Impact of virulence genes and pathotypes of intestinal pathogenic Escherichia coli on gastrointestinal lesions in pre- and post-weaning piglets

Strong associations between specific VGs - particularly <i>faeG</i>, <i>eltA</i>, <i>estII</i>, <i>paa</i>, and <i>astA</i> - and higher lesion scores show that VG detection can help predict disease severity and guide interventions. Age-specific interpretation is crucial, as isolates from pre-weaned piglets often carried more VGs and were associated with more severe lesions. This study underscores the value of integrating bacteriological, molecular and histopathological data for accurate diagnosis, especially given the high prevalence of VG-positive and recombinant ETEC strains.