Aim: In this study, it was aimed to isolation and identification of Enterococcus durans and Enterococcus hirae which are frequently mixed with each other due to very high 16S rRNA similarity from mastitis cow milk samples and also to determine antibiotic resistance profiles of isolates.

Materials and Methods: The study material was consisted of 620 clinical or subclinical mastitis milk samples. Enterococci isolation was performed using conventional microbological methods and selective agars. Identifications based on genus and species were also confirmed by polymerase chain reaction (PCR). Resistance against to eight antimicrobial agents was investigated by the disk diffusion method.

Results: In the study 15.2% (94/620) Enterococcus spp. isolated; 9.6% (9/94) of them which were Enterococcus hirae and 5.3% (5/94) were Enterococcus durans. A total of 14 isolates were found to be susceptible to ampicillin, penicillin, vancomycin, ciprofloxacin and chloramphenicol. 57.1% (8/14), 42.9% (6/14) and 21.4% (3/14) were resistant to tetracycline, erythromycin and gentamycin, respectively.

Conclusion: It has been concluded that the polymerase chain reaction using species-specific primers is useful for the identification of frequently isolated enterococci from mastitic cattle milk samples. More attention should be paid to enterococci species other than Enterococcus faecalis and Enterococcus faecium and the monitoring of antimicrobial resistance should not be restricted to these two main species. Studies on the identification of virulence factors and antibiotic resistance genes of these two enterococci are thought to contribute to a better understanding of the pathogenesis of these microorganisms.