Occurrence of β-lactam-resistant Staphylococcus aureus in milk from primiparous dairy cows in the northeastern region of Brazil.

The objective of the current study was to isolate and identify Staphylococcus (S.) aureus strains resistant to beta-lactam antibiotics from primiparous cows' milk. A total of 432 milk samples were collected from all primiparous dairy cows in early lactation that originated from 9 dairy properties.