<abstract xmlns="http://www.w3.org/1999/xhtml"><p> Coagulase-positive staphylococci are the most common pathogen causing subclinical mastitis in cows. Their main characteristic is a high virulence which leads to chronic infection. A total of 213 isolates of coagulase-positive staphylococci were tested. The majority of isolates (58%) formed a gold pigment, then light gold (28%), white gold (8%), golden gray, creamy white and white (2%). The majority of isolated coagulase-positive staphylococci produce beta hemolysis on esculin blood agar (50%), alpha and beta hemolysis (36%), beta and delta hemolysis (8%), delta hemolysis (4%), and alpha hemolysis (2%). Biochemical and molecular identification was performed by APISTAPH and multiplex PCR method. The majority of isolates were identified as S. aureus (88%), S. chromogenes (4%), and 2% of the isolates were identified as S. lentus, S. sciuri, S. xylosus, S. intermedius by APISTAPH. Antimicrobial susceptibility to penicillin G, was found by the Kirby Bauer disk diffusion method to be resistant (62.44%). For disc diffusion penicillin G sensitive isolates the minimal inhibitory concentration (MIC) was established for MIC50 and MIC90 as 0.003 mg/ml and 2μg/ml, respectively. For disc diffusion penicillin G resistant isolates MIC50 and MIC90 was 1.0μg/ml and 16μg/ ml, respectively. The study of phenotypic resistance to methicillin, as recommended by CLSI, established resistance to oxacillin in 5.26% of the isolates, while no resistance was found to cefoxitine. None of the tested isolates have the mecA gene.</p></abstract>

Coagulase-positive staphylococci are the most common pathogen causing subclinical mastitis in cows. Their main characteristic is a high virulence which leads to chronic infection. A total of 213 isolates of coagulase-positive staphylococci were tested. The majority of isolates (58%) formed a gold pigment, then light gold (28%), white gold (8%), golden gray, creamy white and white (2%). The majority of isolated coagulase-positive staphylococci produce beta hemolysis on esculin blood agar (50%), alpha and beta hemolysis (36%), beta and delta hemolysis (8%), delta hemolysis (4%), and alpha hemolysis (2%). Biochemical and molecular identification was performed by APISTAPH and multiplex PCR method. The majority of isolates were identified as S. aureus (88%), S. chromogenes (4%), and 2% of the isolates were identified as S. lentus, S. sciuri, S. xylosus, S. intermedius by APISTAPH. Antimicrobial susceptibility to penicillin G, was found by the Kirby Bauer disk diffusion method to be resistant (62.44%). For disc diffusion penicillin G sensitive isolates the minimal inhibitory concentration (MIC) was established for MIC50 and MIC90 as 0.003 mg/ml and 2μg/ml, respectively. For disc diffusion penicillin G resistant isolates MIC50 and MIC90 was 1.0μg/ml and 16μg/ ml, respectively. The study of phenotypic resistance to methicillin, as recommended by CLSI, established resistance to oxacillin in 5.26% of the isolates, while no resistance was found to cefoxitine. None of the tested isolates have the mecA gene.

Characteristics of coagulase positive staphylococci isolated from milk in cases of subclinical mastitis

University of Belgrade, Faculty of Veterinary Medicine, Belgrade, Serbia;

Institute of Meat Hygiene and Technology, Belgrade, Serbia

Acta Veterinaria

Coagulase-positive staphylococci are the most common pathogen causing subclinical mastitis in cows. Their main characteristic is a high virulence which leads...

Characteristics of coagulase positive staphylococci isolated from milk in cases of subclinical mastitis

Published Online: Mar 25, 2014

Page range: 115 - 123

DOI: https://doi.org/10.2478/acve-2014-0012

Keywords
coagulase positive staphylococci, hemolysis, identification, methicillin, penicillin, pigment

This content is open access.

Characteristics of coagulase positive staphylococci isolated from milk in cases of subclinical mastitis

Published Online: Mar 25, 2014

Page range: 115 - 123

DOI: https://doi.org/10.2478/acve-2014-0012

Keywordscoagulase positive staphylococci, hemolysis, identification, methicillin, penicillin, pigment

This content is open access.

Keywords
coagulase positive staphylococci, hemolysis, identification, methicillin, penicillin, pigment