Relationships between antimicrobial resistance, distribution of virulence factor genes and the origin of Trueperella pyogenes isolated from domestic animals and European bison (Bison bonasus).

Trueperella pyogenes is an opportunistic pathogen causing suppurative infections in livestock and wild animals. Although this bacterium is known for a long time, our knowledge about its pathogenicity is still insufficient. In this study the relationships between antimicrobial resistance profiles, distribution of virulence factor genes and the origin of T. pyogenes isolates were investigated. Isolates (n = 97) from various infections in domestic animals and European bison were studied. Minimal inhibitory concentrations of 12 antimicrobials were determined by a strip diffusion method, and PCR was used for detection of genes encoding seven putative virulence factors. All strains were susceptible to tested beta-lactams, and a statistically significant correlation between the resistance to enrofloxacin, tetracycline, macrolides, clindamycin, and a strain origin was found. The isolates from European bison were more susceptible than those from livestock, however the resistance to tetracycline and fluoroquinolones was observed. The plo and fimA genes were detected in all strains. There was no statistically significant association between the distribution of particular virulence factor genes and the type of infection, but the nanH, nanP and fimG genes were less frequently found in the isolates from European bison. The presence of three genes, nanP, nanH and cbpA, was found to be related to the resistance to tetracycline and ciprofloxacin. In conclusion, the resistance patterns of T. pyogenes were correlated with an isolate origin, but our findings did not allow to indicate which of the putative virulence factors may play a crucial role in the pathogenesis of particular types of T. pyogenes infection.

Morbidity and mortality associated with Arcanobacterium pyogenes in a group of captive blackbuck (Antilope cervicapra).

Arcanobacterium pyogenes was associated with necrotizing pneumonia; mandibular osteomyelitis; peritonitis; and hepatic, pulmonary, renal, and subcutaneous abscessation in a group of captive blackbuck (Antilope cervicapra). Males were more frequently (73.3%) affected than females. Infection with A. pyogenes was fatal or necessitated euthanasia in 15 of 16 (93.7%) cases. Deaths associated with A. pyogenes occurred most frequently (60%) during winter.

The gene encoding pyolysin, the pore-forming toxin of Arcanobacterium pyogenes, resides within a genomic islet flanked by essential genes.

The plo gene, encoding the Arcanobacterium pyogenes cholesterol-dependent cytolysin, pyolysin (PLO), was localized to a 2.7-kb genomic islet of reduced %G+C content and alternate codon usage frequency. This islet, conserved among isolates from diverse hosts and geographical locations, separated the housekeeping genes smc and ftsY, which are found adjacent in many prokaryotes. The ftsY and ffh genes, located downstream of the plo islet, encode components of the signal recognition particle. Mutational analysis suggested that these genes were essential for viability in A. pyogenes. The A. pyogenes ffh gene was unable to complement a conditional ffh mutant of Escherichia coli and its overexpression was toxic in E. coli. Mutagenesis of the islet-encoded orf121 did not affect plo expression, indicating that it may not be involved directly in the regulation of plo expression. Regardless, the presence of the plo gene as part of a genomic islet inserted between genes essential for normal growth may provide selective pressure for the retention of this important virulence factor.

Corynebacterium pyogenes. Its pathogenic mechanism in epidemic leg ulcers in Thailand.

There is a yearly outbreak of endemic leg ulcers in Thailand. Corynebacterium pyogenes, a pathogen to animals, is frequently isolated from the fresh lesions in addition to common pyogenic bacteria such as beta-hemolytic streptococci, mostly group A, and Staphylococcus aureus and Staphylococcus epidermidis. Although circulating titers of IgG and IgM anti-C. pyogenes antibodies were found to be very low in studied cases, intradermal skin test with C. pyogenes vaccine containing nonviable 10(5) microorganisms induced an erythematous reaction with maximum intensity at 6 hours; direct immunofluorescence showed granular deposition of C3 along the dermoepidermal junction at this time. Unexpectedly, the sites of such a skin test that subsequently underwent biopsy presented tender erythematosus induration 1 week later and developed granulomatous ulcerative lesions after 10 days in 11 of 15 patients. Radioimmunoassay for C5a and C5a of arginine demonstrated that C. pyogenes activated complement even in the absence of specific antibodies. These findings suggest that importance of skin injury followed by infection with C. pyogenes in the development of endemic leg ulcers, supporting our hypothesis that the infection of accidentally traumatized skin by C. pyogenes, which is carried by Oriental-eye flies, induces the granulomatous lesions of endemic leg ulcers.

[Experimental induction of foot rot in sheep]. / Eksperimentalno predizvikane na kopiten gnilets po ovtsete.

By means of local strains Bacteroides nodusus was reproduced experimentally a case of foot-rot with sheep. For the appearance and the development of the disease it was necessary, before the infection, to keep the sheep in damp and uncleaned from fecal impurities room. Besides that, of decisive importance was the scarification of the skin-horny junction in the interungular slit. The combination of Bacteroides nodusus with Spirohaeta penorta and Corynebacterium piogenes resulted in more serious changes in the infected hooves.

[Clinical and experimental studies of suppurative surgical infection in cattle]. / Klinichno-eksperimentalni prouchvaniia na gnoinata khirurgischeska infektsiia u govedoto.

Investigated were a total of 30 cattle 6 of which had experimental surgery infection and 24 showed spontaneously developing suppurative infection. The animals were studied in terms of general status, blood picture, quality of urine and synovia, and rumen content. The dynamis was followed up of the development of sepsis and purulent artritis. It was found that in case of suppurative surgical infections in cattle the general status was invariably affected, the severity of the process depending on its localization and developmental phase. Changes were observed also in the eye fundus and in the urinary and the digestive system. There were anemia and leukopenia which alternated with leukocytosis, and transient changes in the values of the erythrocyte sedimentation rate and the blood electrolytes. The SGOT values almost constantly increased, and the hemoculture was not positive in all cases.