Quantified standard to be used as a positive control or PCR quantification standard Vigorously quantified using multiple methods Mastitis is the single most costly disease of dairy cattle resulting in the reduction of milk yield and quality. The inflammation of the utter is mainly caused by bacteria, and Staphylococcus aureus (S. aureus) is often considered the most common cause of contagious mastitis in dairy herds. S. aureus infection is estimated to be present in up to 90% of dairy farms and is responsible for 35% of the economic loss in the dairy industry. S. aureus is a facultatively anaerobic, Gram positive bacterium. The majority of S. aureus strains are catalase-positive and coagulase-positive, which forms the basis of traditional identification methodology. Staphylococcus aureus Quantified Bacterial DNA Standard is prepared from cultured bacteria using Norgen’s sample preparation technology. The purified DNA is quantified vigorously using multiple methods including spectrophotometry, gel densitometry and real-time PCR. It is intended to be used as a positive control or PCR quantification standard for Staphylococcus aureus.