Increased survival in calves of Escherichia coli K-12 carrying an Ent plasmid

Escherichia coli K-12 strains with and without an Ent plasmid were fed to calves, and the survival of each was monitored by viable bacterial counts of the feces. The E. coli K-12 strain carrying the Ent plasmid survived in the calves at significantly higher levels and for a longer period of time than the E. coli F(-) stain.