Experimental infection of SPF pigs with Actinobacillus pleuropneumoniae serotype 9 alone or in association with Mycoplasma hyopneumoniae     

Marois C  Gottschalk M  Morvan H  Fablet C  Madec F  Kobisch M 《Veterinary microbiology》2009,135(3-4):283-291

The purpose of this study was to compare in SPF pigs, the pathogenicity of an Actinobacillus pleuropneumoniae serotype 9 strain 21 (isolated from the palatine tonsils of a healthy gilt on a French nucleus pig farm, with no clinical signs or lung lesions but a highly positive reaction to A. pleuropneumoniae serotype 9 antibodies) with a pathogenic A. pleuropneumoniae strain 4915 serotype 9 (isolated in France from an outbreak of porcine pleuropneumonia). The pathogenicity of one Mycoplasma hyopneumoniae strain alone or associated with A. pleuropneumoniae strain 21 was also compared. Eight groups of 7 pigs were infected (at 6 or 10 weeks of age) and a control group was kept non-infected. Results showed that sensitivity to A. pleuropneumoniae was related to the age of the pig (6 weeks vs 10 weeks) whatever the strain. Surviving pigs infected at 6 weeks of age developed severe clinical signs, lung lesions typical of A. pleuropneumoniae and they seroconverted. In contrast, symptoms and lung lesions were almost non-existent in pigs infected with strain 21 at 10 weeks of age, but a seroconversion was observed with very high ELISA titres. These results were in accordance with those observed in the nucleus pig farm. Infection with M. hyopneumoniae alone induced typical mycoplasmal symptoms, pneumonia and seroconversion. Symptoms and lung lesions were the most noticeable in pigs infected with M. hyopneumoniae at 6 weeks of age and with A. pleuropneumoniae 4 weeks later. Our results show that the presence of A. pleuropneumoniae serotype 9 in a pig herd may be clinically unnoticed and that M. hyopneumoniae may potentiate A. pleuropneumoniae infection.  相似文献   

Effect of solar radiation on severity of soybean rust     

Young HM  George S  Narváez DF  Srivastava P  Schuerger AC  Wright DL  Marois JJ 《Phytopathology》2012,102(8):794-803

Soybean rust (SBR), caused by Phakopsora pachyrhizi, is a damaging fungal disease of soybean (Glycine max). Although solar radiation can reduce SBR urediniospore survival, limited information is available on how solar radiation affects SBR progress within soybean canopies. Such information can aid in developing accurate SBR prediction models. To manipulate light penetration into soybean canopies, structures of shade cloth attenuating 30, 40, and 60% sunlight were constructed over soybean plots. In each plot, weekly evaluations of severity in lower, middle, and upper canopies, and daily temperature and relative humidity were recorded. Final plant height and leaf area index were also recorded for each plot. The correlation between amount of epicuticular wax and susceptibility of leaves in the lower, middle, and upper canopies was assessed with a detached leaf assay. Final disease severity was 46 to 150% greater in the lower canopy of all plots and in the middle canopy of 40 and 60% shaded plots. While daytime temperature within the canopy of nonshaded soybean was greater than shaded soybean by 2 to 3°C, temperatures recorded throughout typical evenings and mornings of the growing season in all treatments were within the range (10 to 28.5°C) for SBR development as was relative humidity. This indicates temperature and relative humidity were not limiting factors in this experiment. Epicuticular wax and disease severity in detached leaf assays from the upper canopy had significant negative correlation (P = 0.009, R = -0.84) regardless of shade treatment. In laboratory experiments, increasing simulated total solar radiation (UVA, UVB, and PAR) from 0.15 to 11.66 MJ m(-2) increased mortality of urediniospores from 2 to 91%. Variability in disease development across canopy heights in early planted soybean may be attributed to the effects of solar radiation not only on urediniospore viability, but also on plant height, leaf area index, and epicuticular wax, which influence disease development of SBR. These results provide an understanding of the effect solar radiation has on the progression of SBR within the soybean canopy.  相似文献   

Prevalence of Parascaris equorum infection in foals on French stud farms and first report of ivermectin-resistant P. equorum populations in France     

Laugier C  Sevin C  Ménard S  Maillard K 《Veterinary parasitology》2012,188(1-2):185-189

  相似文献   

Correlation between the serum neutralization test and the indirect immunofluorescent test for the detection of specific antibodies to infectious bovine rhinotracheitis virus.          下载免费PDF全文

R Assaf  G Marsolais  P Marois    P Payment 《Canadian journal of veterinary research》1975,39(2):224-226

Comparative titrations show that immunofluorescence on infected rabbit kidney cells is relatively as sensitive as the neutralization test for the detection of antibodies to the infectious bovine rhinotracheitis virus. When calf testis cells infected with this virus are used for the detection of antibodies by the indirect immunofluorescent test nonspecific staining is high. This nonspecific reaction is absent when rabbit kidney cells are used.  相似文献   

HAEMOLYTIC DISEASE OF THE NEWBORN IN CALVES   总被引：1，自引：0，他引：1  

Corinne K. Dimmock  K. Bell 《Australian veterinary journal》1970,46(2):44-47

  相似文献   

Foal IgG and opsonizing anti-Rhodococcus equi antibodies after immunization of pregnant mares with a protective VapA candidate vaccine     

Cauchard J  Sevin C  Ballet JJ  Taouji S 《Veterinary microbiology》2004,104(1-2):73-81

The aim of this study was to evaluate serum IgG antibody levels and opsonizing activity in foals from pregnant mares immunized with either proteins from an R. equi strain containing virulence-associated protein A (VapA), an immunodominant surface-expressed lipoprotein encoded by a virulence plasmid crucial for virulence in foals, or a whole killed virulent R. equi preparation. Forty-eight pregnant mares were distributed into three groups, i.e. 24 immunized with R. equi VapA protein antigen associated with a water-based nanoparticle adjuvant (Montanide IMS 3012), 8 immunized with whole killed R. equi, and 16 non-immunized as control. Serum IgG and opsonizing capacity were evaluated during pregnancy in mares, and up to day 45 post-delivery in foals in which R. equi infections were recorded in the first 6 months of life. Pregnant mares immunized with virulent R. equi proteins developed higher serum IgG and opsonic activity which were transferred to the foals than either in the whole R. equi immunized or the control group. Four foals developed pneumonia in the control group while none in immunized groups. Results support further evaluation of VapA protein antigen associated with a water-based nanoparticle adjuvant as a candidate vaccine for immunization of pregnant mares resulting in passive antibody-mediated protection of foals.  相似文献   

Expressed sequence tags from the phytopathogenic fungus Botrytis cinerea     

Muriel Viaud  Fabrice Legeai  Jean-Marc Pradier  Yves Brygoo  Frédérique Bitton  Jean Weissenbach  Adeline Brunet-Simon  Aymeric Duclert  Sabine Fillinger  Dominique Fortini  Anastasia Gioti  Corinne Giraud  Sébastien Halary  Isabelle Lebrun  Pascal Le Pêcheur  Delphine Samson  Caroline Levis 《European journal of plant pathology / European Foundation for Plant Pathology》2005,111(2):139-146

A large set of genes was identified in the phytopathogenic fungus Botrytis cinerea by using an expressed sequence tag approach. The fungus was grown in axenic culture and a cDNA library was produced. From this library, 6559 ESTs were obtained. The combined sequences represent 3026 unisequences that corresponds to approximately one-quarter of the estimated total number of genes in B. cinerea. Approximately 18% of the ESTs showed significant similarities with genes coding for proteins with known functions,~56% were similar to genes coding for proteins with unknown functions and ~26% were orphans. A substantial B. cinerea gene inventory including putative virulence factors was therefore obtained and is now available at the Génoplante-Info Database interface (http://urgi.infobiogen.fr///Projects/GPiDB/Interface/).  相似文献   

Colony Husbandry of the Monkey          下载免费PDF全文

P. Marois  G. Boulay    E. di Franco 《Canadian journal of veterinary research》1961,25(11):291-295

  相似文献   

Streptococcus equi infections in horses: guidelines for treatment, control, and prevention of strangles     

Sweeney CR  Timoney JF  Newton JR  Hines MT 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(1):123-134

  相似文献   

Maladies procines à étiologie virale dans la province de Québec. I. Influenza          下载免费PDF全文

A N Gagnon  A Boudreault  G Marsolais  G Lussier    P Marois 《The Canadian veterinary journal. La revue veterinaire canadienne》1974,15(11):312-315

  相似文献