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P. Dorchies - One of the best experts on this subject based on the ideXlab platform.
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cellular and humoral local immune responses in sheep experimentally infected with Oestrus Ovis diptera oestridae
Veterinary Research, 2003Co-Authors: Guillaume Tabouret, P. Dorchies, Caroline Lacroux, Olivier Andreoletti, Jean Paul Bergeaud, Yacob Hailutolosa, H Hoste, F Prevot, C Grisez, Philippe JacquietAbstract:Cellular and humoral local responses were investigated following repetitive artificial Oestrus Ovis infections in lambs. The presence of larvae induced a huge local recruitment of either leucocytes (T and B lymphocytes, macrophages) or granulocytes (eosinophils, mast cells and globule leucocytes). This cellular response was more pronounced in the ethmoid and sinus (development sites of second and third instar larvae) than in the septum or turbinates where first instar larvae migrate. Infected lambs produced Oestrus Ovis specific IgG and IgA antibodies in their mucus. This local humoral response was mainly directed against larval salivary gland antigens and not against larval digestive tract antigens. Compared to the control animals, the sinusal mucosa of infected animals was extremely thickened and the epithelium exhibited hyperplasia, metaplasia and eosinophilic exocytosis. The possible roles of these local immune responses in the regulation of O. Ovis larvae populations in sheep are discussed.
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seroprevalence of Oestrus Ovis infection in sheep in southwestern germany
Veterinary Parasitology, 2002Co-Authors: C Bauer, F Prevot, G Steng, P. DorchiesAbstract:The aim of the survey was to determine the seroprevalence of Oestrus Ovis infection in flocks in southwestern Germany. Serum samples collected from 1497 sheep (>6 months of age) of 110 flocks in 1997 and 1998 were examined for antibodies to crude somatic antigens of O. Ovis second-stage larvae using an ELISA test. Data on the farm management were obtained by a questionnaire. Overall, 76% of the flocks had at least one seropositive animal, and the seroprevalence of anti-Oestrus antibodies was 50% in sheep. Flock size was the only risk factor significantly associated with the detection of antibodies. Larger flocks (>50 ewes) were more likely to be seropositive than smaller ones. These results show that Oestrus infections are widespread in sheep in southwestern Germany. Further investigations are required to estimate the economic importance of oestrosis and the efficiency of control measures.
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genetic structure of Oestrus Ovis populations in sheep and goats
Veterinary Parasitology, 2002Co-Authors: C Grisezduranton, P. Dorchies, J Jourdane, P DurandAbstract:Abstract A genetic analysis using RAPD markers was performed on 12 natural populations of Oestrus Ovis (Linne, 1761). Three-hundred and six O. Ovis larvae (first, second and third instars) were randomly recovered in nasal cavities of sheep and goats naturally infected in Algeria, Ethiopia, France, Mauritania, Rumania and Tunisia and were analysed by 56 RAPD fragments. The results showed a high diversity within all samples. A significant genetic divergence was showed by discriminant analyses among the 12 populations sampled (p
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Oestrus Ovis in sheep relative third instar populations risks of infection and parasitic control
Veterinary Research, 2001Co-Authors: Guillaume Tabouret, P Jacquiet, Philip J Scholl, P. DorchiesAbstract:Oestrus Ovis (L.) (Diptera: Oestridae), the nasal bot fly, has a relatively short free-living life cycle outside of the host, and therefore it is necessary to know when the parasitic period occurs in order to prevent the clinical signs and economic losses caused by this parasite. The length of this parasitic portion of the life cycle is quite variable: a few weeks to several months depending on the season and climatic conditions. Surveys of Oestrus Ovis larval populations in sheep show different results on the number of generations according to the local climate. Mean monthly larval profiles of L1 and L3 burdens of sheep from West African Sahelian countries, Mediterranean countries (Morocco, Tunisia and Sicily) and Southwest France were compared. Valuable information on the suspected exten- sion of the fly season is obtained showing the period of infection in each area. This knowledge will be a valuable tool to help in choosing the right treatment at the right period.
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Experimental infestation of goats with first instar larvae of Oestrus Ovis
Veterinary Research, 1996Co-Authors: C. Duranton, J.p. Bergeaud, P. DorchiesAbstract:: A protocol of experimental infection with Oestrus Ovis larvae L1 was applied to kids in order to study their susceptibility to Oestrus Ovis. Two-month-old kids, born and raised indoors during winter, were infected with single or repeated administrations of Oestrus Ovis L1. Two or three months later, the kids were slaughtered and larvae harvested from their nasal cavities. Following a single administration of 30 L1, 8.3 and 3.3% of the larvae survived after two and three months respectively. After eight repetitive infections in two months with the same number of larvae (30 L1), only 2.2% survived. Over a three months period, ie, eleven repetitive infections with a total of 61 L1, only 1.4% were found at the necropsies. This experiment indicates that goats are not very susceptible to Oestrus Ovis infection.
Ph Dorchies - One of the best experts on this subject based on the ideXlab platform.
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specific igg antibody responses in Oestrus Ovis l diptera oestridae infected sheep associations with intensity of infection and larval development
Veterinary Parasitology, 2008Co-Authors: C E Angulovaladez, J.p. Bergeaud, F Prevot, C Grisez, Felipe Ascencio, A Scala, A Carta, R Cepedapalacios, Getachew Terefe, Ph DorchiesAbstract:Larvae of Oestrus Ovis (Diptera: Oestridae) are ubiquitous parasites of nasal and sinusal cavities of sheep and goats. According to the chronobiology of O. Ovis infections in Sardinia and the seasonal pattern of the IgG response, the optimal period to investigate the relationships between O. Ovis larval populations and intensity of local and systemic IgG antibody responses was mid-July in the
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pathophysiology of Oestrus Ovis infection in sheep and goats a review
Veterinary Record, 1998Co-Authors: Ph Dorchies, C. Duranton, Philippe JacquietAbstract:Oestrus Ovis is a very common parasite of sheep and goats in many countries. Its pathological effects are often underestimated because owners and veterinarians are used to seeing the infection. The study of natural and experimental infections has provided information about the evolution of the disease and its pathophysiology. Hypersensitivity is involved; the numbers of mast cells and eosinophils increase but changes in IgE have only recently been examined. Little is known about the development of immunity but it is possible that some animals are immunodeficient.
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epidemiology of Oestrus Ovis in southwest france
Veterinary Parasitology, 1991Co-Authors: J M Yilma, Ph DorchiesAbstract:Abstract From July 1989 to June 1990, 555 heads of adult sheep obtained from Pamiers slaughterhouse (southwest France) were examined for infestation by Oestrus Ovis . Infestation was present in 65% of the heads and the mean larval burden per positive case over the year was 24.8. The monthly prevalence rate varied from 44% in April to 88.2% in November. There are usually three generations of Ovis each year: the first March–April, the second in June–July and the last in September–October. There was no fly activity in winter and during the hottest months of summer. On the other hand, nearly all the larvae overwintered as the firs stage. This study emphasizes the seriousness of the problem in the region and the authors recommend three strategic treatments per year during periods of high fly activity.
Guillaume Tabouret - One of the best experts on this subject based on the ideXlab platform.
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cellular and humoral local immune responses in sheep experimentally infected with Oestrus Ovis diptera oestridae
Veterinary Research, 2003Co-Authors: Guillaume Tabouret, P. Dorchies, Caroline Lacroux, Olivier Andreoletti, Jean Paul Bergeaud, Yacob Hailutolosa, H Hoste, F Prevot, C Grisez, Philippe JacquietAbstract:Cellular and humoral local responses were investigated following repetitive artificial Oestrus Ovis infections in lambs. The presence of larvae induced a huge local recruitment of either leucocytes (T and B lymphocytes, macrophages) or granulocytes (eosinophils, mast cells and globule leucocytes). This cellular response was more pronounced in the ethmoid and sinus (development sites of second and third instar larvae) than in the septum or turbinates where first instar larvae migrate. Infected lambs produced Oestrus Ovis specific IgG and IgA antibodies in their mucus. This local humoral response was mainly directed against larval salivary gland antigens and not against larval digestive tract antigens. Compared to the control animals, the sinusal mucosa of infected animals was extremely thickened and the epithelium exhibited hyperplasia, metaplasia and eosinophilic exocytosis. The possible roles of these local immune responses in the regulation of O. Ovis larvae populations in sheep are discussed.
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Oestrus Ovis in sheep relative third instar populations risks of infection and parasitic control
Veterinary Research, 2001Co-Authors: Guillaume Tabouret, P Jacquiet, Philip J Scholl, P. DorchiesAbstract:Oestrus Ovis (L.) (Diptera: Oestridae), the nasal bot fly, has a relatively short free-living life cycle outside of the host, and therefore it is necessary to know when the parasitic period occurs in order to prevent the clinical signs and economic losses caused by this parasite. The length of this parasitic portion of the life cycle is quite variable: a few weeks to several months depending on the season and climatic conditions. Surveys of Oestrus Ovis larval populations in sheep show different results on the number of generations according to the local climate. Mean monthly larval profiles of L1 and L3 burdens of sheep from West African Sahelian countries, Mediterranean countries (Morocco, Tunisia and Sicily) and Southwest France were compared. Valuable information on the suspected exten- sion of the fly season is obtained showing the period of infection in each area. This knowledge will be a valuable tool to help in choosing the right treatment at the right period.
F Prevot - One of the best experts on this subject based on the ideXlab platform.
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specific igg antibody responses in Oestrus Ovis l diptera oestridae infected sheep associations with intensity of infection and larval development
Veterinary Parasitology, 2008Co-Authors: C E Angulovaladez, J.p. Bergeaud, F Prevot, C Grisez, Felipe Ascencio, A Scala, A Carta, R Cepedapalacios, Getachew Terefe, Ph DorchiesAbstract:Larvae of Oestrus Ovis (Diptera: Oestridae) are ubiquitous parasites of nasal and sinusal cavities of sheep and goats. According to the chronobiology of O. Ovis infections in Sardinia and the seasonal pattern of the IgG response, the optimal period to investigate the relationships between O. Ovis larval populations and intensity of local and systemic IgG antibody responses was mid-July in the
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cellular and humoral local immune responses in sheep experimentally infected with Oestrus Ovis diptera oestridae
Veterinary Research, 2003Co-Authors: Guillaume Tabouret, P. Dorchies, Caroline Lacroux, Olivier Andreoletti, Jean Paul Bergeaud, Yacob Hailutolosa, H Hoste, F Prevot, C Grisez, Philippe JacquietAbstract:Cellular and humoral local responses were investigated following repetitive artificial Oestrus Ovis infections in lambs. The presence of larvae induced a huge local recruitment of either leucocytes (T and B lymphocytes, macrophages) or granulocytes (eosinophils, mast cells and globule leucocytes). This cellular response was more pronounced in the ethmoid and sinus (development sites of second and third instar larvae) than in the septum or turbinates where first instar larvae migrate. Infected lambs produced Oestrus Ovis specific IgG and IgA antibodies in their mucus. This local humoral response was mainly directed against larval salivary gland antigens and not against larval digestive tract antigens. Compared to the control animals, the sinusal mucosa of infected animals was extremely thickened and the epithelium exhibited hyperplasia, metaplasia and eosinophilic exocytosis. The possible roles of these local immune responses in the regulation of O. Ovis larvae populations in sheep are discussed.
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seroprevalence of Oestrus Ovis infection in sheep in southwestern germany
Veterinary Parasitology, 2002Co-Authors: C Bauer, F Prevot, G Steng, P. DorchiesAbstract:The aim of the survey was to determine the seroprevalence of Oestrus Ovis infection in flocks in southwestern Germany. Serum samples collected from 1497 sheep (>6 months of age) of 110 flocks in 1997 and 1998 were examined for antibodies to crude somatic antigens of O. Ovis second-stage larvae using an ELISA test. Data on the farm management were obtained by a questionnaire. Overall, 76% of the flocks had at least one seropositive animal, and the seroprevalence of anti-Oestrus antibodies was 50% in sheep. Flock size was the only risk factor significantly associated with the detection of antibodies. Larger flocks (>50 ewes) were more likely to be seropositive than smaller ones. These results show that Oestrus infections are widespread in sheep in southwestern Germany. Further investigations are required to estimate the economic importance of oestrosis and the efficiency of control measures.
Abdullah Algarni - One of the best experts on this subject based on the ideXlab platform.
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conjunctival ophthalmomyiasis caused by the sheep nasal botfly Oestrus Ovis
American Journal of Ophthalmology, 1991Co-Authors: James A Cameron, Nader M Shoukrey, Abdullah AlgarniAbstract:Three patients had conjunctival ophthalmomyiasis caused by the ovine nasal botfly. All patients had a sudden onset of redness, tearing, and foreign-body sensation of the affected eye. One to nine Oestrus Ovis first-instar larvae were removed from the bulbar or palpebral conjunctiva of each patient. Symptoms and clinical signs resolved after mechanical removal of the larvae. Specific taxonomic diagnosis of O. Ovis larvae was determined on the basis of characteristic conformation of the terminal end of the larval caudal segment as seen by use of light microscopy.
