Colisepticaemia of lambs

In 1979 and 1980, 23 and 29 cases of ovine colisepticaemia from 16 and 18 properties respectively were diagnosed. All cases but one were caused by Escherichia coli 078: NM (Non Motile). Mortality ranged from 1% to 5% with an age distribution of 3 to 12 weeks. Most cases occurred in October. Thirty-three of the isolates were tested against a wide range of antibiotics and all had similar sensitivity patterns. E. coli 078 was detected less frequently in rectal cultures than in bile, small intestinal or nasal cultures from colisepticaemic lambs. In addition, E. coli 078 was recovered more frequently from nasal than from rectal cultures of lambs dying from causes other than colisepticaemia in colisepticaemic flocks. These findings suggest that perhaps the nasal route may be the more important portal of infection in ovine colisepticaemia caused by E. Coli 078 organisms.