Detection of hla and hlb gene in Staphylococcus aureus isolates from buffaloes with subclinical mastitis

Abstract

Staphylococcus aureus (S. aureus) is a spherical, non-motile, gram-positive non-spore forming bacterium which plays a critical role to cause subclinical mastitis in buffaloes. In present study 84 milk samples were collected from Hanumangarh city, 41 S. aureus isolate were isolated with a recovery of 48.80%. All 41 samples were genotypically confirmed by 23S rRNA based ribotyping method. All the 41 isolates were typable for haemolysin genes where hla gene was detected in 37 (90.24%) and hlb gene in 34 (82.92%) isolates. On sheep blood agar 25 isolates (60.97%) produced complete hemolysis, four (9.75%) incomplete hemolysis both complete and incomplete by four (9.75%) while eight (19.51%) isolates did not produce any hemolysis. Hence S. aureus isolates obtained from buffaloes with subclinical mastitis showed higher percentage of haemolysin both genotypically and phenotypically.