Antibiotic resistance in Staphylococcus aureus isolated from milk of mastitis affected goats

Staphylococcus aureus is one of the most important bacterial pathogens for infectious mastitis in dairy animals including goats. Mutation and acquiring of exogenous genes by S. aureus have resulted in emergence of antibiotic resistance strains. During March to July 2019, a total of 29 S. aureus isolates were isolated from milk of mastitis affected goats of farmers flocks of Jhunjhunu district (Rajasthan). The isolates were genotypically confirmed by 23S rRNA ribotyping for S. aureus. A total of 14 antibiotics belonging to different classes were used to carry out antibiogram study against all the 29 isolates. Of the 14 antibiotics, imipenem was detected effective against all the isolates, followed by gentamicin (93.00%), cefotaxime + clavulanic acid (82.75%), cefazolin and cefepime (79.31%), whereas ampicillin resistance was observed in all the 29 isolates (100%). Highest resistance was shown towards ampicillin by all the isolates suggests a possibility of potential public health threat through consumption of milk and milk products.