ETIOLOGY OF DIARRHEA IN PIGS WEANED AT 2 DAYS OF AGE

When pigs are weaned at 2 days of age large numbers of Escherichia coli appear in the anterior gut and incidence of diarrhea rises. The 2 phenomena do not appear directly related because strains of E. coli isolated are not serotypes previously associated with neonatal pig scouring. Representative strains of the non-enteropathogenic serotypes did not produce enterotoxin and did not adhere to small intestine brush borders. When antibiotics were fed to eliminate E. coli from the gut, the pigs still scoured. Rotavirus was detected in the gut contents and gut epithelium of scouring pigs and a bacteria-free filtrate of gut contents produced diarrhea when administered to germ-free pigs. Rotavirus may be 1 cause of the scouring seen shortly after weaning pigs at 2 days of age.