LOCATION OF STAPHYLOCOCCUS-AUREUS IN EXPERIMENTAL CHRONIC MASTITIS IN THE MOUSE AND THE EFFECT ON THE ACTION OF SODIUM CLOXACILLIN

Abstract

Chronic staphylococcal mastitis was established in the mouse and EM examination of mammary tissue showed that staphylococci were within epithelial cells, neutrophils and macrophages. Suspensions of cells containing staphylococci were prepared from chronically infected glands and incubated with sodium cloxacillin in vitro. This procedure resulted in a reduction in bacterial numbers but significantly greater reduction was obtained if somatic cells were disrupted by sonication before addition of cloxacillin. The intracellular location of the staphylococci may protect them against the action of the antibiotic.