Detection of peste des petits ruminants virus in formalin-fixed tissues

Evaluation of a Method for Standardized Antimicrobial Susceptibility Testing with Mycoplasma hyorhinis Field Isolates

Organizations like the Clinical and Laboratory Standards Institute (CLSI) or the European Committee of Antimicrobial Susceptibility Testing (EUCAST) provide standardized methodologies for antimicrobial susceptibility testing of a wide range of nonfastidious and fastidious bacteria, but so far not for Mycoplasma spp. of animal origin. Recently, a proposed method for the standardized broth microdilution testing of Mycoplasma hyorhinis using commercial Sensititre microtiter plates was presented. In this study, we evaluated this broth microdilution method with 37 field isolates and tested their susceptibility toward the following antimicrobial agents: doxycycline, enrofloxacin, erythromycin, florfenicol, gentamicin, marbofloxacin, tetracycline, tiamulin, tilmicosin, tulathromycin, and tylosin. The isolates originated from different countries, isolation sites, and years. The broth microdilution method was carried out using a modified Friis broth as the culture and test medium. For macrolides and lincosamides, a bimodal distribution with elevated MIC values could be observed for almost half of the tested field isolates, deducing reduced susceptibility toward these substances. With a recently published protocol, we were able to test a variety of field isolates, and consistent data could be obtained. Using this method, monitoring studies of Mycoplasma hyorhinis isolates can be carried out in a comparable manner, and the observed susceptibility profiles can be screened for possible changes in MIC values in the future.

Confirmation and Sequence analysis of N gene of PPRV in South Xinjiang, China

ABSTRACT In China, Peste des petits ruminants (PPR) was officially first reported in 2007. From 2010 until the outbreak of 2013, PPRV infection was not reported. In November 2013, PPRV re-emerged in Xinjiang and rapidly spread to 22 P/A/M (provinces, autonomous regions and municipalities) of China. In the study, suspected PPRV-infected sheep in a breeding farm of South Xinjiang in 2014 were diagnosed and the characteristics of complete sequence of N protein gene of PPRV was analyzed. The sheep showed PPRV-infected signs, such as fever, orinasal secretions increase, dyspnea and diarrhea, with 60% of morbidity and 21.1% of fatality rate. The macroscopic lesions after autopsy and histopathological changes were observed under light microscope including stomatitis, broncho-interstitial pneumonia, catarrhal hemorrhagic enteritis and intracytoplasmic eosinophilic inclusions in multinucleated giantcell in lung. The formalin-fixed mixed tissues samples were positive by nucleic acid extraction and RT-PCR detection. The nucleotide of N protein gene of China/XJNJ/2014 strain was extremely high homology with the China/XJYL/2013 strain, and the highest with PRADESH_95 strain from India in exotic strains. Phylogenetic analysis based on complete sequence of N protein gene of PPRV showed that the China/XJNJ/2014 strain, other strain of 2013-2014 in this study and Tibetan strains all belonged to lineage Ⅳ, but the PPRV strains of 2013-2014 in this study and Tibetan strains were in different sub-branches.