Prevalence Study of Biofilm Marker ica D Gene among Coagulase Positive Staphylococcus of Mastitic Origin

ABSTRACT: Bovine Mastitis is an inflammation of the mammary gland, usually due to microbial infection, which causes economic loss to dairy producer every year. Staphylococcus is one of the most common pathogens responsible for contagious mastitis in bovines. The aim of this study was to identify coagulase positive Staphylococci isolated from bovine subclinical mastitis. In vitro biofilm forming ability of the isolates, an important virulence factor of mastitogen and prevalence of biofilm marker icaD gene among the isolates. In the present study, 70 isolates were biochemically identified as S. aureus. Biochemically characterized strains of S. aureus were screened for biofilm formation. Phenotypic detection of biofilm formation of S.aureus were done by two methods, namely, Congo Red Agar (CRA) method and Tube Method (TM). The frequency of biofilm formation in S. aureus strains was 28.57 per cent on CRA plates while 71.42 per cent were biofilm non-producers. The frequency of biofilm formation in S. aureus strains was 38.57 per cent in total as shown by tube method while 61.42 per cent were biofilm non-producers. Employing PCR, molecular detection technique of icaD gene was carried out. In this study, 72.85 per cent S. aureus strains were found to be positive for icaD gene which produced an amplicon of 381bp