INTRAMAMMARY IMMUNIZATION WITH LIVE-ATTENUATED STAPHYLOCOCCUS-AUREUS PROTECTS MICE FROM EXPERIMENTAL MASTITIS

Female mice were immunized by the intramammary route with live-attenua ted Staphylococcus aureus according to different schedules and challen ged with virulent S. aureus. Immunization in late pregnancy or early l actation induced a significant decrease (P < 0.05) in the number of S. aureus CFU recovered from glands after the challenge and a significan t increase (P < 0.05) in the levels of milk and serum specific IgG and ISA antibodies. Mice immunized before pregnancy were not protected fr om S. aureus challenge. Immunization did not increase the number of so matic cells in milk when compared with control mice. Protection from S . aureus intramammary infection may be achieved if mice are locally im munized during late pregnancy or early lactation. (C) 1998 Federation of European Microbiological Societies. Published by Elsevier Science B .V.