From a group of 11 recently weaned pigs, 4 were reported to be sick. Clinic
al examination of the sick pigs revealed marked dyspnoea, bluish-red discol
ouration of the skin, incoordination and difficulty in walking. Bacteriolog
ical examination of the gut contents of 2 pigs that had died earlier yielde
d pure cultures of haemolytic Escherichia coli. Post mortem examination of
the remaining 2 pigs that died subsequently revealed progressive pulmonary
collapse. One of these also showed subcutaneous oedema of the head and mark
ed oedema of the mesentery of the spiral colon and oedema of the brain. Mic
roscopically there was pulmonary alveolar collapse and degenerative changes
in the liver. On the basis of the clinical signs, isolation of haemolytic
E. coli and the post mortem findings, a diagnosis of oedema disease was mad
e.