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See detailSerological and Biochemical Follow-up in Cattle Naturally Infected with Fasciola Hepatica, and Comparison with a Climate Model for Predicting Risks of Fasciolosis
Bossaert, K.; Lonneux, J. F.; Godeau, Jean-Marie ULg et al

in Veterinary Research (1999), 30(6, Nov-Dec), 615-28

Several biological parameters were measured in 31 heifers naturally infected with Fasciola hepatica during one grazing season in the Belgian Ardennes. A forecast model based on daily temperature used to ... [more ▼]

Several biological parameters were measured in 31 heifers naturally infected with Fasciola hepatica during one grazing season in the Belgian Ardennes. A forecast model based on daily temperature used to assess the risk of fasciolosis was fitted to this assay. Cattle were turned out to two pastures. Each pasture was divided into two plots: one was treated with calcium cyanamide and the other was left untreated. The Lymnaea truncatula snails were counted on three different occasions. The results indicated a poor molluscicide efficiency. Body weight gains, anti-Fasciola antibody levels, faecal egg counts, levels of sorbitol dehydrogenase (SDH) and gamma-glutamyl transferase (gamma GT), packed cell volumes, white blood cells and differential leucocyte counts were determined monthly. No statistically significant difference was observed between animals from the two plots regardless of the recorded data. No correlation was found between body weight gains and other biological data. The sampling date had a significant effect on the antibody responses within a same group, and on the enzymatic levels for all groups combined. The forecast results were consistent with the recorded data. Temperature was a major bioclimatic constraint on the transmission of life cycle, and risk of infection occurred mainly in late spring (May/June) and in early September. Current results might be used to issue advice on the need for flukicide treatment of cattle. The indicators of the infection considered alone were useless and it is concluded that herd diagnosis of fasciolosis may rely on the rise of specific antibody levels, possibly associated with an increase in hepatic enzyme activities. [less ▲]

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See detailThe effect of hydroxypropyl-b-cyclodextrins on the pharamacokinetics of albendazole in sheep
Evrard, Brigitte ULg; De Tullio, Pascal ULg; Chiap, Patrice ULg et al

in Proceedings of 26th International Symposium on Controlled Release of Bioactive Materials (1999)

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See detailPurification and Characterization of a 315 Kda Keratinolytic Subtilisin-Like Serine Protease from Microsporum Canis and Evidence of Its Secretion in Naturally Infected Cats
Mignon, Bernard ULg; Swinnen, M.; Bouchara, J. P. et al

in Medical Mycology (1998), 36(6), 395-404

A keratinolytic protease, secreted as the major component by a feline clinical isolate of Microsporum canis cultivated in a minimal medium containing cat keratin, was purified by affinity chromatography ... [more ▼]

A keratinolytic protease, secreted as the major component by a feline clinical isolate of Microsporum canis cultivated in a minimal medium containing cat keratin, was purified by affinity chromatography on bacitracin agarose and gel filtration. The apparent molecular mass of the enzyme was 31.5 kDa and the pI was 11.8. The enzyme was not glycosylated and its first 15 N-terminal amino acids showed numerous similarities with other fungal subtilisins. The optimum pH was around 9 while inactivation of the enzyme was reversible at pH 4, but not at pH 11. The enzyme was stable at 37 degrees C with an apparent optimum temperature around 55 degrees C. PMSF, soybean trypsin inhibitor (SBTI) and chymostatin strongly inhibited the proteinase. The highest affinity (Km of 0.37 mM) and physiological efficiency (k(cat)/Km) were obtained for the synthetic substrate N-Suc-Ala-Ala-Pro-Phe-p-nitroanilide. These results indicate that the keratinase belongs to the subtilisin-like serine protease family. Purified rabbit immunoglobulins G prepared against the keratinase and used in an immunohistochemical test allowed the detection of the keratinase produced by the fungus invading hair structures in naturally infected cats. The in vitro keratinolytic activity of the enzyme and its production in vivo suggest that it may contribute to pathogenicity. [less ▲]

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See detailUse of Excretory/Secretory Antigens in a Competition Test to Follow the Kinetics of Infection by Fasciola Hepatica in Cattle
Leclipteux, Thierry ULg; Torgerson, P. R.; Doherty, M. L. et al

in Veterinary Parasitology (1998), 77(2-3), 103-14

Eight 16-18-month-old Charolais heifers were experimentally infected with Fasciola hepatica. An antigen competition assay was used to follow the kinetics of the infection and was compared to antibody ... [more ▼]

Eight 16-18-month-old Charolais heifers were experimentally infected with Fasciola hepatica. An antigen competition assay was used to follow the kinetics of the infection and was compared to antibody tires and serum liver enzymes. The antigen competition assay was able to detect the presence of infection as soon as 6 days after the start of the experimental infection which is considerably sooner than other methods. Consequently, this assay would be useful in diagnosing fasciolosis early in the prepatent period. The animals were slaughtered at the end of the experiment, the livers recovered and post-mortem fluke burdens determined. However, only serum liver enzyme levels gave any indication of the intensity of infection in the different animals. [less ▲]

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See detailHumoral and Cell-Mediated Immune Responses of Beef and Dairy Cattle Experimentally Infested with Psoroptes Ovis
Lonneux, J. F.; Nguyen, T. Q.; Hollanders, W. et al

in American Journal of Veterinary Research (1998), 59(5), 583-7

OBJECTIVE: To compare cellular and humoral immune responses of beef (Belgian White and Blue [BWB]) and dairy (Friesian-Holstein [FH]) cattle to Psoroptes ovis infestation and to determine whether P ovis ... [more ▼]

OBJECTIVE: To compare cellular and humoral immune responses of beef (Belgian White and Blue [BWB]) and dairy (Friesian-Holstein [FH]) cattle to Psoroptes ovis infestation and to determine whether P ovis infestation impaired immune responses to infectious bovine rhinotracheitis virus (IBR) vaccine or an immunogenic protein (keyhole-limpet hemocyanin [KLH]). ANIMALS: 19 BWB and 6 FH 1-year-old calves. PROCEDURE: 2 trials were performed. In each trial, 7 (trial 1) or 6 (trial 2) BWB calves and 3 FH calves were experimentally infested with P ovis and 3 BWB calves were maintained as uninfested controls. Animals were inoculated with KLH and IBR virus vaccine twice; 3 BWB calves in each trial were treated with ivermectin. Serum antibody responses to KLH, IBR virus, and P ovis were measured by use of ELISA. A lymphocyte transformation assay was used to determine nonspecific responses to 3 mitogens and specific lymphocyte reactivity to P ovis antigen. RESULTS: In each trial, 3 BWB and 3 FH calves developed clinical signs of psoroptic mange and mites could be recovered. Infested and control animals developed similar antibody titers to KLH and IBR virus. Antibodies to P ovis were detected early in some infested calves, and this was correlated with a marked cell-mediated immune response. Lymphocyte responsiveness to the 3 mitogens was not significantly different among groups. CONCLUSIONS: In these calves, infestation with P ovis induced a marked humoral and cell-mediated immune response. Immunosuppression was not evident. [less ▲]

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See detailField Efficacy of Injectable Doramectin against Chorioptes Bovis in Naturally Infected Cattle
Losson, Bertrand ULg; Mignon, Bernard ULg; Bossaert, K. et al

in Veterinary Record : Journal of the British Veterinary Association (1998), 142(1), 18-19

A single subcutaneous injection of doramectin at a dose rate of 200 micrograms/kg bodyweight was effective in controlling an infection of Chorioptes bovis mites in naturally infected cattle. From 14 days ... [more ▼]

A single subcutaneous injection of doramectin at a dose rate of 200 micrograms/kg bodyweight was effective in controlling an infection of Chorioptes bovis mites in naturally infected cattle. From 14 days after treatment, the geometric mean number of live mites was significantly lower (P < 0.001) in the doramectin-treated cattle than in the control group at each sampling until day 35. The percentage efficacy (treated versus controls) of doramectin against C bovis at day 35 was 99.9 per cent and the percentage reduction (day 35 versus day 0) in the treated animals was 99.3 per cent. At day 35, all seven controls were still positive for C bovis whereas five of the eight doramectin-treated animals were free of live mites. [less ▲]

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See detailMéningo-encéphalite granulomateuse à Aspergillus sp. chez une chienne Airedale Terrier de un an
Poncelet, Luc; Belayat, F.; Losson, Bertrand ULg et al

in Annales de Médecine Vétérinaire (1998)

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See detailThe in vitro and in vivo production of a 31.5-kD keratinolytic subtilase from Microsporum canis and the clinical status in naturally infected cats.
Mignon, Bernard ULg; Nikkels, Arjen ULg; Pierard, Gérald ULg et al

in Dermatology : International Journal for Clinical & Investigative Dermatology (1998), 196(4), 438-441

BACKGROUND: Microsporum-canis-infected cats, especially the asymptomatic infected ones, are mainly responsible for the zoonotic disease. The important variability of the clinical signs in cats is poorly ... [more ▼]

BACKGROUND: Microsporum-canis-infected cats, especially the asymptomatic infected ones, are mainly responsible for the zoonotic disease. The important variability of the clinical signs in cats is poorly understood. Recently, a 31.5-kD keratinolytic subtilase was found to be a putative virulence factor. OBJECTIVE: To investigate the possible relationship between the clinical status of dermatophytic cats and the production of the keratinase. METHODS: Seven M. canis strains isolated either from clinically affected, asymptomatic infected or mechanical carrier cats were tested for the in vitro production of the enzyme. The immunohistochemical detection of the enzyme was also assessed in skin biopsies of 4 symptomatic and 7 asymptomatic naturally infected cats. RESULTS: All the strains produced in vitro a 31.5-kD keratinolytic subtilase. The enzyme was present in all but 1 of the infected cats. CONCLUSION: The production of the keratinase is not a factor directly responsible for the clinical picture seen in M.-canis-infected cats. [less ▲]

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See detailLes tiques et leur rôle vectoriel
Losson, Bertrand ULg; Mignon, Bernard ULg

in Pharmasphère (1998), 25

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See detailEléments du diagnostic des parasitoses externes des ruminants
Lonneux, J. F.; Losson, Bertrand ULg

in Point Vétérinaire (1998), 188

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See detailInteractions entre le vecteur et le trypanosome dans la détermination de la compétence vectorielle des glossines
Kazadi, J. M.; Geerts, S.; Kagéruka, P. et al

in Revue d'Elévage et de Médecine Vétérinaire des Pays Tropicaux (1998), 51

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See detailCompétence vectorielle des lignées Bobo Dioulasso et Maisons-Alfort de Glossina palpalis gambiensis Vanderplank 1949 infectées simultanément par Trypanosoma brucei brucei EATRO 1125
Kazadi, J. M.; Kagéruka, P.; Losson, Bertrand ULg et al

in Revue d'Elévage et de Médecine Vétérinaire des Pays Tropicaux (1998), 51

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See detailResearch on epizootology and prevention of hypodermiasis in cattle in Transylvania, Romania
Cozma, V.; Suteu, I.; Losson, Bertrand ULg et al

in Buletinul Universitatii de Stiinte Agricole si Medicina Veterinara Cluj-Napoca (1998), 52

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