Dual Role of Caprylic Acid as Antimicrobial Agent, Neomycin Residue Reduction and Antioxidant Defense in Broiler Chickens infected experimentally with Avian Pathogenic Escherichia Coli

Colibacillosis in chickens, is an economically significant bacterial disease all over the world, caused by pathogenic Escherichi coli.The study investigated the influence of dietary caprylic acid on neomycin residue depletion, oxidative stress and hepatorenal function in Escherichia coli challenged broilers. 180 male Cobb 500 chicks were randomly allocated to six dietary groups and reared under hygienic conditions. Birds were orally challenged with Avian Pathogenic Escherichia Coli (APEC), and treatments included neomycin (30 mg/kg body weight) and/or caprylic acid (1%), administered either prophylactically or post-infection. E. coli challenge markedly elevated cecal bacterial counts (7.14 × 106 CFU/g) and mortality rate (30%) in APEC infected without treatment, while both neomycin and caprylic acid significantly reduced these outcomes. The combined therapy yielded the greatest reduction count (2.5 × 106 CFU/g with 3% mortality rate). Neomycin residues declined progressively, with significantly faster clearance in caprylic acid–treated groups, shortening the withdrawal time. Calculated withdrawal period from three to four days. Caprylic acid also attenuated E. coli-induced oxidative stress, restoring antioxidant enzyme activities and improving serum hepatic and renal biomarkers. Early administration produced the most pronounced effects, while combination therapy demonstrated synergistic benefits. These findings highlight caprylic acid has dual functionality in enhancing drug clearance and antioxidant defense, supporting its potential as a food-safe intervention to improve broiler health and reduce risks associated with antimicrobial residues.