@article{MAKHILLJAVA201110213076,
    title = {Laboratory Detection of <I>Haemophilus parasuis </I>with Decreased Susceptibility to Nalidixic Acid and Enrofloxacin Due to GyrA and ParC Mutations},
    journal = {Journal of Animal and Veterinary Advances},
    volume = {10},
    number = {21},
    pages = {2870-2873},
    year = {2011},
    issn = {1680-5593},
    doi = {javaa.2011.2870.2873},
    url = {https://makhillpublications.co/view-article.php?issn=1680-5593&doi=javaa.2011.2870.2873},
    author = {Pin,Yingyu,Chong,Haoyong,Yang,Wentao,Dingren and},
    keywords = {Detection,enrofloxacin,resistance,collection,nalidixic acid,China},
    abstract = {The detection of pathogens with decreased susceptibility to antibacterial and elucidating the molecular mechanism of resistance are of epidemiological and clinical interest in animal husbandry. The 21 <I>Haemophilus parasuis</I> clinical isolates and one American Type Culture Collection reference strains of <I>Actinobacillus pleuropneumoniae</I> (ATCC 27090) were screened for susceptibility to nalidixic acid and enrofloxacin by the microdilution methods. The nalidixic acid MICs for all of the isolates were &ge;2 &#956;g mL<SUP>-1</SUP> and the enrofloxacin MICs for isolates were &le;8 &#956;g mL<SUP>-1</SUP>. In addition, the Quinolone Resistance-Determining Regions (QRDRs) of gyrA and parC of all strains were sequenced. Strains for which nalidixic acid MICs were &le;4.0 &#956;g mL<SUP>-1</SUP> lacked modifications in the QRDRs of GyrA and ParC. In contrast, all strains for which nalidixic acid MICs were &ge;8 &#956;g mL<SUP>-1</SUP> exhibited one or more amino acid changes in GyrA and ParC. Mutations in GyrA is the major resistance mechanism of <I>Haemophilus parasuis</I> to nalidixic acid and enrofloxacin.}
    }