Investigation of coagulase (COA) and protein A (SPA) virulence genes in staphylococci isolated from mastitis milk

Objective: In this study, it was aimed to determine coagulase (coa) and protein A (spa) virulence genes from staphylococci isolated from milk with mastitis. Materials and Methods: Materials and Methods: 100 milk samples collected from private dairy farms were delivered to Adnan Menderes University Veterinary Faculty Microbiology Department laboratory in cold chain, sown in media and left for incubation. The coagulase (coa) and protein A (spa) virulence genes of the isolates identified as staphylococci in the study will be determined by PCR method (Çiftci et al. 2009). Results: 100 milk samples used in the research were incubated at 37°C for 18 hours as a result of sowing on the media. Bacterial growth was observed in all isolates. Gram-positive cocci were detected. 33 of them were detected as Gram positive cocci. As a result of the catalase test, 25 of them were positive. Coagulase test was performed on 25 catalase positive samples and 11 samples were evaluated as positive. PCR was performed to evaluate the catalase positive samples for Staphylococcus spp. and Staphylococcus aureus. As a result of PCR, 25 isolates of catalase positive were detected as Staphylococcus spp. and 7 isolates as Staphylococcus aureus. When the presence of spa and coa genes was examined, the presence of coa gene was detected in 7 isolates from 25 isolates with Staphylococcus spp., while the presence of spa gene was detected in 11 isolates. Conclusion: Staphylococcus spp. and S. aureus were identified from 100 milk samples and 25 isolates were identified as Staphylococcus spp., 11 isolates as Staphylococcus aureus. The presence of protein A (spa) and coagulase (coa) genes in isolates detected as Staphylococcus spp. was analyzed by PCR method. While 11 of 25 isolates were positive for the presence of spa gene, 7 isolates with coa gene were detected.