Virulence Genes, Biofilm Production and Antibiotic Susceptibility in Trueperella pyogenes Isolated from Cattle

ABST RACT Trueperella pyogenes (formerly Arcanobacterium pyogenes) is a commensal bacterium present on the upper respiratory and urogenital tract mucosa of domestic and wild animals. It is also the most common opportunistic pathogen and isolated from the infections of cattle such as mastitis, metritis, arthritis and pneumonia. The aim of this study was to determine virulence genes (plo, nanH, nanP, cbpA, fimA, fimC, fimE, fimG) by polymerase chain reaction (PCR), biofilm production by modified microplate test and antibiotic susceptibilities by disc diffusion methods in 44 T. pyogenes isolated from various samples of cattle. Plo and fimA genes were detected in all isolates. CbpA, nanH, and nanP genes were determined in 6.8%, 61.3%, 84.1% of the isolates, respectively. FimC, fimE and fimG genes were found in 81.8%, 81.8% and 34.1% of the isolates, respectively. While all T. pyogenes isolates were found to be susceptible to amoxicillin-clavulanic acid, 97.7% were susceptible to cefoperazone, 95.45% to amoxicillin, ampicillin, florfenicol and penicillin and 75% to enrofloxacin and cloxacillin. Also all isolates were resistant to neomycin, 84.1% to oxytetracycline, 86.4% to gentamicin and 47.7% erythromycin. The majority of T. pyogenes isolates (88.6%) produced biofilms. In conclusion, this study reported that T. pyogenes might be a primary pathogen in mastitis, metritis, arthritis, pleuritis and abortion. The majority of T. pyogenes isolates had the capability to produce of biofilm that could result in difficulties in the treatment of T. pyogenes infections. Also the presence of genes encoded virulence factors may play important roles in the pathogenesis of the infections.