IN-VITRO SUSCEPTIBILITY OF BOVINE MASTITIS PATHOGENS

87 Streptococci-, 161 S. aureus- and 100 Enterobacteriaceae strains we re isolated from bovine mastitis cases. They were tested regarding in- vitro sensitivity against 11 different antibiotics. Minimal inhibitory concentrations were determined by means of Sensititre(R)-microplate m ethod, by which evidence is given concerning essential tissue concentr ations. Streptococci displayed very different resistance pattern again st antibiotics, Enterococci an evident higher resistance against penic illin. More than 80 % of S. aureus strains tested were highly sensitiv e to beta-lactamantibiotics and aminoglycosides as well. Our examinati ons have shown that aminoglycosides as well as cephalosporines are rec ommended for therapeutic use in case of mastitis caused by gram-negati ve pathogens.