References of "Farnir, Frédéric"
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See detailGaseous emissions in the raising of weaned pigs on fully slatted floor or on sawdust-based deep litter
Nicks, Baudouin ULg; Laitat, Martine ULg; Farnir, Frédéric ULg et al

in Proceedings of the International workshop on Green Pork Production (2005)

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See detailReal-time RT-PCR quantification of mRNA encoding cytokines and chemokines in histologically normal canine nasal, bronchial and pulmonary tissue
Peeters, Dominique ULg; Peters, I. R.; Farnir, Frédéric ULg et al

in Veterinary Immunology and Immunopathology (2005), 104(3-4), 195-204

Cytokines and chemokines are likely to be involved in the pathogenesis of inflammatory diseases of the canine respiratory tract. The roles and relative amounts of these molecules have not yet been defined ... [more ▼]

Cytokines and chemokines are likely to be involved in the pathogenesis of inflammatory diseases of the canine respiratory tract. The roles and relative amounts of these molecules have not yet been defined in the respiratory mucosa of normal dogs or dogs with naturally acquired respiratory inflammation. In the present study, real-time reverse transcriptase polymerase chain reaction (RT-PCR) assays were employed to quantify messenger RNA (mRNA) encoding the chemokines monocyte chernotactic protein (MCP)-2, eotaxin-2 and eotaxin-3, and the cytokines interleukin-4 (IL-4), IL-5, IL-6, IL-10, IL-12p40, IL-18, interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta) in normal nasal, bronchial and pulmonary tissues from puppies (n = 4) and from adult dogs (n = 7). There was no significant difference in the expression of any transcript between puppies and adult dogs at any of the anatomical sites examined. The expression of mRNA encoding eotaxin-2 and eotaxin-3 increased significantly with progression from the nasal mucosa to pulmonary parenchyma but expression of MCP-2 mRNA did not show this trend. At all levels of the respiratory mucosa, the most abundant transcripts were those encoding IL-18 and TGF-beta. Transcripts encoding IL-6, IL-10, IL-12 and TNF-alpha were approximately ten-fold less abundant, and IL-4, IL-5 and IFN-gamma were the least abundant templates. There was significantly different amount of mRNA encoding IL-5, IL- 18 and TNF-alpha between particular anatomical levels of the respiratory mucosa while the mRNA expression of the other cytokines was similar at all anatomical sites. The results of the present study will enable comparisons to be made with results obtained from similar samples obtained from dogs with nasal, bronchial or pulmonary diseases. (c) 2004 Elsevier B.V. All rights reserved. [less ▲]

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See detailDistribution of leucocyte subsets in the canine respiratory tract
Peeters, Dominique ULg; Day, M. J.; Farnir, Frédéric ULg et al

in Journal of Comparative Pathology (2005), 132(4), 261-272

Histochemistry and immunohistochemistry were used to characterize leucocyte subsets in the respiratory tract of 15 outbred dogs (five aged <6 months and 10 aged >1 year) that had no evidence of ... [more ▼]

Histochemistry and immunohistochemistry were used to characterize leucocyte subsets in the respiratory tract of 15 outbred dogs (five aged <6 months and 10 aged >1 year) that had no evidence of respiratory disease. No organized nose- or bronchus-associated lymphoid tissue was observed in any of the sections examined. IgA(+) plasma cells predominated in nasal mucosa and in all parts of the bronchial tree, with fewer IgG(+) and IgM(+) plasma cells. The numbers of IgA(+) and IgM(+) cells were significantly greater in the nasal mucosa than in any other part of the respiratory mucosa. There were significantly fewer IgA(+), IgG(+) and IgM(+) cells in all parts of the respiratory tract in the puppies than in the adults. The number and distribution of mast cells and cells expressing MHC class II, L1 or CD1c were recorded. Mast cells were mainly found in the subepithelial lamina propria of nasal and bronchial mucosa and in the alveolar interstitium, and cells expressing IgE had a similar distribution. Mast cells were also present within muscle layers of the bronchial tree. The numbers of mast cells and MHC class II(+) cells were significantly greater in the nasal mucosa than in any other part of the respiratory mucosa. In the nose, carina and primary and secondary bronchus, there were significantly more mast cells and MHC class II(+) cells in puppies than in adult dogs, whereas the numbers of L1(+) cells and CD1c(+) cells in most sites were significantly greater in older dogs. There were significantly more CD3(+) and CD8(+) cells in the nasal mucosa than in any part of the bronchial mucosa. In most parts of the respiratory mucosa, CD4(+), CD8(+) and TCR alphabeta(+) cells were present in significantly greater numbers in adults than in puppies. All parts of the respiratory tract had similar numbers of mucosal CD4(+) and CD8(+) T lymphocytes. TCR gammadelta(+) cells were absent or sparse in all samples. These data, obtained from dogs without respiratory disease, will enable comparisons to be made with dogs suffering from infectious or inflammatory nasal, bronchial and pulmonary diseases. [less ▲]

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See detailCharacterisation and control of the reproduction and growth parameters of Djallonke ovines (Ovis amon aries)
Gbangboche, Armand; Hornick, Jean-Luc ULg; Adamou-N'Diaye, Maman et al

in Annales de Médecine Vétérinaire (2005), 149(3), 148-160

Plusieurs années d’efforts de recherches témoignent que l’élevage des ovins Djallonké est une activité majeure dans l’Afrique subsaharienne, si l’on en juge par la masse des connaissances produites. Les ... [more ▼]

Plusieurs années d’efforts de recherches témoignent que l’élevage des ovins Djallonké est une activité majeure dans l’Afrique subsaharienne, si l’on en juge par la masse des connaissances produites. Les auteurs, au travers d’un inventaire des différentes contributions scientifiques et techniques de 1967 à 2004, rapportent les performances de reproduction et de croissance des ovins Djallonké et les facteurs de leur variation. Les performances de reproduction ont été évaluées au travers de six critères zootechniques : cyclicité sexuelle annuelle, précocité sexuelle, intervalle entre agnelages, productions laitières, prolificité et mortalité des agneaux. Les performances de croissance ont été étudiées pendant deux périodes : la période d’allaitement naturel (croissance entre naissance et sevrage) et la période post sevrage. Les estimations des paramètres génétiques (héritabilité, corrélations génétiques et phénotypiques, répétabilité) de quelques caractères de reproduction et de croissance, ainsi que les résultats d’amélioration génétique, ont été passés en revue. Les conseils pratiques sont loin d’être uniformes étant donné la grande diversité des conditions d’expérimentation et d’analyse entre les différentes publications. [less ▲]

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See detailGaseous emissions in the raising of fattening pigs on fully slatted floor or on straw-based deep litter
Nicks, Baudouin ULg; Philippe, François-Xavier ULg; Laitat, Martine ULg et al

in Proceedings of the XIIth international congress of the International Society for animal Hygiene, Animals and the environment (2005)

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See detailEctopic expression of DLK1 protein in skeletal muscle of padumnal heterozygotes causes the callipyge phenotype
Davis, Erica; Jensen, C.; Schroder, H. D. et al

in Current Biology (2004), 14(20), 1858-1862

The callipyge (CLPG) phenotype is an inherited skeletal muscle hypertrophy described in sheep. It is characterized by an unusual mode of inheritance ("polar overdominance") in which only heterozygous ... [more ▼]

The callipyge (CLPG) phenotype is an inherited skeletal muscle hypertrophy described in sheep. It is characterized by an unusual mode of inheritance ("polar overdominance") in which only heterozygous individuals having received the CLPG mutation from their father (+(MAT)/CLPG(PAT)) express the phenotype . +(MAT)/CLPG(PAT) individuals are born normal and develop the muscular hypertrophy at approximately 1 month of age. The CLPG mutation was identified as an A to G transition in a highly conserved dodecamer motif located between the imprinted DLK1 and GTL2 genes . This motif is thought to be part of a long-range control element (LRCE) because the CLPG mutation was shown, in postnatal skeletal muscle, to enhance the transcript levels of the DLK1, PEG11, GTL2, and MEG8 genes in cis without altering their imprinting status . As a result, the +(MAT)/CLPG(PAT) individuals have a unique expression profile thought to underlie the callipyge phenotype: an overexpression of the paternally expressed protein encoding DLK1 (Figure 1A) and PEG11 transcripts in the absence of an overexpression of the maternally expressed noncoding GTL2 and MEG8 transcripts . However, the way in which this distinct expression profile causes the callipyge muscular hypertrophy has remained unclear. Herein, we demonstrate that the callipyge phenotype is perfectly correlated with ectopic expression of DLK1 protein in hypertrophied muscle of +(MAT)/CLPG(PAT) sheep. We demonstrate the causality of this association by inducing a generalized muscular hypertrophy in transgenic mice that express DLK1 in skeletal muscle. The absence of DLK1 protein in skeletal muscle of CLPG/CLPG animals, despite the presence of DLK1 mRNA, supports a trans inhibition mediated by noncoding RNAs expressed from the maternal allele. [less ▲]

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See detailGenetic and functional confirmation of the causality of the DGAT1 K232A quantitative trait nucleotide in affecting milk yield and composition
Grisart, B.; Farnir, Frédéric ULg; Karim, Latifa ULg et al

in Proceedings of the National Academy of Sciences of the United States of America (2004), 101(8), 2398-2403

We recently used a positional cloning approach to identify a nonconservative lysine to alanine substitution (K232A) in the bovine DGAT1 gene that was proposed to be the causative quantitative trait ... [more ▼]

We recently used a positional cloning approach to identify a nonconservative lysine to alanine substitution (K232A) in the bovine DGAT1 gene that was proposed to be the causative quantitative trait nucleotide underlying a quantitative trait locus (QTL) affecting milk fat composition, previously mapped to the centromeric end of bovine chromosome 14. We herein generate genetic and functional data that confirm the causality of the DGAT1 K232A mutation. We have constructed a high-density single-nucleotide polymorphism map of the 3.8-centimorgan BULGE30-BULGE9 interval containing the QTL and show that the association with milk fat percentage maximizes at the DGAT1 gene. We provide evidence that the K allele has undergone a selective sweep. By using a baculovirus expression system, we have expressed both DGAT1 alleles in Sf9 cells and show that the K allele, causing an increase in milk fat percentage in the live animal, is characterized by a higher V-max in producing triglycerides than the A allele. [less ▲]

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See detailProduction des ovins Djallonké en station dans la zone guinéenne au Bénin : 1. Performances de reproduction et influence des facteurs non génétiques
Gbangboche, A. B.; Hounzangbe-Adote, S. M.; Doko, S. Y. et al

in Revue Africaine de Santé et de Productions Animales [=RASPA] (2004), 2

Production of Djallonke sheep at an experimental station in the guinean zone of Benin. Reproduction performance and influence of non-genetic factors From 1994 to 2002, data from Djallonke sheep were ... [more ▼]

Production of Djallonke sheep at an experimental station in the guinean zone of Benin. Reproduction performance and influence of non-genetic factors From 1994 to 2002, data from Djallonke sheep were collected for reproduction performance. The data were obtained from the farm of the Faculty of Agronomic Sciences (University of Abomey Calavi). Data analysed by GLM procedure and Student’s t-test, were used to identify and quantify non-genetics factors affecting the age at first lambing, intervals between lambing and prolificacy. Results indicated: age at first lambing, 609.64days±110.26 days; intervals between lambing, 243.01days±68.19days; prolificity, 1.28±0.45; annual reproduction rate, 1.92%; temporary sterility rate, 5.79%. Lambing season, lambing year and the year*season interaction affected significantly (p<0.01) the age at first lambing and the interval between lambing. The same factors were not significant (p>0.05) for prolificacy. [less ▲]

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See detailGaseous emissions from deep-litter pens with straw or sawdust for fattening pigs
Nicks, Baudouin ULg; Laitat, Martine ULg; Farnir, Frédéric ULg et al

in Animal Science (2004), 78(Part 1), 99-107

Three successive batches of fattening pigs were raised on a deep litter of straw in one room and of sawdust in another. The quantities of litter used per pig were 40 kg of straw and 81 kg of sawdust. Once ... [more ▼]

Three successive batches of fattening pigs were raised on a deep litter of straw in one room and of sawdust in another. The quantities of litter used per pig were 40 kg of straw and 81 kg of sawdust. Once a month, the emissions of ammonia, nitrous oxide, methane, carbon dioxide and water vapour were measured continuously for 6 days consecutively. Gaseous emissions from pig raising on sawdust-based litter and straw-based litter were respectively 12.16 and 13.61 g per pig per day for ammonia (NH3), 4.96 and 7.39 g per pig per day for methane (CH4), 2.09 and 0.03 g per pig per day for nitrous oxide (N2O), 3.15 and 2.74 kg per pig per day for water (H2O) and 1.32 and 1.30 kg per pig per day for carbon dioxide (CO2). Differences between the emissions of the two litters were significant for N2O and H2O (P < 0.01). The nitrogen content of the manures collected at the end of the experiment was 1.47 kg per pig for the straw-based litter and 1.07 kg per pig for that based on sawdust. Nitrogen emissions were calculated under the assumption that no gases volatilized from the litter or from the animals other than NH3 and N2O. With the two litters, about 50% of nitrogen excreted by the pigs was emitted into the atmosphere in the form of N-2. [less ▲]

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See detailGaseous emissions in the raising of weaned pigs on fully slatted floor or on straw-bases deep litter
Nicks, Baudouin ULg; Laitat, Martine ULg; Farnir, Frédéric ULg et al

in Clement, G.; Madec, F. (Eds.) Proceedings of the in- between congress of the International Society for Animal Hygiene (2004)

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See detailInvestigation of the susceptibility of human cell lines to bovine herpesvirus 4 infection: Demonstration that human cells can support a nonpermissive persistent infection which protects them against tumor necrosis factor alpha-induced apoptosis
Gillet, Laurent ULg; Minner, F.; Detry, Bruno et al

in Journal of Virology (2004), 78(5), 2336-2347

Bovine herpesvirus 4 (BoHV-4) is a gammaherpesvirus that has a worldwide distribution in the population of cattle. Many factors make human contamination by BoHV-4 likely to occur. In this study, we ... [more ▼]

Bovine herpesvirus 4 (BoHV-4) is a gammaherpesvirus that has a worldwide distribution in the population of cattle. Many factors make human contamination by BoHV-4 likely to occur. In this study, we performed in vitro experiments to assess the risk and the consequences of human infection by BoHV-4. First, by using a recombinant BoHV-4 strain expressing enhanced green fluorescent protein under the control of the human cytomegalovirus immediate-early gene promoter, we tested 21 human cell lines for their sensitivity and their permissiveness to BoHV-4 infection. These experiments revealed that human cell lines from lymphoid and myeloid origins were resistant to infection, whereas epithelial cells, carcinoma cells, or adenocarcinoma cells isolated from various organs were sensitive but poorly permissive to BoHV-4 infection. Second, by using the HeLa cell line as a model of human cells sensitive but not permissive to BoHV-4 infection, we investigated the resistance of infected cells to apoptosis and the persistence of the infection through cellular divisions. The results obtained can be summarized as follows. (i) BoHV-4 nonpermissive infection of HeLa cells protects them against tumor necrosis factor alpha-induced apoptosis. (ii) BoHV-4 infection of HeLa cells persists in cell culture; however, the percentage of infected cells decreases with time due to erratic transmission of the viral genome through cell division. (iii) BoHV-4 infection has no effect on the rate of HeLa cell division. Altogether, these data suggest that BoHV-4 could infect humans. This study also stresses the importance of considering the insidious effects of nonpermissive infection when the biosafety of animal gammaherpesviruses for humans is being considered. [less ▲]

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See detailAdherence of Mycoplasma bovis to bovine bronchial epithelial cells
Thomas, Anne; Sachse, K.; Farnir, Frédéric ULg et al

in Microbial Pathogenesis (2003), 34(3), 141-148

Mycoplasma bovis is responsible for considerable economic losses in cattle due to pneumonia, arthritis and mastitis. As the agent was shown to be capable of adhering to neutrophils and embryonic bovine ... [more ▼]

Mycoplasma bovis is responsible for considerable economic losses in cattle due to pneumonia, arthritis and mastitis. As the agent was shown to be capable of adhering to neutrophils and embryonic bovine lung (EBL) cells and invading the respiratory epithelium it is highly desirable to improve our understanding of cytadherence processes. Although several surface proteins likely to be directly involved in this initial stage of interaction between pathogen and host cells have been identified, these findings mainly referred to type strain PG45 adhering to the continuous EBL cell line. The present study provides new and complementary data about cytadherence of M. bovis based on adherence of various radiolabeled strains to a primary culture of bovine bronchial epithelial (BBE) cells using a standardized adherence assay. M. bovis was shown to adhere specifically to the primary culture of BBE cells. Inhibition of adherence was observed upon addition of monoclonal antibodies (MAbs), trypsin treatment of mycoplasmas, and competition with non-radiolabeled mycoplasma cells. Interestingly, three MAbs against proteins involved in adherence to EBL cells failed to inhibit significantly the adherence to BBE cells. On the other hand, significant reduction of adherence rates by MAbs 2A8 and 9F1 directed against epitopes of variable surface lipoproteins VspC and VspF, respectively, demonstrated the involvement of these proteins in adherence of M. bovis to primary culture of BBE cells. (C) 2003 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailModulating skeletal muscle mass by postnatal, muscle-specific inactivation of the myostatin gene.
Grobet, Luc ULg; Pirottin, Dimitri ULg; Farnir, Frédéric ULg et al

in Genesis (2003), 35(4), 227-38

By using a conditional gene targeting approach exploiting the cre-lox system, we show that postnatal inactivation of the myostatin gene in striated muscle is sufficient to cause a generalized muscular ... [more ▼]

By using a conditional gene targeting approach exploiting the cre-lox system, we show that postnatal inactivation of the myostatin gene in striated muscle is sufficient to cause a generalized muscular hypertrophy of the same magnitude as that observed for constitutive myostatin knockout mice. This formally demonstrates that striated muscle is the production site of functional myostatin and that this member of the TGFbeta family of growth and differentiation factors regulates muscle mass not only during early embryogenesis but throughout development. It indicates that myostatin antagonist could be used to treat muscle wasting and to promote muscle growth in man and animals. [less ▲]

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See detailAdherence to various host cell lines of Mycoplasma bovis strains differing in pathogenic and cultural features
Thomas, Anne; Sachse, Konrad; Dizier, Isabelle ULg et al

in Veterinary Microbiology (2003), 91(2-3), 101-113

Mycoplasma bovis is known to be responsible for pneumonia and arthritis in calves, as well as mastitis in dairy cows. Despite clear evidence of its pathogenic potential, little is known about mechanisms ... [more ▼]

Mycoplasma bovis is known to be responsible for pneumonia and arthritis in calves, as well as mastitis in dairy cows. Despite clear evidence of its pathogenic potential, little is known about mechanisms of cytadherence and the molecular factors involved. The purpose of this work was to compare adherence rates of M. bovis field strains to different host cell lines and study the effects of cloning and sub-culturing M. bovis strains on their adherence properties. Eighteen metabolically labeled M. bovis strains isolated from different pathological backgrounds were examined in adherence trials using four different host cell lines, i.e. embryonic bovine lung (EBL), embryonic bovine trachea (EBTr), Madin Darby bovine kidney (MDBK) and rabbit kidney (RK) cells. Although large interstrain variations in adherence rates (3.4-19.1%) were measured they could not be correlated to the pathological background (pneumonia, arthritis or mastitis). Adherence rates to the fibroblast cell line (EBTr) were significantly lower than those to the three epithelial cell lines (EBL, MDBK and RK). The only non-pathogenic strain (221/89) exhibited lower adherence rates than three isolates from clinical mastitis. Interestingly, adherence rates were significantly reduced after in vitro passaging. In contrast, no effect of single cloning of strains on adherence was observed. There was no general correlation between expression of variable surface proteins (Vsps) as monitored by immunoblotting and adherence rates, although alterations in Vsp expression profiles were seen as a consequence of passaging. As there is probably a large number of adhesins, variable and non-variable, on the surface of M. bovis cells the issue is very complex, and the most active components have yet to be identified. [less ▲]

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See detailMolecular dissection of a quantitative trait locus: a phenylalanine-to-tyrosine substitution in the transmembrane domain of the bovine growth hormone receptor is associated with a major effect on milk yield and composition.
Blott, Sarah; Kim, Jong-Joo; Moisio, Sirja et al

in Genetics (2003), 163(1), 253-66

We herein report on our efforts to improve the mapping resolution of a QTL with major effect on milk yield and composition that was previously mapped to bovine chromosome 20. By using a denser chromosome ... [more ▼]

We herein report on our efforts to improve the mapping resolution of a QTL with major effect on milk yield and composition that was previously mapped to bovine chromosome 20. By using a denser chromosome 20 marker map and by exploiting linkage disequilibrium using two distinct approaches, we provide strong evidence that a chromosome segment including the gene coding for the growth hormone receptor accounts for at least part of the chromosome 20 QTL effect. By sequencing individuals with known QTL genotype, we identify an F to Y substitution in the transmembrane domain of the growth hormone receptor gene that is associated with a strong effect on milk yield and composition in the general population. [less ▲]

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See detailPositional candidate cloning of a QTL in dairy cattle: Identification of a missense mutation in the bovine DGAT1 gene with major effect on milk yield and composition
Grisart, B.; Coppieters, Wouter ULg; Farnir, Frédéric ULg et al

in Genome Research (2002), 12(2), 222-231

We recently mapped a quantitative trait locus (QTL) with a major effect on milk composition-particularly fat content-to the centromeric end of bovine chromosome 14. We subsequently exploited linkage ... [more ▼]

We recently mapped a quantitative trait locus (QTL) with a major effect on milk composition-particularly fat content-to the centromeric end of bovine chromosome 14. We subsequently exploited linkage disequilibrium to refine the map position of this QTL to a 3-cM chromosome interval bounded by microsatellite markers BULGE13 and BULGE09. We herein report the positional candidate cloning of this QTL, involving (I) the construction of a BAC contig spanning the corresponding marker interval, (2) the demonstration that a very strong candidate gene, acylCoA:diacylglycerol acyltransferase (DGATf), maps to that contig, and (3) the identification of a nonconservative K232A substitution in the DGAT1 gene with a major effect on milk fat content and other milk characteristics. [less ▲]

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See detailSimultaneous mining of linkage and linkage disequilibrium to fine map quantitative trait loci in outbred half-sib pedigrees: Revisiting the location of a quantitative trait locus with major effect on milk production on bovine chromosome 14
Farnir, Frédéric ULg; Grisart, B.; Coppieters, Wouter ULg et al

in Genetics (2002), 161(1), 275-287

A maximum-likelihood QTL mapping method that simultaneously exploits linkage and linkage disequilibrium and that is applicable in outbred half-sib pedigrees is described. The method is applied to fine map ... [more ▼]

A maximum-likelihood QTL mapping method that simultaneously exploits linkage and linkage disequilibrium and that is applicable in outbred half-sib pedigrees is described. The method is applied to fine map a QTL with major effect on milk fat content in a 3-cM marker interval on proximal BTA14. This proximal location is confirmed by applying a haplotype-based association method referred to as recombinant ancestral haplotype analysis. The origin of the discrepancy between the QTL position derived in this work and that of a previous analysis is examined and shown to be due to the existence of distinct marker haplotypes associated with QTL alleles having large substitution effects. [less ▲]

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See detailCell-Mediated Immune Response in Calves to Single-Dose, Trickle, and Challenge Infections with Fasciola Hepatica
Bossaert, K.; Jacquinet, E.; Saunders, J. et al

in Veterinary Parasitology (2000), 88(1-2), 17-34

A peripheral blood mononuclear cell (PBMC) proliferation assay was used to study the cell-mediated immune response in eight calves experimentally infected with Fasciola hepatica. Hypersensitivity-related ... [more ▼]

A peripheral blood mononuclear cell (PBMC) proliferation assay was used to study the cell-mediated immune response in eight calves experimentally infected with Fasciola hepatica. Hypersensitivity-related eosinophil and mast-cell responses were also assessed. The primary infection of 500 metacercariae was administered either as a single-dose or as a trickle infection over a 4-week period. Calves were challenge-infected 4 months later with 100 metacercariae and slaughtered 24 weeks postprimary infection. Skin eosinophil counts (SEC) were determined prior to infection on the basis of the intradermal reaction (IDR) to phytohaemagglutinin (PHA). These counts correlated negatively with the mean fluke length but not with the fluke burden found at necropsy. At the end of the experiment, non-specific (PHA) and specific (excretory-secretory parasite, products, FhESAg, and whole-worm extract, FhSomAg) immediate type hypersensitivity IDR were elicited in contrast to delayed type hypersensitivity (DTH) responses. The SEC correlated with blood eosinophilia but not with parasite parameters. These findings suggest that the eosinophil response does not correlate clearly with the development of resistance to F. hepatica infection in cattle. A specific mononuclear cell response to FhSomAg was detectable as early as 7 days after infection in both infected groups, being significantly higher during the very early migratory phase of the juveniles in the single-dose infected calves than in the trickle infected calves. This response remained significantly higher in infected groups than in the control group throughout the experiment. Challenge elicited a significant proliferative response, less pronounced than after primary infection. No production of gamma-interferon (INF-gamma) was recorded 3 weeks after challenge. At necropsy, the mean number of flukes recovered was similar in both infected groups, suggesting that the rate at which the infection is administrated has no effect on protective immunity. Hepatic lesions, similar in both infected groups, were characterised by marked eosinophil and mast-cell infiltration. Liver biopsies were performed and their diagnostic value is discussed. All results suggest that F. hepatica infection predominantly induces a Type-2 response in cattle, and that this response has little protective effect. [less ▲]

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See detailExtensive Genome-Wide Linkage Disequilibrium in Cattle
Farnir, Frédéric ULg; Coppieters, Wouter ULg; Arranz, J. J. et al

in Genome Research (2000), 10(2), 220-7

A genome-wide linkage disequilibrium (LD) map was generated using microsatellite genotypes (284 autosomal microsatellite loci) of 581 gametes sampled from the dutch black-and-white dairy cattle population ... [more ▼]

A genome-wide linkage disequilibrium (LD) map was generated using microsatellite genotypes (284 autosomal microsatellite loci) of 581 gametes sampled from the dutch black-and-white dairy cattle population. LD was measured between all marker pairs, both syntenic and nonsyntenic. Analysis of syntenic pairs revealed surprisingly high levels of LD that, although more pronounced for closely linked marker pairs, extended over several tens of centimorgan. In addition, significant gametic associations were also shown to be very common between nonsyntenic loci. Simulations using the known genealogies of the studied sample indicate that random drift alone is likely to account for most of the observed disequilibrium. No clear evidence was obtained for a direct effect of selection ("Bulmer effect"). The observation of long range disequilibrium between syntenic loci using low-density marker maps indicates that LD mapping has the potential to be very effective in livestock populations. The frequent occurrence of gametic associations between nonsyntenic loci, however, encourages the combined use of linkage and linkage disequilibrium methods to avoid false positive results when mapping genes in livestock. [less ▲]

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