author(s)
Suhaib Ul Haq Khan, Shafqut Majeed Khan, Aadil Majeed, Aiman Ashraf, Aasim Habib, Jaan Mohammad Wani, Rajesh Kumar and Raj Narayan Trivedi

abstract
Mastitis is one of the main diseases affecting the dairy cattle around the world. It causes huge economical losses to dairy farmers worldwide. Staphylococcus aureus is one of the pathogens implicated in bovine mastitis. The S. aureus is a coagulase positive, facultative anaerobic bacterium and can be microscopically characterized as single, pairs or cluster of Gram-positive cocci. In current study 50 milk samples from a dairy farm were screened for Staphylococcus aureus. positive samples were checked for antibiotic sensitivity with ampicillin (5mcg). Isolates resistant to ampicillin were selected for treatment with silver nanoparticles. Silver nanoparticles were used at a concentration of 8 µg/ml and zone of inhibition was measured using ABST scale. Silver nanoparticles showed a zone of inhibition comparable to zone shown by Staphylococcus aureus sensitive to ampicillin.