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See detailCulicoides trapping with Rothamsted suction traps before and during the bluetongue epidemic of 2006 in Belgium.
Fassotte, C.; Delecolle, J. C.; Cors, R. et al

in Preventive Veterinary Medicine (2008), 87(1-2), 74-83

The collection of biting midges was taking place some months before the first bluetongue outbreak in Belgium in August 2006. The Walloon Agricultural Research Centre had been monitoring aphid populations ... [more ▼]

The collection of biting midges was taking place some months before the first bluetongue outbreak in Belgium in August 2006. The Walloon Agricultural Research Centre had been monitoring aphid populations at two sites annually in Belgium (Gembloux and Libramont), using two stationary '12-m' Rothamsted suction traps. For the Gembloux trap, collections of insects captured daily from 11 May 2006 onwards were already available at the time of the outbreak. An examination of these samples revealed the presence of Culicoides, some species of which are considered as potential vectors of the bluetongue virus (BTV). The trapping was therefore extended beyond the normal aphid activity period and the Culicoides captured were identified to species level. From 11 May to 31 December 2006, the Gembloux trap caught 664 Culicoides specimens belonging to 19 species comprising known BTV-vectors. The second trap, at Libramont, was reactivated from 12 September to 13 October and caught 97 specimens belonging to nine species, all of which had been found at the Gembloux site. Among the 19 species identified, four were new to Belgian fauna: Culicoides achrayi, C. deltus, C. lupicaris and C. newsteadi. This paper examines the overall phenology and the physiological status of Culicoides in 2006 before and during the bluetongue epidemic. It discusses the potential of the Rothamsted suction trap to monitor Culicoides. [less ▲]

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See detailDetection of Neospora caninum in dog organs using real time PCR systems.
Ghalmi, F.; Losson, Bertrand ULg; Daube, Georges ULg et al

in Veterinary Parasitology (2008), 155

Neospora caninum is a parasite responsible for paresis in dogs. The dog can harbour enkysted parasites in several organs. The detection of N. caninum was performed using 3 different real time PCR systems ... [more ▼]

Neospora caninum is a parasite responsible for paresis in dogs. The dog can harbour enkysted parasites in several organs. The detection of N. caninum was performed using 3 different real time PCR systems all amplifying the NC5 DNA region. One system was based on Sybr1green, one on PlexorTM technology and the last on Taqman1 probe. Comparison of the three methods indicated that the detection limit was 1 equivalent genome on pure DNA but that this detection limit increased in the presence of foreign DNA using the Sybrgreen and Plexor systems. Therefore, the Taqman system was chosen to detect N. caninum in liver and spleen of naturally infected dogs. The overall prevalence was 32.2%. Comparison between PCR results and serological results using IFAT showed that among the 28 PCR positive dogs only 9 were seropositive and that 8 seropositive dogs were PCR negative. Therefore serology can underestimate the real carriage in dogs. However, PCR methods must be improved in terms of sensitivity and inhibition problems. [less ▲]

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See detailSecreted dipeptidyl peptidases as potential virulence factors for Microsporum canis.
Vermout, Sandy; Baldo, Aline ULg; Tabart, Jeremy et al

in FEMS Immunology & Medical Microbiology (2008), 54(3), 299-308

Dermatophytoses caused by Microsporum canis are frequently encountered in cats and dogs; they are highly contagious and readily transmissible to humans. In this study, two single genes, respectively ... [more ▼]

Dermatophytoses caused by Microsporum canis are frequently encountered in cats and dogs; they are highly contagious and readily transmissible to humans. In this study, two single genes, respectively coding for dipeptidyl peptidases IV and V (DppIV and DppV), were isolated and characterized. Both proteins share homology with serine proteases of the S9 family, some of which display properties compatible with implication in pathogenic processes. Both genes are expressed in vivo in experimentally infected guinea-pigs and in naturally infected cats, and when the fungus is grown on extracellular matrix proteins as the sole nitrogen and carbon source. DppIV and V were produced as active recombinant proteases in the yeast Pichia pastoris; the apparent molecular weight of rDppV is 83 kDa, whereas rDppIV appears as a doublet of 95 and 98 kDa. Like other members of its enzymatic subfamily, rDppIV has an unusual ability to cleave Pro-X bonds. This activity does not enhance the solubilization of keratin by fungal secreted endoproteases, and the protease probably acts solely on small soluble peptides. RDppV showed no ability to induce delayed-type hypersensitivity (DTH) skin reactions in guinea-pigs, despite the known immunogenic properties of homologous proteins. [less ▲]

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See detailLes nouveaux antiparasitaires chez le chien et le chat
Losson, Bertrand ULg

in Nouveau praticien vétérinaire (2008)

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See detailEvolution of the clinical expression of Bluetongue in Belgian cattle during year 2006 vs 2007
Guyot, Hugues ULg; Mauroy, Axel ULg; Rollin, Frédéric ULg et al

Conference (2008)

In August 2006, Belgium notified its first cases of Bluetongue (BT), serotype 8, in cattle and sheep. The disease was also observed at this time in the neighboring countries. The resurgence of BT was ... [more ▼]

In August 2006, Belgium notified its first cases of Bluetongue (BT), serotype 8, in cattle and sheep. The disease was also observed at this time in the neighboring countries. The resurgence of BT was observed in Northern Europe in 2007. The aim of the study was to compare clinical signs of BT observed in 2006 vs 2007 in Belgian cattle. The description of clinical signs was based on the observation of 38 and 39 cows in 2006 and 2007, respectively. BT cases were only included if they were confirmed by one or both laboratory diagnostic tests (competitive ELISA test and/or RT-qPCR). The inventory of clinical signs was made with a standardised clinical form for BT. This form is divided into general, cutaneous, locomotor, digestive, respiratory, neurological and reproductive clinical signs. Case data were summarised to determine changes in clinical presentation of BT between 2006 and 2007. A Fischer’s exact probability test was performed to compare (P<0.05) the frequency of clinical signs between the two years. Regarding general clinical signs, hyperthermia and tiredness were more often observed in 2007, compared to 2006. All clinical signs about skin and annexes were not significantly different between the two years. Locomotor signs such as prostration, incapacity to get up, reluctance to move, lameness and amyotrophy were more frequent in 2007. Loss of appetite, difficulties in grasping feed, salivation and drooling were the digestive signs more often observed in 2007. A purulent nasal discharge was the only respiratory sign more commonly observed in 2007. Apathy, generalised weakness and paresis or paralysis were more often encountered in 2007. The most important changes between the two years concerned reproduction. A higher incidence of abortion, premature calving and stillbirth was observed during 2007 outbreak. The frequency of most of the clinical signs of BT was higher in 2007 in Belgian cattle. Confirmed cases of BT in Belgian cattle were only 296 in 2006 compared to 4187 in 2007. These data do not represent the real situation of BT infection because the farmers do not notify all cases. Nevertheless, it seems that the 2007 outbreak was more severe regarding the number of cases and the frequency of clinical signs. The mild winter and wet 2007 summer might have favored the persistence of the vectors. [less ▲]

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See detailFasciola hepatica: an assessment on the vectorial capacity of Radix labiata and R. balthica commonly found in Belgium.
Caron, Yannick ULg; LASRI, Saadia ULg; Losson, Bertrand ULg

in Veterinary Parasitology (2007), 149(1-2), 95-103

A previous study conducted in Belgium revealed that genetic material of Fasciola sp. was present in snail species belonging to the genus Radix. Here, these snails were collected and identified by DNA ... [more ▼]

A previous study conducted in Belgium revealed that genetic material of Fasciola sp. was present in snail species belonging to the genus Radix. Here, these snails were collected and identified by DNA-based techniques as Radix labiata and Radix balthica. These two species and Galba truncatula (the major intermediate host in Europe) were experimentally infected with Fasciola hepatica. The resulting metacercariae were fed to rats and the infection was monitored using several techniques. Microscopy revealed the presence of larval stages in 78.3, 45, and 6.25% of G. truncatula, R. labiata, and R. balthica snails, respectively. These results were confirmed by a PCR that amplifies a Fasciola sp. specific sequence. Furthermore, this PCR was found to be more sensitive than microscopic examination. R. labiata shed fewer metacercariae than G. truncatula but these were as infective to rats as those shed by G. truncatula. This study demonstrates that R. labiata may act as an incidental intermediate host for F hepatica in Belgium. (C) 2007 Elsevier B.V. All rights reserved. [less ▲]

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See detailRNA silencing in the dermatophyte Microsporum canis
Vermout, S.; Tabart, J.; Baldo, Aline ULg et al

in FEMS Microbiology Letters (2007), 275(1), 38-45

Dermatomycoses caused by Microsporum canis are frequent in domestic animals and easily transmissible to humans. Several proteases secreted by this fungus were identified as potential virulence factors ... [more ▼]

Dermatomycoses caused by Microsporum canis are frequent in domestic animals and easily transmissible to humans. Several proteases secreted by this fungus were identified as potential virulence factors, but the construction of deficient strains is required to investigate their role in the pathogenesis of the disease. Using target genes encoding two of these proteases, a first evaluation of the utility of RNA-mediated silencing as a reverse genetic tool in dermatophytes was carried out. SUB3 and DPPIV, respectively coding for a subtilisin and a dipeptidyl peptidase, were both down-regulated, by means of two plasmid constructs designed to express an RNA hairpin that corresponds to part of their respective sequence. The degree of attenuation was evaluated by enzymatic assay of the transformants culture supernatants, and by real-time reverse transcriptase-polymerase chain reaction. Enzymatic activities and expression levels varied from less than 5% to 100% of that of control transformants obtained with plasmid without hairpin inserts. Inhibition was globally more efficient for SUB3 than for DPPIV. These results show that RNA silencing can be used for functional genomics in M. canis, and particularly to circumvent the limits and technical difficulties of conventional disruption methods. [less ▲]

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See detailFasciola hepatica: An assessment of the vectorial capacity of Radix labiata and R. balthica commonly found in Belgium
Caron, Yannick ULg; Lasri, Saadia; Losson, Bertrand ULg

Conference (2007, August)

A previous study in Belgium revealed that genetic material of Fasciola sp. was present in four local snail species: Galba truncatula, Radix peregra, Radix ovata and Lymnaea stagnalis. Laboratory cultures ... [more ▼]

A previous study in Belgium revealed that genetic material of Fasciola sp. was present in four local snail species: Galba truncatula, Radix peregra, Radix ovata and Lymnaea stagnalis. Laboratory cultures of these four species were experimentally infected with F. hepatica. The collected metacercariae were fed to rats and the infection in that vertebrate hosts was monitored through several techniques. The mortality rates in the breeding unit was less than 10 % in G. truncatula, R. peregra, and L. stagnalis colonies. Microscopy revealed the presence of larval stages in 78.3 % and 48 % of G. truncatula and R. peregra snails, respectively. These data were confirmed by a PCR that amplifies a parasite specific sequence. R. peregra shed fewer metacercariae and more irregularly than G. truncatula. In R. ovata and L. stagnalis the infection rates were low. Specific DNA was detected in both cases by PCR but no metacercariae were shed. The metacercariae shed by R. peregra were as infective to rats as those from G. truncatula. The PCR technique was more sensitive than microscopic examination. This study demonstrated that R. peregra may act as an accidental intermediate host for F. hepatica in Belgium. [less ▲]

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See detailReconstructed interfollicular feline epidermis as a model for Microsporum canis dermatophytosis
Tabart, Jérémy; Baldo, Aline ULg; Vermout, Sandy et al

in Journal of Medical Microbiology (2007), 56(7), 971-975

Microsporum canis is a pathogenic fungus that causes a superficial cutaneous infection called dermatophytosis. The complexity of mechanisms involved in dermatophytic infections makes relevant in vivo ... [more ▼]

Microsporum canis is a pathogenic fungus that causes a superficial cutaneous infection called dermatophytosis. The complexity of mechanisms involved in dermatophytic infections makes relevant in vivo studies particularly difficult to perform. The aim of this study was to develop a new in vitro model of M. canis dermatophytosis using feline fetal keratinocytes in reconstructed interfollicular epidermis, and to investigate its relevance in studying the host-pathogen relationship. Histological analysis of reconstructed interfollicular feline epidermis (RFE) revealed a fully differentiated epidermis. A proliferation assay showed replicating cells only in the basal layer, indicating that RFE is a well-stratified living tissue, leading to the formation of a horny layer. Histopathological analysis of RFE infected by M. canis arthroconidia revealed that the fungus invades the stratum corneum and produces SUB3, a keratinase implicated in the infectious process. In view of these results, an M. canis dermatophytosis model on RFE seems to be a useful tool to investigate mechanisms involved in natural M. canis feline infections. [less ▲]

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See detailEchinococcus multilocularis and Toxocara canis in urban red foxes (Vulpes vulpes) in Brussels, Belgium
Brochier, B.; De Blander, H.; Hanosset, R. et al

in Preventive Veterinary Medicine (2007), 80(1), 65-73

During the last decades, European red foxes (Vulpes vulpes) have been implicated in the transmission of several viral or parasitic pathogenic agents to domestic animals and humans. In urban areas, risks ... [more ▼]

During the last decades, European red foxes (Vulpes vulpes) have been implicated in the transmission of several viral or parasitic pathogenic agents to domestic animals and humans. In urban areas, risks of zoonoses transmission are likely to increase as a result of a higher rate of intra and inter-species contacts. Foxes occur on 35% of the Brussels-Capital Region area and local densities reach up to 4 family groups per square kilometre. According to the directive 2003/99/ECC, a first survey for the presence in foxes of Echinococcus multilocularis and Toxocara canis was conducted in Brussels from 2001 to 2004. None of 160 foxes were found to be infected with E. multilocularis and 24 of 134 foxes were found to be infected with T canis. Considering numbers of examined foxes, the sensitivity and the specificity of tests used for diagnosis, the 95% credibility intervals for the true prevalence of E. multilocularis and T canis were estimated in a Bayesian framework to be 0 to 1.87% (median value of 0%) and 12.7 to 26% (median value of 18.7%), respectively. For T canis, a significantly higher risk to be a carrier occurs in cubs and a significantly lower risk in adults. (c) 2007 Elsevier B.V. All rights reserved. [less ▲]

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See detailLes mécanismes d'adhérence des champignons responsables de mycoses superficielles
Baldo, Aline ULg; Mathy, Anne ULg; Vermout, S. et al

in Annales de Médecine Vétérinaire (2007), 151

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See detailBovine babesiosis in Belgium: preliminary results of a postal survey of veterinarians in 2006
Saegerman, Claude ULg; Claerebout, E.; Kalume, M. et al

in Rencontres autour des Recherches sur les Ruminants (2007), 14

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See detailDescription clinique des cas de FCO survenus au Nord de l'Europe durant l'été et l'automne 2006
Guyot, Hugues ULg; Mauroy, Axel ULg; Thiry, Etienne ULg et al

in Bulletin des Groupements Techniques Vétérinaires (2007), 39(avril), 89-96

La fièvre catarrhale ovine (FCO) a été identifiée au Nord de l’Europe <br />le 14 août 2006. L’Allemagne, la Belgique, les Pays-Bas et, dans une <br />moindre mesure, le Grand-Duché de Luxembourg et la ... [more ▼]

La fièvre catarrhale ovine (FCO) a été identifiée au Nord de l’Europe <br />le 14 août 2006. L’Allemagne, la Belgique, les Pays-Bas et, dans une <br />moindre mesure, le Grand-Duché de Luxembourg et la France ont été <br />affectés. Le sérotype 8 du virus de la FCO (exotique) a rapidement été <br />identifié ainsi qu’un vecteur, Culicoides dewulfi, une espèce indigène du <br />Nord de l’Europe. La maladie s’est rapidement développée et au 1er <br />février 2007, on recensait 2137 foyers de FCO, toutes espèces de <br />ruminants confondues. Globalement, la maladie a affecté davantage les <br />bovins (54 %) que les ovins (46 %). Les signes cliniques les plus <br />fréquemment observés chez les bovins étaient des lésions sur le museau <br />et la cavité buccale (ulcérations/croûtes), de la salivation et des boiteries <br />chez des animaux adultes. La morbidité et la mortalité animales étaient <br />respectivement de maximum 5 % et 1 %. Les principaux signes cliniques <br />rencontrés chez le mouton étaient également des lésions sur le museau <br />et la cavité buccale (ulcérations/croûtes), de l’amaigrissement et des <br />boiteries. La morbidité et la mortalité animales étaient respectivement <br />de maximum 12 % et 6 %. Les signes cliniques n’étant pas <br />pathognomoniques et le diagnostic différentiel relativement vaste, seul <br />un examen de laboratoire permet d’établir un diagnostic de certitude. [less ▲]

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See detailBiting Midges Overwintering In Belgium
Losson, Bertrand ULg; Mignon, Bernard ULg; Paternostre, Julien ULg et al

in Veterinary Record : Journal of the British Veterinary Association (2007), 160(13), 451-452

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See detailReconstructed interfollicular feline epidermis as a model for the screening of drugs against Microsporum canis
Mignon, Bernard ULg; Tabart, J.; Baldo, Aline ULg et al

in Veterinary Dermatology (2007), 18

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See detailDiagnostic et surveillance épidémiologique de Neospora caninum
Ghalmi, F.; China, B.; Losson, Bertrand ULg

in Annales de Médecine Vétérinaire (2007), 151

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See detailFièvre Catarrhale Ovine chez les ruminants. Description clinique des cas vécus dans le Nord de l’Europe durant l’été-automne 2006
Guyot, Hugues ULg; Mauroy, Axel ULg; Thiry, Etienne ULg et al

in Bulletin des GTV (2007)

La fièvre catarrhale ovine (FCO) a été identifiée au Nord de l’Europe le 14 août 2006. L’Allemagne, la Belgique, les Pays-Bas et, dans une moindre mesure, le Grand-Duché de Luxembourg et la France ont été ... [more ▼]

La fièvre catarrhale ovine (FCO) a été identifiée au Nord de l’Europe le 14 août 2006. L’Allemagne, la Belgique, les Pays-Bas et, dans une moindre mesure, le Grand-Duché de Luxembourg et la France ont été affectés. Le sérotype 8 du virus de la FCO (exotique) a rapidement été identifié ainsi qu’un vecteur, Culicoides dewulfi, une espèce indigène du Nord de l’Europe. La maladie s’est rapidement développée et au 1er février 2007, on recensait 2137 foyers de FCO, toutes espèces de ruminants confondues. Globalement, la maladie a affecté davantage les bovins (54 %) que les ovins (46 %). Les signes cliniques le plus fréquemment observés chez les bovins étaient des lésions sur le museau et la cavité buccale (ulcérations/croûtes), de la salivation et des boiteries chez des animaux adultes. La morbidité et la mortalité animales étaient respectivement de maximum 5 % et 1 %. Les principaux signes cliniques rencontrés chez le mouton étaient également des lésions sur le museau et la cavité buccale (ulcérations/croûtes), de l’amaigrissement et des boiteries. La morbidité et la mortalité animales étaient respectivement de maximum 12 % et 6 %. Les signes cliniques n’étant pas pathognomoniques et le diagnostic différentiel relativement vaste, seul un examen de laboratoire permet de poser un diagnostic de certitude. [less ▲]

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