Detection of Biofilm Forming Ability of Staphylococci Causing Bovine Mastitis Using Phenotypic and Genotypic Assays

Staphylococcus spp. is one of the most common pathogens responsible for contagious mastitis in bovines. The ability of Staphylococcus to form biofilm in vivo is considered to be a major virulence factor influencing its pathogenesis in mastitis. A total of 300 milk samples from cows and buffaloes were screened for mastitis and 47 Staphylococcus were identified from these samples. For the detection of Biofilm formation in isolates of Staphylococcus, phenotypically, Tube method (TM) and Congo Red Agar method (CRA) were used. The presence of the bap gene, which codes for the biofilm-associated protein was identified in biofilm producing Staphylococcus, by PCR. Amongst CPS, 10 (38.46%) and 6 (23.07%) isolates were positive for biofilm formation, while 15 (71.4%) and 9 (42.85%) isolates amongst CNS were positive for biofilm formation by CRA and tube method, respectively. Biofilm formation genes bap (size 971 bp) was detected only in S. aureus.