Figure 1

Median (a) and mean values with standard error (b) of the diversity of the enteric coliform flora in the ileo-caecal ostium (open squares) and rectum (filled squares) of 7 conventional Yorkshire castrates following insertion of an ileo-ceacal cannula on day 0. To minimise the risk for postoperative infections a single intramuscular injection with a long acting derivate of oxytetracycline was given in connection to surgery. At surgery the pigs were aged 12 weeks.