<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The aim was to investigate the antimicrobial susceptibility of most frequently isolated streptococci from Czech dairy herds. A total of 3,719 quarter milk samples were collected and cultivated between January 2017 and June 2018 from cows with clinical or subclinical mastitis from 112 farms. Only one isolate of each species, collected from the same farm per six-month period, was included in the susceptibility testing. The susceptibilities of <italic>Streptococcus uberis</italic> (163 isolates) and <italic>S. dysgalactiae</italic> (25 isolates) to 10 antimicrobials (penicillin – PEN, amoxicillin/clavulanic acid – AMC, ceftiofur – EFT, clindamycin – CLI, gentamicin – GEN, streptomycin – STR, trimethoprim/sulfamethoxazole – SXT, enrofloxacin – ENR, tetracycline – TET, rifampicin – RIF) from 9 groups were determined by measuring their minimum inhibitory concentrations. The percentages of resistant <italic>S. uberis</italic> isolates to the antimicrobials were as follows: TET (63.2%), STR (52.1%), CLI (30.1%), and RIF (2.5%). Intermediate susceptibility was found to RIF (63.2%), PEN (35%), ENR (2.5%), EFT (1.8%), and AMC (1.2%). All the <italic>S. uberis</italic> isolates were susceptible to GEN and SXT (100%). However, only 6.7% of <italic>S. uberis</italic> isolates were susceptible to all tested antimicrobials, and 38.7% of isolates were multidrug resistant (≥ 3 groups of antimicrobials). All the <italic>S. dysgalactiae</italic> isolates were susceptible to PEN, AMC, EFT, GEN, SXT, and ENR (100%). Resistant <italic>S. dysgalactiae</italic> isolates were found to TET (60%), STR (28%), CLI (12%), and intermediate to TET (24%) and RIF (20%). Sixteen percent of <italic>S. dysgalactiae</italic> isolates were multidrug resistant. The relatively high occurrence of (multiple) resistance, relative to mastitis pathogens, highlights the importance of monitoring this condition in dairy herds.</p></abstract>

The aim was to investigate the antimicrobial susceptibility of most frequently isolated streptococci from Czech dairy herds. A total of 3,719 quarter milk samples were collected and cultivated between January 2017 and June 2018 from cows with clinical or subclinical mastitis from 112 farms. Only one isolate of each species, collected from the same farm per six-month period, was included in the susceptibility testing. The susceptibilities of Streptococcus uberis (163 isolates) and S. dysgalactiae (25 isolates) to 10 antimicrobials (penicillin – PEN, amoxicillin/clavulanic acid – AMC, ceftiofur – EFT, clindamycin – CLI, gentamicin – GEN, streptomycin – STR, trimethoprim/sulfamethoxazole – SXT, enrofloxacin – ENR, tetracycline – TET, rifampicin – RIF) from 9 groups were determined by measuring their minimum inhibitory concentrations. The percentages of resistant S. uberis isolates to the antimicrobials were as follows: TET (63.2%), STR (52.1%), CLI (30.1%), and RIF (2.5%). Intermediate susceptibility was found to RIF (63.2%), PEN (35%), ENR (2.5%), EFT (1.8%), and AMC (1.2%). All the S. uberis isolates were susceptible to GEN and SXT (100%). However, only 6.7% of S. uberis isolates were susceptible to all tested antimicrobials, and 38.7% of isolates were multidrug resistant (≥ 3 groups of antimicrobials). All the S. dysgalactiae isolates were susceptible to PEN, AMC, EFT, GEN, SXT, and ENR (100%). Resistant S. dysgalactiae isolates were found to TET (60%), STR (28%), CLI (12%), and intermediate to TET (24%) and RIF (20%). Sixteen percent of S. dysgalactiae isolates were multidrug resistant. The relatively high occurrence of (multiple) resistance, relative to mastitis pathogens, highlights the importance of monitoring this condition in dairy herds.

Antimicrobial Susceptibility of Streptococci Most Frequently Isolated from Czech Dairy Cows with Mastitis

Department of Livestock Technology and Management

Department of Animal Genetics and Breeding

Annals of Animal Science

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The aim was to investigate the antimicrobial susceptibility of most frequently isolated streptococci from Czech dairy herds. A total of 3,719 quarter milk...

Antimicrobial Susceptibility of Streptococci Most Frequently Isolated from Czech Dairy Cows with Mastitis

Published Online: Jul 30, 2019

Page range: 679 - 694

Received: Oct 24, 2018

Accepted: Feb 11, 2019

DOI: https://doi.org/10.2478/aoas-2019-0015

Keywords
cattle, MIC, multiple resistance

© 2019 Soňa Šlosárková et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Antimicrobial Susceptibility of Streptococci Most Frequently Isolated from Czech Dairy Cows with Mastitis

Published Online: Jul 30, 2019

Page range: 679 - 694

Received: Oct 24, 2018

Accepted: Feb 11, 2019

DOI: https://doi.org/10.2478/aoas-2019-0015

Keywordscattle, MIC, multiple resistance

© 2019 Soňa Šlosárková et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
cattle, MIC, multiple resistance