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In this retrospective study, it was evaluated the antimicrobial susceptibility profiles of Bacillus anthracis isolates obtained from human, various samples (blood, spleen, lung, liver, meat) of dead animals (cattle, sheep, dog, horse) that died from anthrax and soil samples from the animal burial areas between 2012 and 2023 from Kars province of Türkiye. In this context, a total of 87 B. anthracis isolates obtained from 1 human, two horses, 51 cattle, 7 sheep, 1 dog, and 25 soil were investigated. The isolates were confirmed as B. anthracis using protective antigen (PA) and capsule (Cap) gen specific PCRs. The Kirby-Bauer disk diffusion method was used for deternination of antimicrobial susceptibility. Ten antimicrobials including penicillin, amoxicillin, trimethoprim-sulfometoxazole, erythromycin, meropenem, streptomycin, ofloxacin, ciprofloxacin, chloramphenicol, and clindamycin were tested. As a result of PCR, all isolates were confirmed as fully virulent field strains of B. anthracis. All isolates were found as susceptible to penicillin, amoxicillin, ofloxacin and ciprofloxacin. Since the last studies in the region, a change in the antimicrobial profile of B. anthracis strains was observed only for trimethoprim-sulfomethoxazole among the antimicrobials tested, a transition from susceptibility to resistance. In conclusion, penicillin and amoxicillin, are still the antibiotic of first choice for the prophylaxis and treatment of anthrax. Ofloxacin and ciprofloxacin are also effective enough to be prescribed for treatment. [ABSTRACT FROM AUTHOR]

Among the heterogeneous Pasteurellaceae family, Pasteurella multocida and Mannheimia haemolytica are the pathogenic species that cause enzootic pneumonia in cattle and sheep. This study was designed to characterize Pasteurella and Mannheimia species obtained from pneumonia cases in cattle and sheep. The lungs of 100 cattle and 100 sheep diagnosed with infectious pneumonia as a result of histopathological examination were analyzed for Pasteurellaceae members by phenotypic methods, the VITEK 2 Compact system (VITEK), and polymerase chain reaction (PCR). Antibiotic susceptibilities and phylogenetic analysis of the isolates were done by VITEK and 16S rRNA-PCR, respectively. Seven Pasteurella multocida and 9 Mannheimia haemolytica were identified. All strains were resistant to ampicillin and trimethoprim/sulfamethoxazole. High susceptibility to ceftiofur (100%, 7/7 and 88.89%, 8/9) and doxycycline (85.71%, 6/7 and 100%, 9/9) was detected among the P. multocida and M. haemolytica isolates, respectively. The minimum inhibitory concentration (MIC) for gentamicin was within the epidemiologic cutoff limits. The diversity of resistance genes (TEM, OXA-58, AadB, AadA25, Tet H, and Sul 2) was high and their frequency ranged from 22.22% to 100% (16/16) among the strains. Multidrug resistance (MDR) was detected as 100% (7/7) for P. multocida and 33.33% (3/9) for M. haemolytica strains. Based on the MDR, six resistotypes (A to F) were determined, with more among the P. multocida strains. An approach called 'antibiotic resistance marker-based genotyping' was introduced based on the presence of antibiotic resistance genes, and 8 genotypes (I to VIII) were determined, with more profiles (I to V) among the P. multocida strains. The 16S rRNA gene sequencing positioned the strains in two main phylogenetic clusters, and P. multocida strains were found to be more genetically close. A better understanding of bacterial behaviors related to antimicrobial susceptibility may aid communication with producers and veterinarians regarding appropriate antimicrobial stewardship. Phylogenetic clustering of strains can increase country-specific sequence data and create new taxa from a universal perspective. [ABSTRACT FROM AUTHOR]

Campylobacter jejuni is a causative agent of gastroenteritis in humans worldwide, and wild and domestic poultry carry of this bacterium in their gastrointestinal tract. Molecular studies to determine the pathogenicity, origin, and epidemiological relationships among C. jejuni isolates from poultry such as chicken, turkey, and goose consumed as human food are important for public health and infection control. This study aimed to investigate the prevalence of virulence genes and Enterobacterial Repetitive Intergenic Consensus (ERIC‐PCR) based genotyping of C. jejuni isolates obtained from goose cloacal swab samples. For this purpose, PCR analysis of flaA, racR, dnaJ, pldA, cadF, cdtC, ciaB, cdtB, cdtA, virB11, and wlaN virulence genes and ERIC‐PCR analysis of 50 C. jejuni isolates were performed. The emerged genetic profiles and antimicrobial resistance genes regarding the isolates were interpreted with the existing multi‐drug resistance (MDR) findings. Virulence gene positivity was detected as 88%, 84%, 82%, 82%, 80%, 80%, 72%, 30%, and 18% for flaA, racR, dnaJ, pldA, cadF, cdtC, ciaB, cdtB, and cdtA, respectively. VirB11 and wlaN genes were not detected among the C. jejuni isolates. Virulence genes‐based genotyping revealed that the C. jejuni isolates exhibited 22 profiles (A–V). As a result of ERIC‐PCR analysis, the C. jejuni isolates showed heterogeneous distribution, exhibiting 14 different ERIC‐PCR profiles (Cluster I [Cl‐I]–Cluster XIV [Cl‐XIV]). The MDR positivity was detected in 7 (14%) of the C. jejuni isolates. Tetracycline and ciprofloxacin were the antibiotics most frequently included in the MDR profiles. There was no clear correlation between ERIC‐PCR profiles, virulence gene profiles, and MDR profiles. However, isolates with triple‐MDR resistant to ampicillin, tetracycline, and ciprofloxacin showed significant heterogeneity in both ERIC‐PCR profile and virulence gene‐based genetic profile, all of which were positive for ciaB and flaA genes. These results indicate that carriage of the C. jejuni isolates with high gene prevalence and MDR profiles by geese may pose a risk for Campylobacter infections in humans. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate Brucella spp. isolated from various tissue samples of aborted sheep and bovine fetuses sent to the laboratory of Department of Microbiology, Faculty of Veterinary Medicine, Kafkas University between 2011 and 2023 years and determine the Brucella species and biotype diversity that carry a higher risk for abortion complications in these animals. In this context, 155 Brucella spp. isolates obtained from aborted fetuses were identified by species-specific Bruceladder PCR and biotyped using conventional biotyping methods. As a result of the study, B. melitensis and B. abortus were identified in 92.5% (n=74) and 7.5% (n=6) of sheep, B. abortus and B. melitensis were identified in 80% (n=60) and 20% (n=15) of cattle, respectively. B. melitensis biotype 2 in sheep and B. abortus biotype 3 in cattle were found as the dominant biotypes in these definitive hosts. In the Kars region, where brucellosis is endemic, while the biotype responsible for cattle brucellosis (B. abortus biotype 3) maintained its dominance over a 20-year period, there is a profile change from B. melitensis biotype 3 to B. melitensis biotype 2 in sheep. Considering the period covered by the study and the sample size analyzed, the data obtained provide up-to-date and important information about Brucella species and biotypes in Kars region and the animal species that host these agents. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the chemical composition and antimicrobial activity of laurel leaf extracts obtained using different methods and solvents. Extraction was performed using the Soxhlet, ultrasound-assisted, and orbital shaker methods with water, ethanol, methanol, ethyl acetate, acetone, hexane and chloroform. The chemical compositions of the extracts were analyzed with a gas chromatograph coupled to a mass spectrometer and a flame ionization detector (GC-MS-FID). The GC-MS-FID results were compared to data of the Wiley and National Institute of Standards and Technology (NIST) libraries to identify the chemical composition of the analytes. The antimicrobial activities of the extracts against Staphylococcus aureus NCTC10788, Bacillus cereus NCTC7464, Salmonella typhi NCTC11994, Listeria monocytogenes ATCC11994 and Escherichia coli NCTC2001 were determined with in-house disc diffusion testing. The highest efficiency was achieved using the Soxhlet method and methanol (49.11%). Among the solvents tested, hexane, and among the methods used, ultrasound-assisted extraction exhibited the lowest efficiency (P<0.05). The extracts showed a stronger inhibitory effect on Grampositive bacteria (P<0.05). The highest level of antimicrobial activity was achieved against S. aureus with the use of the stock solution concentrations of the extracts obtained with the combined use of the ultrasound-assisted method and the solvents ethanol, ethyl acetate, acetone and hexane. The bacteria most resistant to almost all concentrations of the laurel leaf extracts were S. typhi, E. coli and L. monocytogenes. The method and solvent for extraction should be chosen carefully, depending on the targeted molecules and desired activity. [ABSTRACT FROM AUTHOR]