The authors examined the prevalence of staphylococci (aureus and non-Staphylococcus aureus) causing intramammary infections (IMI) during dairy cows' nonlactating periods. They concluded that "[f]irst lactation cows had a higher prevalence of staphylococcal IMI at calving than multiparous cows. In first lactation cows, the most prevalent staphylococcal IMI in early lactation was S. chromogenes IMI, which led to a substantial elevation of SCS [somatic cell score] during the following lactation. However, quarter-level milk production was not affected by S. chromogenes IMI in primiparous cows. Some staphylococcal species were more frequent in older cows."