NOTE - INHIBITION OF THE GROWTH OF YERSINIA-ENTEROCOLITICA O-3 BY THEMICROFLORA OF PORCINE CECUM AND ILEUM IN AN IN-VITRO MODEL

The growth of Yersinia enterocolitica O:3 was tested in an in vitro mo del of the porcine intestine at the physiological temperature of 39 de grees C of growing pigs. The model supported a stable population of Y. enterocolitica at a level 10(8)-10(9) cells ml(-1). Plasmid profile a nalysis and the Ca2+-dependent proportion of the population suggested that the great majority of the Y. enterocolitica population retained t he 70 kb virulence plasmid, pYV, throughout the experimental period of 5 d, The growth of Y. enterocolitica was substantially inhibited by t he ileal and the caecal flora compared to the growth of the bacterium alone. Yersinia enterocolitica was not isolated after 3 d of cultivati on.