Synergistic roles of citric and formic acids and their salts on broiler health and performance

1. Organic acids have shown promise as safe and natural growth enhancers when added to broiler diets. 2. The current study aimed to assess how adding organic acids and their salts (OA+S) affected the intestinal microbiota, growth performance, antioxidant status and blood biochemical markers in broiler chickens.Four groups, each consisting of 90 chicks divided into six replicates (15 chicks per replicate), were randomly selected from 360 one-day-old chicks with similar initial body weights. 3. Birds fed a basal diet and received either: T1 (no addition; CTRL), T2 (1.5 g/kg feed formic acid + sodium formate, FFA), T3 (1.5 g/kg citric acid + sodium citrate, CCA) or T4 (0.75 g/kg each of FFA and CCA, MIX).Broilers fed MIX had the best BWG and FCR (<i>p</i> ≤ 0.05).4. All treatments significantly (<i>p</i> ≤ 0.05) improved performance compared to the control group. Antioxidant enzyme concentrations were higher in broiler chicks administered a combination of OA and their salts (FFA and CCA) relative to CTRL. 5. The levels of creatinine, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were not affected (<i>p</i> > 0.05) among all groups.6. The addition of FFA significantly elevated thyroid hormone levels (<i>p</i> ≤ 0.05); however, they remained within the normal range. 7. Feeding MIX enhanced immune responses to avian influenza H5, H9 and Newcastle disease ND titre compared to birds fed CTRL. 8. <i>Lactobacillus</i> spp. and total bacterial counts were higher in the FFA supplemented group than in CTRL.9. Broilers fed FFA had enhanced growth, better antioxidant status, improved gut microbiome and improved serum biochemical indicators, making it a safe and effective alternative to conventional antimicrobial growth promoters.