The study presents a massive culture-based approach for the screening of AmpC, ESBL, and carbapenemase producers from rectal swabs, demonstrating improved specificity for detecting ESBL producers compared to conventional methods. It identifies various beta-lactamase genes, including bla CTX-M-1/2-like, bla CTX-M-8-like, bla CTX-M-9-like, bla SHV-like, bla TEM-like, bla GES-like, bla MOX, bla CIT, bla DHA, bla ACC, bla EBC, bla FOX, bla CMY-2, and bla NDM.