Extended-Spectrum β-Lactamase CTX-M-1 in <i>Escherichia coli</i> Isolates from Healthy Poultry in France

Genes encoding extended-spectrum beta-lactamase CTX-M-1 were detected in 12 Escherichia coli isolates recovered over a 7-month period from the ceca of healthy poultry in seven districts in France in 2005. Eleven of those strains were not clonally related and had a bla(CTX-M-1) gene located on transferable plasmids of different sizes and structures.