough ophthalmic examination in all patients presenting with inflamed red eyes of unknown cause.

Seasonality of Oestrus ovis infection in sheep in the steppe zone of the Stavropol Territory

The purpose of the research is to study the seasonality of Oestrus ovis infection in sheep depending on the management conditions in the steppe zone of the Stavropol Territory.Materials and methods. The research to study the botfly flight seasonality was conducted on two farms in the Apanasenkovsky District and two farms in the Ipatovsky District of the Stavropol Territory. The number of sheep botflies was studied in the entire flight season by regular inspection and counting of the parasite adult stage on the outer surfaces of sheephouse walls and the side walls of sheds with a 15 day-interval.Results and discussion. The sheep botfly flight season was 5.5 months (from May 25–30 to October 31–November 11). Two increases in the number of botflies were observed during this period: in July and September–October. Infection of sheep with oestrosis in 1971 had two peaks (the first, May to June; the second, August to November). Due to the earlier spring 2022, the first peak started in the second half of March and lasted until the first half of July, and the second peak was observed from the second half of August to the end of November.

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.

Prevalence and seasonal aspects of parasitism by Oestrus ovis (Diptera: Oestridae) in sheep from Mato Grosso State, Brazil.

Oestrus ovis larvae are obligate parasites of vertebrates and cause cavitary myiasis (oestrosis) in sheep and goats. It is also reported as a zoonosis causing ophthalmomyiasis and nasopharyngeal myiasis. Despite being relatively common in Brazil, epidemiological studies on O. ovis are scarce. Considering that the infestation is influenced by the climate and biomes of the studied region, we aimed to investigate the seasonal prevalence of O. ovis among slaughtered sheep in the northern region of the state of Mato Grosso, Brazil. The heads of sheep (n=697) slaughtered at a slaughterhouse in the municipality of Terra Nova do Norte (November 2011 to November 2013) were collected to count, catalog, and identify the larvae found in the upper respiratory tract. Overall, 45.77% (319/697) of the animals were infested with 2,412 recovered larvae, 96.89% (2,337/2,412) of which were identified at the species level as O. ovis. Seasonal variations in prevalence ranged from 41% (spring) to 56% (summer); however, no correlation was observed between prevalence and season, mean humidity, or temperature. In conclusion, parasitism by O. ovis in sheep in the studied area, occurs year-round, considering the occurrence of larvae (L1, L2, and L3) throughout the year, probably because of the area's environmental conditions.

COMPARATIVE EXTENSITY AND INTENSITY OF ESTROSIS IN SHEEP DEPENDING ON ANTIPARASITIC TREATMENTS

The period from the beginning of spring to the end of October is the most dangerous period for sheep. It is at this time that sheep gadflies (Oestrus ovis) are activated, which lay larvae in the nasal cavity of animals. In the future, parasites attack the nasal mucosa, frontal, horny and maxillary sinuses. In the body of a sheep, more than 100 larvae can remain from the vital activity of just one female gadfly, which bother the animal throughout the year. Infection with larvae of sheep gadfly is called «estrosis of sheep». It is dangerously high risk of infection, inflammation of the nasal cavity and even the lining of the brain, which leads to a decrease in productivity and the death of livestock. The latest reports on the spread of sheep gadfly and seasonal dynamics of the level of gadfly infestation in sheep in the southern region of Russia by the beginning of our research were more than a decade ago. The objective of our research was to study the extent and intensity of the invasion of sheep estrosis in the arid zone of the Stavropol Territory, in connection with climatic changes and the ongoing spring chemotherapy with ivermectin drugs against helminthiasis in young sheep. We have been monitoring the clinical manifestations of sheep estrosis over the past three years in sheep farms of the steppe zone of Apanasenkovsky and Ipatovsky districts of the Stavropol Territory. In recent years, the duration of the summer of the imago gadfly has been extended to 8 months due to an earlier stable increase in temperature above +15 oC. Already at the end of March at the beginning of April and the end of the mass summer of the imago gadfly until the end of October, as a result of which two generations of the band gadfly are developing.

Ophthalmomyiasis Externa and Importance of Risk Factors, Clinical Manifestations, and Diagnosis: Review of the Medical Literature.

This review aims to describe and compare the risk factors, clinical course, diagnosis, and parasitologic features of external ophthalmomyiasis. We also discuss the different preventive measures and the effect of global warming in a large case series reported from January 2000 to December 2022. We perform a literature review of reported cases of external ophthalmomyiasis to determine the clinical characteristics, therapeutic management, and information on the organisms that most commonly cause external ophthalmomyiasis. A total of 312 cases of external ophthalmomyiasis were recorded. The most common causative organism was Oestrus ovis (Linnaeus) (Diptera: Oestridae), accounting for 72.1% of cases, followed by Dermatobia hominis (Linnaeus Jr. in Pallas, 1781) (Diptera: Oestridae) at 5.4%, Lucilia sericata (Meigen) (Diptera: Calliphoridae) at 0.96%, and Chrysomyia bezziana (Villeneuve) (Diptera: Calliphoridae) at 0.96%. Before experiencing symptoms, 43.6% of cases reported having direct contact with flies or being hit in the eye, 33% reported no associated risk factors, 9.3% reported living with sheep and goats, and 7.7% reported a history of foreign objects entering the eye. The most common symptoms for those affected by O. ovis were sudden onset, including a foreign body sensation and movement, redness, tearing, itching, swelling, irritation, photophobia, burning, and ocular secretion. In cases caused by D. hominis, symptoms included eyelid edema, pain, redness, itching, movement within the lesion, ocular irritation, and discharge. Regarding occupational or recreational activity, agriculture, and livestock had the highest incidence, followed by trades and technical activities, being a student, and having traveled to an endemic region for work or recreation. Patients with red eyes may suffer from external ophthalmomyiasis, which requires a thorough examination to diagnose and treat it early. Moreover, as the temperature increases due to climate change, it is essential to consider how this will affect the spread of different pathogens.

Retrospective study of Oestrus ovis larvae infestation in small ruminants in Grenada, West Indies

Oestrosis is a nasal cavity myiasis caused by Oestrus ovis larvae from Oetrus ovis diptera flies in small ruminants. The presence of the larvae in the nasal cavity is known to cause rhinitis and sinusitis which can negatively impact the productivity of small ruminants. The aim of the present study was to estimate the prevalence of Oestrus ovis larvae infestation in sheep and goats presented for necropsy. We reviewed necropsy records of sheep and goats submitted to the Veterinary Pathology diagnostic laboratory at St. George's University from 2001 to 2017. Out of 104 goat necropsy cases, Oestrus ovis larvae were observed in 8 goats giving a prevalence of 7.7% (95% confidence interval (CI):3.38% to 14.6%). Similarly, from the 47 sheep necropsies, Oestus ovis larvae were observed in 4 sheep (8.5%) (95% CI: 2.83% to 20.46%). There was no significant difference in Oestrus ovis larvae infestation rates between sheep and goats (p = 1.000, Fisher's exact test). Oestrosis was an incidental finding in all the small ruminants examined at necropsy. This is the first report on Oestrus ovis larvae infestation in small ruminants in Grenada.

Oestrus ovis sinusitis in a dog

AbstractA 2‐year‐old, female Cane Corso was presented for chronic epistaxis, reverse sneezing and purulent nasal discharge. Clinical examination was unremarkable. Bloodwork revealed a mild anaemia. Computed tomography of the nasal cavity was consistent with right frontal sinusitis with suspected foreign bodies. Surgical approach of the right sinus by frontal osteotomy allowed to perform an endoscopically guided extraction of a 15‐mm white ringed worm and multiple black worm‐like structures. The evaluation by an EVPC diplomate confirmed an Oestrus ovis infestation. After endoscopic lavage of the frontal sinus, the dog went home with an ivermectin‐based treatment. It was presented 7 months later for a recurrence of the clinical signs. Tomography and surgical approach to the right frontal sinus revealed persistent presence of the O. ovis infestation. After surgical removal of the parasite and oral isoxazoline treatment, the dog had no signs of clinical recurrence. Follow‐up computed tomography scan confirmed complete resolution of the sinusitis.

"Ocular Myiasis by Oestrus Ovis in Portugal: A Case Report"

"Ocular Myiasis by Oestrus Ovis in Portugal: A Case Report"

External ophthalmomyiasis caused by larvae of Oestrus ovis

External ophthalmomyiasis caused by larvae of Oestrus ovis