Genomic characterisation, detection of genes encoding virulence factors and evaluation of antibiotic resistance of Trueperella pyogenes isolated from cattle with clinical metritis

Abstract

Trueperella pyogenes is one of the most important microorganisms causing metritis in post-partum cattle. Co-infection with other bacterial species such as Escherichia coli or Fusobacterium necrofurom increases the severity of the disease and the persistence of bacteria in utero. The aim of this study was to investigate the frequency of T. pyogenes strains, and their virulence and antimicrobial resistant profiles in metritis cases. The study was carried out on 200 samples obtained from metritis discharges of postpartum cattle on 18 farms around Tehran, Iran. Sixty-five T. pyogenes isolates (32.5%) were identified, of which 16 isolates were detected as pure cultures and the other 49 isolates from cultures most commonly mixed with E. coli or F. necrofurom. In terms of diversity in biochemical characteristic of T. pyogenes strains, 8 different biotypes were identified among the isolates. Single or multi antimicrobial resistance was observed in 48 isolates (73.9%), which was mostly against trimethoprim sulfamethoxazole, azithromycin, erythromycin and streptomycin. The tetracycline resistance gene tetW and macrolide resistance genes ermB and ermX were detected in 30, 18 and 25 isolates, respectively. In the screening of genes encoding virulence factors, fimA and plo genes were identified in all tested isolates. Genes encoding nanP, nanH, fimC, fimG, fimE and cbpA were detected in 50, 54, 45, 40, 50 and 37 of isolates, respectively. Thirteen different genotypes were observed in these T. pyogenes isolates. A significant association between clonal types and virulence factor genes, biochemical profile, CAMP test result, severity of the disease and sampling time was detected.

Infectious Agents Identified by Real-Time PCR, Serology and Bacteriology in Blood and Peritoneal Exudate Samples of Cows Affected by Parietal Fibrinous Peritonitis after Caesarean Section

“…Hence, it seems logical that exogenous contamination by T. pyogenes and E. coli during CS is a primary cause of infectious complications, including PFP and peritonitis [ 23 , 24 , 25 ]. Evidently, the risk of complications increases in the case of a massive contamination or immunosuppression [ 22 , 26 , 27 ]. On the other hand, since healthy cows can have a physiological bacteraemia [ 21 ], it is also plausible that PFP is the result of secondary haematogenous infection of a sterile fluid-filled cavity.…”

Pathogenicity and Virulence of Trueperella pyogenes: A Review

“…Interestingly, there were no relationships found between the virulence gene profiles of T. pyogenes strains and their origin, a type of infection and a host [13,21,29,30,31]. However, Ashrafi Tamai et al [32] reported a significant association between the virulence genotypes and clonal types of T. pyogenes isolates, and the severity of the clinical symptoms in postpartum cows with metritis.…”

Evaluation of the Potency of Two Pyolysin-Derived Recombinant Proteins as Vaccine Candidates of Trueperella Pyogenes in a Mouse Model: Pyolysin Oligomerization and Structural Change Affect the Efficacy of Pyolysin-Based Vaccines

“…Antibiotics, such as tylosin and tetracycline, are used to prevent liver abscess caused by bacteria such as T. pyogenes [2]. However, the emergence of drug-resistant bacterial strains restricted the use of antibiotics in food-producing animals [3][4][5]. Therefore, alternative methods for the prevention of T. pyogenes infections are still needed.…”