Traumatic myiasis of horses caused by Wohlfahrtia magnifica.

A survey was carried out in three stud farms with grazing animals, in order to gather data on the prevalence and clinical manifestation of, and the fly species involved in, traumatic myiasis of horses in Hungary. This parasitic disease was recorded in each farm. On the whole, 9.0% (14) of the inspected horses were infested with fly larvae. The affected horses had one infested lesion only, located at the mucosa of the vulva or the vaginal vestibule. The clinical symptoms depended on the age of infestation. Wohlfahrtia magnifica (Diptera: Sarcophagidae) was the only myiasis-causing fly species identified. It was assumed that unknown volatile chemicals might be responsible for the attraction of gravid females to the undamaged vulvar region. These odours are supposed to be produced during different physiological and/or pathological events associated with oestrus, prolonged puerperal period or inflammation of tissues. Daily inspection of grazing horses and early treatment of the affected areas are needed to avert significant damage to the infested horses.     

Wohlfahrtia magnifica (Schiner, 1862) Diptera: Sacrophagidae) causing a vaginal myiasis in domesticated two-humped camels in the Mongolian People's republic]

Wohlfahrtia magnifica (Schiner, 1862) [Diptera: Sarcophagidae] was established as the causal agent of a vaginal myiasis in female camels in the Mongolian Democratic Republic. Changes of the genitals occur nearly the beginning of June, 4-6 weeks after foaling, a spontaneous recovery is seen at the beginning of October. Clinical signs of the vaginal myiasis and morphology of the three stages of larvae are described in detail.     

Myiasis caused by Wohlfahrtia magnifica (Schiner, 1862) in the Arabian camel (Camelus dromedarius) in the Peninsula of Sinai

Massive myiasis caused by Wohlfahrtia magnifica (Schiner, 1862) in camels in the Southern Mountainous zone of the Peninsula of Sinai is described. Wohlfahrtiosis seemed intimately related to the climatic and ecological conditions of the area, particularly altitude, precipitation, pasture, rodents and ticks. The clinical features resembled those described in sheep in Israel and in camels elsewhere. Treatment with diazinon and synergized pyrethrum in pine oil proved effective.     

The investigation of lipid peroxidation, anti-oxidant levels and some hematological parameters in sheep naturally infested with Wohlfahrtia magnifica larvae

Wohlfahrtia magnifica is the main agent of traumatic myiasis in many central and eastern European countries as well as in the Mediterranean basin and Asian countries. The present study was aimed to investigate the effect of myiasis infestation on lipid peroxidation, antioxidant levels and several hematological parameters in the sheep naturally infested with W. magnifica larvae. A total of 38 sheep, including 19 awassi sheep naturally infested with W. magnifica larvae and 19 clinically healthy awassi sheep, were studied. The infected animals were divided into three groups depending on the number of larvae (Group 1: <50 larvae; Group 2: 50-100 larvae; Group 3: >100 larvae). In blood samples, red blood cell counts, hemoglobin, hematocrit concentration and white blood cell, neutrophil, lymphocyte, eosinophil, basophil counts, plasma malondialdehyde, erythrocyte glutathione levels and erythrocyte glutathione peroxidase activity were studied. The results revealed a marked decrease in red blood cell counts and hemoglobin concentrations along with a significant increase in white blood cell and neutrophil counts. The elevation in plasma malondialdehyde levels, a function of lipid peroxidation, established a significant difference between the control group and groups 2, 3. Decreased activity of erythrocyte glutathione peroxidase was found significant in the control group and all parasitemia. We conclude that in natural infestations with W. magnifica, as in infestation with Lucilia cuprina, there is a notable increase in inflammatory activities resulting from the movements, secretions, and toxins of the larvae and form the toxins secreted by the bacteria - which leads to an impression of anemia - and that the tissue injury results in an increase in level of free radicals in the organism.     

Oestrus ovis myiasis in Libyan sheep and goats

Summary The heads of 1,489 sheep and 320 goats were examined for larvae ofOestrus ovis at 17 abattoirs in northern Libya in July to November 1988. The prevalence ofO. ovis in sheep was 22·6% and in goats it was 18·4 per cent. Up to 14 and 11 larvae were collected from individual sheep and goats respectively. All larvae were recovered from the nasal passages and frontal sinuses, but only second and third instars were seen.

---

Miasis Causada PorOestrus Ovis En Ovejas Y Cabras Libias

Resumen Durante los meses de julio a noviembre de 1988, se examinaron las cabezas de 1489 ovejas y 320 cabras para detectar larvas deOestrus ovis, en 17 mataderos en el norte de Libia. La prevalencia deO. ovis en ovejas fue de 22·6% y en cabras de 18·4%. Se localizó hasta un máximo de 14 y 11 larvas en cabezas ovinas y caprinas respectivamente. Todas las larvas fueron recuperadas de las fosas nasales y los senos frontales; sólo se encontraron los estadíos larvarios segundo y tercero.

---

Myiase A Oestrus Ovis Chez Des Ovins Et Caprins En Libye

Résumé Les têtes de 1 489 moutons et de 320 chèvres ont été examinées dans 17 abattoirs de la Libye du nord, de juillet à novembre 1988, pour rechercher des larves d'Oestrus ovis.La prévalence d'Oestrus ovis chez les moutons était de 22,6 p. 100 et chez les chèvres de 18,4 p. 100. Le nombre maximal de larves trouvées par animal a été de 14 chez les moutons et 11 chez les chèvres. Toutes les larves ont été récoltées des conduits nasaux et des sinus frontaux, mais seuls les deuxièmes et troisièmes stades ont été observés.

     

Current trends in screwworm myiasis in the Caribbean region

In a random sample of animal producers and animal health personnel, 33% of the respondents in Trinidad, 15% in Guyana, 11% in Suriname and 9% in Jamaica recalled at least one case of human myiasis due to Cochliomyia homivorax (Coquerel). During 1981, respondents in Surinam (88%), Jamaica (90%), Guyana (85%) and Trinidad and Tobago (82%) found at least one case of myiasis in their livestock, occurring mainly in cattle, pigs and dogs. Feral animals, e.g. jaguars, were also found to be infested. The initial wounds were mainly the umbilicus of neonates, and arbitrary wounds, and vampire bites were also affected. Fifty-three to 78% of all respondents examined their livestock daily for wounds and infestation by the screwworm. Annual estimates of losses (in U.S. dollars) due to surveillance and medication ranged from $4.82 to $10.71 per animal. Nationally, these losses amount to $0.30 million (Surinam), $1.02 million (Trinidad and Tobago), $4.33 million (Guyana) and $6.78 million (Jamaica). Figures for other losses, arising from failure to thrive, reduction in milk production and hide injury due to screwworm activity were not available. Most producers found that the greatest screwworm infestation occurred in the wet season, and most described it as second in importance to Boophilus spp. ticks as a pest of livestock, but of greater significance than biting flies, such as tabanids and stable flies. Eradication of the screwworm from the islands of Jamaica and Trinidad and Tobago can be recommended, but in Surinam and Guyana eradication seems feasible only on the 100-km wide coastal strips where most human and livestock populations exist.     

Species composition of Gasterophilus spp. (Diptera, Oestridae) causing equine gastric myiasis in southern Italy: parasite biodiversity and risks for extinction

Horse gastrointestinal myiasis caused by larvae of Gasterophilus spp. (Diptera, Oestridae) flies has a worldwide distribution and, where present, it is primarily caused by larvae of Gasterophilus intestinalis and Gasterophilus nasalis. Other species, i.e., Gasterophilus inermis, Gasterophilus pecorum and Gasterophilus haemorrhoidalis, present in different or in the same regions of the gastrointestinal tract, were only occasionally reported in very limited areas of eastern European Countries and in central Italy. With the aim to contribute data on the species composition of Gasterophilus and on the seasonal variation of the infection pattern in southern Italy, 152 native horses were necropsied from January to December 2003 and Gasterophilus larvae were collected from the stomach, the small intestine and the rectum of each of them. On the whole, 125 (82.2%) horses were infected by larvae of Gasterophilus spp. and 214 second stage larvae (L2) and 13,342 third stage larvae (L3) collected. Five species of Gasterophilus were identified with the following prevalence: G. intestinalis=95.2%, G. nasalis=44.8%, G. inermis=15.2%, G. pecorum=2.6% and G. haemorrhoidalis=0.8%. L3 were retrieved throughout the observation period with the highest mean burdens from January to August 2003 while the lowest mean was registered from September to November 2003. L2 were collected in February-March 2003 and from September to December 2003. The majority of the animals (n=66, 43.4%) were infected with a single Gasterophilus species, however, 45 animals (29.6%) harboured 2 species, 12 animals (7.9%) 3 species and 2 animals (1.3%) 4 species. The trend of abundance in the L3 of G. intestinalis and G. nasalis, the most represented species, was highly concordant (r=0.5, p<0.001). A retrospective comparison of our results and of other data from four seasons of observation (1983-1986) in central Italy showed that the number of G. inermis, G. pecorum and G. haemorrhoidalis have been decreasing relative to G. intestinalis and G. nasalis which may suggest tendency toward the extinction of the three former species of Gasterophilus.     

Przhevalskiana silenus myiasis among slaughter goats in northern Jordan

During the period December 1998-May 2000, 900 local goats slaughtered at the Irbid Abattoir (northern Jordan) were examined for the larval instars of Przhevalskiana silenus. Of 900 goats, 10% (95% CI: 9,13) were infested with P. silenus larvae. Only the second and third larval instars were seen. A multiple-regression analysis (with the error variance described by the negative-binomial function) suggested that infestation depended on the month of sampling, and that infestation with live larvae was associated with a poorer carcass. The percentage of infested goats and the mean monthly total number of larvae per goat peaked in samples taken in the autumn and winter. Larval numbers were highly aggregated: most animals had no larvae but the maximum was 69. Analysis of the pattern of aggregation suggested that the best model fit was one in which the larvae counts per goat varied with the monthly prevalence.     

Oestrus ovis larval myiasis among goats in northern Jordan

From December 1998 to December 1999, heads of 520 local goats slaughtered at the Irbid, Ramtha and Howarra Abattoirs (northern Jordan) were examined for the three larval instars (L(1)-L(3)) of Oestrus ovis. Of 520 heads, 126 (24%) were infested with O. ovis larvae. All three larval instars were observed in both sexes; all age groups were infested in each month of the year. The mean age of the goats sampled was 1.5 years. The numbers of parasites infesting hosts showed a significant (P<0.05) correlation with sheep age (r(sp)=0.31-0.42) for all three larval instars. The numbers of larvae in each host followed an overdispersed distribution, which fit a negative-binomial model (but not a Poisson distribution). There were more parasites recorded in the presence of purulent discharge or laryngitis, fewer in the presence of catarrhal discharge and no association with pharyngitis sinusitis, or rhinitis.     

Nasal myiasis in a cat caused by larvae of the nasal bot fly, Oestrus ovis

An 8-year-old desexed male Burmese cat, which lived on a sheep-grazing property in central New South Wales, Australia, was presented following the sudden onset of dyspnoea, moist coughing and violent sneezing. The respiratory distress started several hours after the cat had made an outdoor excursion. Anterior rhinoscopy demonstrated small, white objects moving across oedematous and moderately inflamed nasal mucosa. These were retrieved via a series of vigorous nasal flushes and subsequently identified as larvae of the nasal bot fly, Oestrus ovis. The cat was treated with ivermectin followed by selamectin 7 days later. It went on to make a complete recovery over 2-3 weeks.