Research Article

Coagulase Negative Staphylococci as an emerging cause of bovine mastitis: prevalence, antimicrobial resistance and biofilm formation

Fawzy R. El-Seedy*, Ismail A. Radwan, Walid H. Hassan, Amr Shehata
Department of Bacteriology, Mycology and Immunology Faculty of Veterinary Medicine, Beni-Suef University, Beni-Suef 62511, Egypt

Abstract

Coagulase negative Staphylococci are the most prevalent cause of bovine subclinical mastitis. The current study were designed to study their occurrence, antibiogram and their ability to form biofilms. A total number of 95 CNS isolates were recovered from 400 lactating. S. xylosus (36.84%), S. chromogenes (12.63%), S. epidermidis (10.53%), S. saprophyticus (8.42%), S. haemolyticus (7.38%) were the most common recovered species. Disk diffusion method against 14 antimicrobials discs was used to detect their antibiogram. 100% were sensitive to Imipenem, 96.84% were sensitive to Enrofloxacin, 85.26% to Chlramphenicol and 84.21% to Vancomycin. But, 95.79% were resistant to Ampicillin, 77.9% resistant to Cefoxitin, 35.8% resistant to Cefuroxime, 32.63% resistant to Amoxycillin and 18.95% resistant to Clindamycin. Cultivation on Congo Red Agar (CRA) was carried out to detect biofilm formation. 47.37% were positive and S. epidermidis was the most biofilm positive species on CRA by the percentage of 70%. Haemolysins were studied by cultivating CNS on sheep blood agar. 25.26% were β-haemolytic, 71.57% (n=68) were γ- haemolytic and 3.15% were α- haemolytic.

Keywords

Coagulase Negative Staphylococci, Bovine Mastitis, Antimicrobial Resistance, Biofilm