P Dorchies

École Nationale Vétérinaire de Toulouse, Tolosa de Llenguadoc, Midi-Pyrénées, France

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Publications (65)134.49 Total impact

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    ABSTRACT: 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). Firstly, 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 200 mg/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 (55 d).
    Veterinary Parasitology 01/2013; · 2.38 Impact Factor
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    ABSTRACT: Oestrus ovis L. (Diptera: Oestridae) is a cosmopolitan agent of myiasis in sheep and goats. The parasitic phase begins after adult females deposit first-stage larvae (L1) into the nostrils of hosts; these larvae develop into L2 and L3 in the nasal and sinus horn cavities. Sneezing and nasal discharges are the major clinical signs in infected animals. The pathogenesis of O. ovis infection is caused by: (a) the trauma resulting from the mechanical action of spines and hooks during larval movement on mucosal membranes, and, more importantly, (b) an allergenic reaction provoked by molecules excreted/secreted by larvae, of which salivary antigens are those mainly recognized by the host's immune system. The recruitment of immune reactive cells increases gradually from the nasal to sinus cavities in infected hosts. Mast cells, eosinophils, macrophages and lymphocytes are always more numerous in infected than non-infected animals. Humoral (antibody) systemic response of immunoglobulin G (IgG) usually reaches seroconversion 2-4 weeks post-first infection and the highest levels are observed during the development of L2 and L3 larvae. Local antibody responses include specific IgG, which has been found to negatively correlate with larval survival and development. Hypersensitivity reaction, immunomodulation, immunization trials and mixed infections of O. ovis and helminths are discussed.
    Medical and Veterinary Entomology 09/2010; 25(2):117-25. · 2.21 Impact Factor
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    ABSTRACT: A comparative experimental study was performed between Barbados Black Belly (resistant) and INRA-401 (susceptible) breeds of sheep in which primary infection with Haemonchus contortus was terminated on day 16. Measurements of parasite burden, abomasal tissue eosinophilia, IL-4, IL-5 and IL-13 mRNA transcripts in abomasal mucosa, and in vitro larval killing abilities of blood eosinophils were performed. The results show that: (1) worm burden was significantly lower and blood eosinophilia higher in the Black Belly than in the INRA breed. (2) Abomasal cytokine expression was noticed but no difference existed between the two breeds. (3) Three out of four Black Belly sheep had higher tissue eosinophil numbers compared to the INRA sheep (more eosinophils observed in the pyloric than in the fundic region in both breeds). (4) No significant difference was observed in the in vitro larval immobilizing potential of eosinophils between the two breeds. Collectively, abomasal eosinophil number and larval killing abilities of blood eosinophils do not seem to explain the difference in worm burden between the two breeds.
    Veterinary Parasitology 08/2009; 165(1-2):161-4. · 2.38 Impact Factor
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    ABSTRACT: The aims of this study were to analyze the systemic IgG responses against third-instar salivary gland (L3SG) antigens by ELISA in Oestrus ovis experimentally infected kids (EIK) and in naturally exposed adult goats (NEG). Firstly, kids (n=4 per group) were assigned to receive intranasally 0, 12, 24, 36, and 48 first-instars in experimental infections. Blood samples were taken from EIK at Days 0, 14, 42 and 67 post-infection. At necropsy (Day 67), larval number and developmental instars were recorded. In an epidemiological study, blood serum samples were collected from 448 grazing NEG (n=20 flocks) in Baja California Sur, Mexico. Results showed that larval establishment rate was similar in EIK groups. Systemic IgG response reached the threshold after Day 42, but humoral response was not statistically different among EIK groups receiving experimental infections. In NEG, all surveyed flocks (100%) showed specific systemic IgG antibodies to L3SG antigens and the overall goat oestrosis prevalence was 59.2%. In conclusion, larval L3SG antigens were effective in detection of specific systemic IgG antibodies against O. ovis infected kids and goats by ELISA.
    Veterinary Parasitology 03/2009; 161(3-4):356-9. · 2.38 Impact Factor
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    ABSTRACT: 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 summer season. Sarda x Lacaune ewes (n=186), divided into three ram-families were used in the study. Systemic and local IgG responses were measured by ELISA tests using second stage larval crude extracts (L2CE) and L2 (L2SGC) and L3 (L3SGC) salivary gland contents as coating antigens. The number of larval instars, larval length of L1, L2 and L3 larvae, and larval weight of L2 and L3 larvae were individually recorded after ewe necropsy. Negative correlations among larval establishment and/or larval development on the one hand and intensity of local or systemic IgG responses on the other hand were found in two out of three studied ram-families.
    Veterinary Parasitology 09/2008; 155(3-4):257-63. · 2.38 Impact Factor
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    ABSTRACT: Thelazia callipaeda (Spirurida, Thelaziidae) is a small nematode living in the conjunctival sac of domestic and wild carnivores, rabbits and humans causing lacrimation, epiphora, conjunctivitis, keratitis and even corneal ulcers. The first autochthonous cases of thelaziosis affecting four dogs and one cat living in South Western France (Dordogne area) are reported and described. Nematodes recovered from the animals were morphologically identified as T. callipaeda and a partial region of the cytochrome oxidase c subunit 1 gene (cox1) was amplified by PCR from nematode specimens (from two dogs and the cat). In each case, this was shown to have an identical sequence to the haplotype 1 (h1) of T. callipaeda. So far, the arthropod acting as intermediate host of T. callipaeda eyeworms has not been identified in France although it might be Phortica variegata (Steganinae, Drosophilidae) as recently described in Italy.
    Veterinary Parasitology 12/2007; 149(3-4):294-7. · 2.38 Impact Factor
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    ABSTRACT: This study identified and characterized hydrolytic enzymes in salivary gland products of Oestrus ovis larvae. Third instars were collected from the heads of slaughtered goats. Salivary glands were extracted, their products obtained by centrifugation and the enzymatic profile determined. Optimum pH, temperature of maximum proteolytic activity, thermal stability, and resistance of salivary gland products were determined on collagen and subclasses of proteases were identified using protease inhibitors. Zymograms were used to determine the molecular weight of proteases. Antigenic protein bands were revealed by immunoblotting using sera obtained from experimentally infested goats. Seven positive enzymatic activities were detected in salivary gland products: acid phosphatase, naphthol-AS-BI-phosphohydrolase, esterase (C4), esterase lipase (C8), leucine arylamidase, alpha-glucosidase and N-acetyl-beta-glucosaminidase. Optimum pH for proteolytic activity was 8.0; proteolytic activity increased with temperature (10-50 degrees C) then drastically decreased at 60 degrees C. Proteases in O. ovis salivary gland products belong to the serine subclass. In Zymograms, bands of proteolytic activity were detected in the 20-63 kDa range; the immunoblot showed three antigenic bands, one of them related to a protease band (63 kDa). Serine proteases in O. ovis salivary gland products are most likely involved in larval nutrition and host immuno-modulation.
    Veterinary Parasitology 11/2007; 149(1-2):117-25. · 2.38 Impact Factor
  • C Thomas, P Jacquiet, P Dorchies
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    ABSTRACT: The heat wave of 2003 summer had serious consequences on helminths prevalence and epidemiology. Comparison of 1917 cattle epg counts in southwestern France for years before and after showed that prevalence and mean numbers of Fasciola hepatica, paramphistomids, Dicroccelium lanceolatum and gastrointestinal strongyles eggs were significantly reduced. Nevertheless, the next year the epg counts were quickly increasing. Several factors may have induced a more or less long modification: strains of helminths may become adapted, a new spreading of intermediate hosts may occur with a modified ecology and finally moving of hosts and reservoirs may be amongst causes of epidemiological changes. Finally, after a heat wave the anthelmintic pressure may be maintained, as parasites seem quickly become adapted to a novel and modified environment.
    Parasite 10/2007; 14(3):265-8. · 0.82 Impact Factor
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    ABSTRACT: The immune responses to Haemonchus contortus were compared in studies in resistant Barbados Black Belly (BBB) and susceptible INRA 401 (INRA) breeds of lambs. The cytokine patterns indicated a Th2-biased response in both breeds. A more persistent and elevated Th2 cytokine mRNA transcription and blood eosinophilia were noted in the BBB lambs. However, at days 4 and 30 post-infection, abomasal recruitment of eosinophils and mast cells were similar between the two breeds. Following primary infections, the BBB demonstrated a substantially lower faecal egg count compared to the INRA lambs. Furthermore, worm counts at 4 and 30 days post-infection, and adult female worm size and in utero egg counts 30 days after the first infection were significantly lower in the BBB than in the INRA breed. In the INRA breed, re-infection caused a significant reduction in most parasitological parameters compared with those observed after the primary infection. A similar response was not observed in the BBB sheep. In conclusion, while the major driving force in the response to H. contortus infection is a Th2-biased immunity in which the BBB showed its maximal performance during the primary infection, the INRA breed performed better after re-infection compared to its response to first exposure.
    Parasite Immunology 09/2007; 29(8):415-24. · 2.21 Impact Factor
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    ABSTRACT: The study was conducted to determine the prevalence and risk factors of toxoplasmosis in goats in Southern and central Ethiopia between October 2005 and May 2006. A total of 641 goats sera were tested using Modified Direct Agglutination Test (MAT), of which 480 (74.8% CI: 71.3, 78.2) were found to be positive. The highest prevalence was recorded in South Omo zone (82%) while the lowest was observed in East Shewa zone (62.2%). The study revealed that goats raised in southern Ethiopia are at a greater risk of acquiring T. gondii infection (OR = 2.55, CI: 1.726, 3.776; p = 0.000) than those which are raised in central Ethiopia. The prevalence of anti T. gondii antibody was significantly higher in older goats than in kids (OR = 2.33, CI: 1.490, 3.655; p < 0.0002) and in females than in males (p < 0.0007; OR = 0.68, CI: 0.542, 0.849). No significant difference was observed among goats kept under various husbandry practices. The high prevalence of toxoplasmosis in Ethiopian goats suggests a high risk of human infections. Further epidemiological investigation, isolation and genotyping of T. gondii are planned.
    Parasite 07/2007; 14(2):155-9. · 0.82 Impact Factor
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    T Getachew, P Dorchies, P Jacquiet
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    ABSTRACT: Haemonchosis, with its very wide distribution, has become a very important production constraint in sheep farms in tropical, subtropical and temperate regions worldwide. Various intrinsic and extrinsic factors determine the survival of Haemonchus contortus and hence the development of the disease in the animal. In general, control of gastrointestinal nematode infestation in sheep relies heavily on anthelmintic treatments. However, the indiscriminate use of these drugs has led to the widespread emergence of drug resistant strains of parasites, that has necessitated the development and use of various parasite control methods such as grazing management, biological agents and vaccines and the selection of resistant breeds of animals, with or without moderate use of anthelmintics. The ultimate goal of such control programs is to enhance productivity, while minimising risks regarding drug resistance and consumer and environmental concerns. This review attempts to highlight the different methods employed in the control of haemonchosis in sheep and the practical limitations associated with both control programs and the internal and external factors associated with the parasite and its microenvironment.
    Parasite 04/2007; 14(1):3-14. · 0.82 Impact Factor
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    ABSTRACT: Larval midgut proteins of hematophagous parasites contain strong antigens that can be used for host immunization. This concept has been applied for immunization of Pelibuey sheep against Oestrus ovis L. (Diptera: Oestridae). The aim of this study was to examine the effect of immunization on larval establishment (LE) and development. Immunized lambs (I, n = 6) received two injections of crude gut membrane protein extracts (GMPE) from third instar larvae with Freund's incomplete adjuvant (FIA) on days 0 (Day of first immunization) and 21 (0.4 and 0.45 mg GMPE/lamb, respectively). The control group (C, n = 5) received physiological saline with FIA. Lambs were challenged with first instars on Day 29 (20 larvae) and Day 43 (25 larvae). Blood samples were collected biweekly and IgG titers were analyzed by ELISA. All lambs were slaughtered on Day 90 and number of larvae recovered, larval stage and larval weight were recorded at necropsy. No significant effect of immunization on LE (C = 28.9%; I = 31.0% P > 0.05) was observed. Antibody titers were higher in the immunized group on Day 28 (P < 0.05), but subsequently similar in both groups. Larval physiological age and weight were also significantly (P < 0.05) affected by immunization. Immunization of Pelibuey lambs with GMPE did not affect LE but did delay O. ovis larval development.
    Veterinary Parasitology 02/2007; 143(2):140-6. · 2.38 Impact Factor
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    ABSTRACT: Mast cells and eosinophils are known to participate in the processes of al-lergic inflammation and gastrointestinal parasitic diseases. Sodium cromo-glycate (SCG), a non steroid anti-allergic drug is used in the prophylaxis and treatment of asthma and GIT allergic disorders in human. This experimental study has used SCG to reduce the population and degranulation of mast cells and the subsequent mobilisation of eosinophils during Haemonchus contor-tus infection, in an attempt to rendering the relatively nematode resistant Black Belly breed of sheep more prone to the infection. Animals were divi-ded in to three groups of 5 sheep (groups SH, H and C: SCG treated and in-fected, non-treated and infected and negative control respectively). Blood and bone marrow eosinophil counts, faecal egg count (FEC), tissue eosino-phil, mast cell and globule leukocyte counts as well as measurement of other parasitological parameters were performed. Oral administration of SCG for 5 consecutive weeks successfully reduced the level of blood and bone mar-row eosinophil number but not tissue eosinophil level. Furthermore, a signi-ficant reduction in mast cells, and a moderate reduction in globule leucocyte numbers were observed in the abomasal mucosa. Mean values for FEC and worm counts were higher in group SH. However, there was no significant difference between SCG-treated and non-treated group, which suggests the reduction in the inflammatory response alone, may not be sufficient enough to influence H. contortus development in sheep. As the dose and mode of administration of this drug is not fully established for sheep, further studies might be required to make SCG a useful tool for experimental studies during gastrointestinal parasitism. RÉSUMÉ Un traitement quotidien au cromoglycate de sodium diminue les ré-ponses mastocytaires et éosinophiliques sanguines chez des moutons de race Black Belly résistants à Haemonchus contortus . Mastocytes et éosinophiles sont des cellules impliquées dans les proces-sus allergiques et les maladies parasitaires du tube digestif. Le cromoglycate de sodium (CGS), une drogue non stéroïdienne, est utilisée dans la préven-tion et le traitement de l'asthme bronchique et des manifestations allergiques du tube digestif. Cette expérimentation a utilisé le CGS afin de réduire la po-pulation et la dégranulation des mastocytes muqueux mais également la mo-bilisation des éosinophiles durant une infestation par Haemonchus contortus chez des moutons de race Barbados Black Belly réputés résistants à ce para-site. 15 agneaux de cette race ont été répartis en trois groupes de 5 animaux : i) traités au CGS et infestés par H. contortus (SH), ii) non traités au CGS et infestés (H) et iii) témoins non traités et non infestés (C). Des comptages ré-guliers d'éosinophiles sanguins ont été réalisés de même que des comptages d'oeufs dans les matières fécales. Après l'autopsie, 30 jours après l'infesta-tion, une évaluation de la proportion d'éosinophiles dans la moelle osseuse, du nombre d'éosinophiles, de mastocytes et de leucocytes dans la muqueuse abomasale a été menée sur tous les animaux. L'administration quotidienne de CGS avant l'infestation puis durant toute la durée de l'infestation a réduit significativement l'éosinophilie sanguine et la proportion d'éosinophiles dans la moelle osseuse mais n'a pas eu d'effet sur le recrutement de ce type cellulaire dans la muqueuse abomasale. Une réduction significative du nom-bre de mastocytes et, dans une moindre mesure, de leucocytes est constatée chez les animaux du groupe SH. La diminution de réponse cellulaire dans ce dernier groupe ne s'est pourtant pas traduite par une installation significati-vement supérieure, un meilleur développement ou une plus grande fécondité des vers femelles même si des tendances apparaissent dans ce sens. Comme la posologie et le rythme d'administration du CGS ne sont pas complètement validés chez le mouton, d'autres expérimentations sont nécessaires pour fai-re du CGS un outil d'étude de la réponse cellulaire des ovins aux strongylo-ses gastro-intestinales.
    01/2007; 158(02):82-85.
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    ABSTRACT: Oestrosis is a nasal myiasis of sheep and goats caused by larvae of the fly Oestrus ovis and can lead to severe clinical signs, which together with the disturbance caused by the adult fly may result into serious economic losses. Infection rates and larval burdens are always higher in sheep than in goats after either natural or artificial infestation. The aim of this study was to compare the host preference of the adult fly O. ovis between sheep and goats in mixed flocks, where they are kept together under the same husbandry conditions and hence, are very similarly exposed to the fly preference. Blood sera samples were collected from a total of 397 sheep and 335 goats, from 43 mixed flocks located at different regions of Greece. Antibodies specific to O. ovis IgG were measured by ELISA. A flock was considered positive when at least one individual was positive, i.e. showed a seropositivity of >or=20% in relation to positive control sera. A total of 193 (48.6%) sheep and 58 (17.9%) goats were found to be seropositive against O. ovis. Thirty-eight (88.4%) out of 43 flocks had at least one seropositive animal. The mean seroconversion against O. ovis in animals from the different flocks was 38.6% and 13.6% for sheep and goats, respectively, whereas the variance of infection within each flock was 0-100%. The mean seropositivity between sheep that were found to be positive or negative was 60.6% and 5.4%, respectively, whereas the corresponding values between goats were 35.2% and 5.2%, respectively. No significant difference in the seroconversion values was noted between flocks from the different areas (P=0.817), whereas a very significant difference was observed between animal species (P=0.001). However, there was no significant difference when seroconversion comparisons were made within samples of the same animals species, sheep or goats from different flocks of all the regions included in the study (P=0.695). The results of this study clearly demonstrate that O. ovis has a widespread distribution in Greece, and the seroprevalence is significantly higher in sheep than goats (P=0.001).
    Veterinary Parasitology 06/2006; 138(3-4):382-5. · 2.38 Impact Factor
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    ABSTRACT: The purpose of this experiment was to determine if an earlier infection with Oestrus ovis would down regulate an infection with Trichostrongylus colubriformis when the larvae of O. ovis were expelled from the nasal cavities of sheep by a specific treatment. Three groups of five lambs were used: group 1 was artificially infected with O. ovis larvae and later with T. colubriformis, group 2 received O. ovis larvae and later was treated with ivermectin 14 days before being infected with T. colubriformis. Group 3 was infected with T. colubriformis only. The criteria examined were: the effects on nematode egg excretion, worm fecundity, nematode burdens and the kinetics of blood eosinophils. Significant decreases of nematode egg excretion, worm fecundity, nematode burdens were observed in group 1 compared to group 3. However, no changes were observed in either group 2 or 3. In group 2 it was noted that antiparasitic treatment induced a rapid decrease in blood eosinophils to a range close to the non-infected control group and this was associated with the removal of the down regulation effects of nematode burdens. This experiment showed that there is no cross immunity between O. ovis and T. colubriformis and that eosinophils may act against any parasite without specific priming.
    Veterinary Parasitology 05/2006; 137(1-2):184-8. · 2.38 Impact Factor
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    ABSTRACT: Resistance to anthelmintics in populations of gastrointestinal nematodes is a major concern in small ruminants. One solution to limit the spread of anthelmintic resistance is to apply treatments selectively by targeting the most susceptible animals within a flock. In dairy goats, previous studies have shown that, within a flock, goats in first lactation and those with high level of milk production were highly receptive to nematode infections. These results provided the rationale for targeted treatments. In dairy ewes, such epidemiological information on possible factors modulating the susceptibility to parasitism were still lacking. The objective of the current study was therefore to examine differences in the level of parasite infection and in the pathophysiological consequences in dairy ewes, depending on the age or on the level of milk production. In three farms, parasite egg excretion, and the serum concentrations of pepsinogen and inorganic phosphate were compared on one hand between primiparous and multiparous ewes; on the other hand, between ewes with the highest and the lowest level of milk production, within a cohort of 3–5-year old animals. Overall, the results did not indicate significant differences for both either the parasitological or pathophysiological measurements depending on the level of milk production. In contrast, significant differences were found according to age, indicating higher levels of infections in the primiparous ewes than in the multiparous ones and suggesting that this category of animals represents a particular parasitic risk within a flock.
    01/2006;
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    V Paolini, F Prevot, Ph Dorchies, H Hoste
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    ABSTRACT: The effects of tannins on adult populations of Haemonchus contortus, Trichostrongylus colubriformis and Teladorsagia circumcincta in goats are characterised mainly by a decrease in egg excretion without any significant changes in worm number. In contrast, the impact of tannins on T. colubriformis or T. circumcincta third-stage larvae (L3) is associated with a significant reduction in worm establishment. The objective of the present study was to examine the effects of quebracho extract tannins on H. contortus L3. The consequences of consumption of sainfoin hay were also examined. Twenty-one naïve kids were divided into three experimental groups. Group Q received quebracho extract and group S received sainfoin hay from days D3 to D5. Group C remained as an infected control group. All kids received 1500 L3 H. contortus on D0, D1 and D2. On D18, post-infection, the kids were slaughtered and the worm populations compared in the different groups. Compared to the control values, the worm counts decreased, respectively, by 33% and 38% in groups Q and S but the differences were not significant. No differences were found in pathophysiological measurements between the three groups. The results confirm differences in tannin effect according to nematode species but not parasitic stage.
    The Veterinary Journal 10/2005; 170(2):260-3. · 2.42 Impact Factor
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    ABSTRACT: Mixed parasitic infection of animals is a common phenomenon in nature. The existence of one species often positively or negatively influences the survival of the other. Our experimental study was started with the objectives to demonstrate the interaction of Haemonchus contortus and Oestrus ovis in relation to cellular and humoral immune responses in sheep. Twenty-two sheep of Tarasconnais breed (France) were divided into four groups (O, OH, H and C) of five or six animals. Group O and OH received 5 weekly consecutive inoculations with O. ovis L1 larvae (total = 82 L1) in the first phase of the experiment between days 0 and 28. On the second phase, groups OH and H received 5000 L3 of H. contortus on day 48 while group C served as our control throughout the experimental period. Parasitological, haematological, serological and histopathological examinations were made according to standard procedures and all animals were slaughtered at day 95. There was no significant variation in the number and degree of development of O. ovis larvae between the two infected groups. Furthermore, in tissues examined in the upper respiratory tract (nasal septum, turbinate, ethmoide and sinus), group O and OH has responded similarly on the basis of cellular inflammatory responses (blood and tissue eosinophils, mast cells and globule leucocytes (GL)) and serum antibody responses against the nasal bots. This may indicate that the presence of H. contortus in the abomasa of group OH had no marked influence over the development of O. ovis larvae in the upper respiratory tract. On the other hand, we have observed a significantly lower H. contortus female worm length, fecal egg count (FEC) and in utero egg count in animals harbouring the nasal bot (OH) than in the mono-infected group (H). This was significantly associated with higher blood eosinophilia, higher packed cell volume (PCV) and increased number of tissue eosinophils and globule leucocytes. We conclude that, the establishment of O. ovis larvae in the upper respiratory tract has initiated higher inflammatory cellular activity in group OH there by influencing the development and fecundity of H. contortus in the abomasum.
    Veterinary Parasitology 04/2005; 128(3-4):271-83. · 2.38 Impact Factor
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    ABSTRACT: Due to the high prevalence of anthelmintic resistance in goats, the need to explore novel approaches to control nematodes and to reduce the exclusive reliance on chemotherapy is strongly demanded in this host species. In sheep, several studies have shown that the consumption of tannin-rich legume forages was associated with positive effects on host resilience and resistance to parasite infection. In goats, studies on such interactions between tanniferous plants and nematode infections remain few. The objectives of the current study were to examine under natural conditions the effects of consumption of sainfoin hay by goats on the parasite populations and on host resilience. Eighteen adult cull goats naturally infected with Haemonchus contortus, Teladorsagia circumcincta and Trichostrongylus colubriformis were used in the study. At the start of the assay, the goats were allocated into two groups, balanced according to weight and the levels of egg excretion. The two groups grazed separate pastures for 3 months with similar stocking rates. Goats from group S received each month indoors, for 7 days, sainfoin hay and control goats (group C) received hay of ryegrass. The diets in both groups were made isoenergetic and isoproteic and the refusals measured. Individual parasitological and pathophysiological measurements were performed fortnightly in order to compare host resistance and resilience. At the end of the study, five goats per group were necropsied. The distribution of sainfoin was associated with: (1) a higher consumption of hay; (2) significant, lower levels of nematode egg excretion which was associated with a decrease in worm fertility but no change in worm population; however, the number of intestinal worms was reduced by 50% in group S; (3) a better host resilience. In particular, after 2 months of grazing, two control goats died and half of the remaining animals needed to be treated whereas this was not the case in group S. These differences were related to significant changes in pepsinogen and phosphate values (PCV) but not in pepsinogen and phosphate concentrations. These results demonstrate that a repeated distribution of sainfoin hay to grazing goats might be beneficial in regard of pasture contamination and host resilience. They suggest that administration of sainfoin hay might represent a valuable alternative and adjunct to reduce nematode infections in dairy goat flock.
    Veterinary Parasitology 03/2005; 127(3-4):277-83. · 2.38 Impact Factor
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    ABSTRACT: Twelve lambs were divided into two groups: Group C control, non-infected, and Group O infected once a week for 5 weeks with OEstrus ovis L1 through the same nostril. The first objective of this experiment was to check whether larvae moving through a given nostril remain in the same side nasal cavity or might to spread in both nasal cavities. It has been observed that larvae invade and spread through the entire nasal cavities. The only possible passage way between both sides is via the choanae and velum palatinum. The second objective was to follow the kinetics of blood eosinophilia. A primary peak in eosinophil numbers was noted 4 days following infection, with a higher peak following the second infection. After that, no major changes were seen. Nevertheless, the numbers of eosinophils were always higher than in control animals until the end of the follow-up. The third objective of the study was an enumeration of reactive cells (mast cells, globule leucocytes, and eosinophils) in the mucosae of the upper and lower respiratory tract after necropsy of the animals of the two groups. As observed in previous experiments, there was a large accumulation of these cells in mucosae of the upper respiratory tract. It was also worth noting a significant accumulation of eosinophils in the tissues of the trachea, bronchae and lungs even though OE. ovis was not present there. This "distant" eosinophilic reaction may have important consequences on patho-physiology of other parasites living in these locations: eosinophils have the potential to kill them even though these cells are not activated by their specific antigens.
    Veterinary Parasitology 01/2005; 126(3):339-47. · 2.38 Impact Factor

Publication Stats

770 Citations
134.49 Total Impact Points

Institutions

  • 1979–2013
    • École Nationale Vétérinaire de Toulouse
      • Laboratoire de parasitologie
      Tolosa de Llenguadoc, Midi-Pyrénées, France
  • 2002–2009
    • Addis Ababa University
      • School of Veterinary Medicine
      Addis Ababa, Adis Abeba Astedader, Ethiopia
    • Justus-Liebig-Universität Gießen
      • Institut für Parasitologie
      Gießen, Hesse, Germany
  • 2008
    • Centro de Investigaciones Biológicas del Noroeste
      La Paz, Baja California Sur, Mexico
  • 2006
    • Aristotle University of Thessaloniki
      • Faculty of Veterinary Medicine
      Thessaloníki, Kentriki Makedonia, Greece
  • 2000
    • Istituto Zooprofilattico Sperimentale della Sicilia
      Palermo, Sicily, Italy
  • 1999–2000
    • Autonomous University of Baja California Sur
      • Departamento de Zootecnia
      La Paz, Baja California Sur, Mexico