scholarly journals Sequence characterisation and novel insights into bovine mastitis-associated Streptococcus uberis in dairy herds

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ben Vezina ◽  
Hulayyil Al-harbi ◽  
Hena R. Ramay ◽  
Martin Soust ◽  
Robert J. Moore ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Resistance Genes ◽  
Bovine Mastitis ◽  
Antibiotic Resistance Genes ◽  
Mammary Tissue ◽  
Putative Virulence Factor ◽  
Disease Pathogenesis ◽  
Streptococcus Uberis ◽  
Genome Phylogeny ◽  
Geographic Regions

AbstractStreptococcus uberis is one of the most frequent mastitis-causing pathogens isolated from dairy cows. Further understanding of S. uberis genetics may help elucidate the disease pathogenesis. We compared the genomes of S. uberis isolates cultured from dairy cows located in distinctly different geographic regions of Australia. All isolates had novel multi locus sequence types (MLST) indicating a highly diverse population of S. uberis. Global clonal complexes (GCC) were more conserved. GCC ST86 and GCC ST143 represented 30% of the total isolates (n = 27) and were clustered within different geographic regions. Core genome phylogeny revealed low phylogenetic clustering by region, isolation source, and MLST. Identification of putative sortase (srtA) substrates and generation of a custom putative virulence factor database revealed genes which may explain the affinity of S. uberis for mammary tissue, evasion of antimicrobial efforts and disease pathogenesis. Of 27 isolates, four contained antibiotic resistance genes including an antimicrobial resistance cluster containing mel/mef(A), mrsE, vatD, lnuD, and transposon-mediated lnuC was also identified. These are novel genes for S. uberis, which suggests interspecies lateral gene transfer. The presence of resistance genes across the two geographic regions tested within one country supports the need for a careful, tailored, implementation and monitoring of antimicrobial stewardship.

scholarly journals Phenotypic and molecular characterization of antimicrobial resistance in Trueperella pyogenes strains isolated from bovine mastitis and metritis

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Mobin Rezanejad ◽  
Sepideh Karimi ◽  
Hassan Momtaz
Keyword(s):  
Antibiotic Resistance ◽  
Antimicrobial Resistance ◽  
Dairy Cows ◽  
Virulence Factors ◽  
Resistance Genes ◽  
Bovine Mastitis ◽  
Antibiotic Resistance Genes ◽  
Trueperella Pyogenes ◽  
Mastitic Milk

Abstract Background Trueperella pyogenes is one of the most clinically imperative bacteria responsible for severe cases of mastitis and metritis, particularly in postpartum dairy cows. The bacterium has emergence of antibiotic resistance and virulence characters. The existing research was done to apprise the phenotypic and genotypic evaluation of antibiotic resistance and characterization of virulence factors in the T. pyogenes bacteria of bovine mastitis and metritis in postpartum cows. Methods Two-hundred and twenty-six bovine mastitic milk and 172 uterine swabs were collected and transferred to laboratory. Samples were cultured and T. pyogenes isolates were subjected to disk diffusion and DNA extraction. Distribution of virulence and antibiotic resistance genes was studied by PCR. Results Thirty-two out of 226 (14.15%) mastitic milk and forty-one out of 172 (23.83%) uterine swab samples were positive for T. pyogenes. Isolates of mastitic milk harbored the highest prevalence of resistance toward gentamicin (100%), penicillin (100%), ampicillin (90.62%), amoxicillin (87.50%) and trimethoprim-sulfamethoxazole (87.50%), while those of metritis harbored the highest prevalence of resistance toward ampicillin (100%), amoxicillin (100%), gentamicin (97.56%), penicillin (97.56%) and cefalexin (97.56%). AacC, aadA1, aadA2 and tetW were the most generally perceived antibiotic resistance genes. All bacteria harbored plo (100%) and fimA (100%) virulence factors. NanP, nanH, fimC and fimE were also the most generally perceived virulence factors. Conclusions All bacteria harbored plo and fimA virulence factors which showed that they can use as specific genetic markers with their important roles in pathogenicity of T. pyogenes bacteria. Phenotypic pattern of antibiotic resistance was confirmed by genotypic characterization of antibiotic resistance genes.

scholarly journals Study ofStaphylococcus aureuscollected at slaughter from dairy cows with chronic mastitis

2012 ◽  
Vol 79 (2) ◽  
pp. 249-255 ◽  
Author(s):  
Renata Piccinini ◽  
Riccardo Tassi ◽  
Valentina Daprà ◽  
Rachel Pilla ◽  
Jackie Fenner ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Gel Electrophoresis ◽  
Bovine Mastitis ◽  
Pulsed Field Gel Electrophoresis ◽  
Mammary Tissue ◽  
Molecular Characteristics ◽  
Dairy Herds ◽  
Staph Aureus ◽  
Pfge Profiles

Staphylococcus aureusis one of the most important pathogens associated with bovine mastitis. Recent studies have shown thatStaph. aureusstrains may differ in virulence, and in their ability to disseminate across commercial dairy herds. The goal of this study was to determine whetherStaph. aureusisolates differed in their ability to colonize mammary tissue, and whether such differences could be related to molecular characteristics. Quarter milk and mammary tissues of 22 cows from two dairy herds, were collected at slaughter and bacteriological analysis was performed. AllStaph. aureusisolates were characterized by Pulsed Field Gel Electrophoresis (PFGE) and microarray. Overall 45 mammary quarters were infected and 20Staph. aureusisolates were identified. The bacteria were mostly recovered from both milk and tissue of the same quarter in significantly higher numbers from herd A cows compared with herd B. Molecular characterization of the isolates showed distinct PFGE profiles for isolates from each herd. Differences in virulence factors between herds A and B isolates were evidenced The genes for enterotoxin D, J and R were present in herd A, those for G, I, N, M, O and U were shown in herd B, whilst both components of the leukocidinlukD/Egenes were only carried by herd A isolates. Furthermore, all herd A isolates showed β-haemolysin activity, which was absent in all but one isolate from herd B. Therefore our data indicate thatStaph. aureusisolates showing differences in their ability to disseminate and colonize across quarters, also have significantly different virulence characteristics.

scholarly journals Antibiogram and Antibiotic Resistance Genes among Coagulase-Negative Staphylococci recovered from Bovine Mastitis

2021 ◽  
Vol 9 (8) ◽  
Author(s):  
Mousa S. Walid ◽  
Akram A. Salama ◽  
Shimaa S. Elnahriry ◽  
Eman E. Abdeen ◽  
Ghada Abd Elmonsef Hadad ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Bovine Mastitis ◽  
Antibiotic Resistance Genes ◽  
Coagulase Negative Staphylococci

Quintuplex PCR to Detect Antibiotic Resistance Genes in Streptococcus pneumoniae

2016 ◽  
Vol 1 (2) ◽  
pp. 22 ◽  
Author(s):  
Navindra Kumari Palanisamy ◽  
Parasakthi Navaratnam ◽  
Shamala Devi Sekaran
Keyword(s):  
Antibiotic Resistance ◽  
Streptococcus Pneumoniae ◽  
Resistance Genes ◽  
Bacterial Pathogen ◽  
Antibiotic Resistance Genes ◽  
Pcr Amplification ◽  
Penicillin Resistance ◽  
Penicillin Binding Proteins ◽  
Efflux Mechanism ◽  
Mic Value

Introduction: Streptococcus pneumoniae is an important bacterial pathogen, causing respiratory infection. Penicillin resistance in S. pneumoniae is associated with alterations in the penicillin binding proteins, while resistance to macrolides is conferred either by the modification of the ribosomal target site or efflux mechanism. This study aimed to characterize S. pneumoniae and its antibiotic resistance genes using 2 sets of multiplex PCRs. Methods: A quintuplex and triplex PCR was used to characterize the pbp1A, ermB, gyrA, ply, and the mefE genes. Fifty-eight penicillin sensitive strains (PSSP), 36 penicillin intermediate strains (PISP) and 26 penicillin resistance strains (PRSP) were used. Results: Alteration in pbp1A was only observed in PISP and PRSP strains, while PCR amplification of the ermB or mefE was observed only in strains with reduced susceptibility to erythromycin. The assay was found to be sensitive as simulated blood cultures showed the lowest level of detection to be 10cfu. Conclusions: As predicted, the assay was able to differentiate penicillin susceptible from the non-susceptible strains based on the detection of the pbp1A gene, which correlated with the MIC value of the strains.

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