Avian Pathogenic E. coli (APEC) colibacillosis is a highly fatal, multisystemic bacterial infection of broilers with high mortality rates, reduced productivity, and inferior growth rates. The current study aimed to evaluate the effectiveness of pomegranate-coated zinc oxide nanoparticles (PEE-ZnONPs) at different concentrations against E. coli infection (Colibacillosis) in broiler chicks, considering the increasing E. coli antibiotic resistance. One hundred and fifty chicks were divided into five groups: G1: a negative control; G2: a positive control with E. coli O78 infection; and three treatment groups with 40 mg/L as G3, 80 mg/L as G4, and 120 mg/L as G5 of PEE-ZnONPs in their drinking water for 35 days. Bird performance and deaths were monitored throughout the duration of the study, and intestinal tissue samples were prepared for molecular and pathologic analysis. The findings showed that the supplementation of PEE-ZnONPs significantly improved the body weight, feed consumption, and feed conversion ratio relative to the infected control (P |