Considerations for the use of essential oils, tannins, curcumin and organic acids in poultry production as alternatives to antimicrobials

SUMMARYA growing trend towards sustainable, antibiotic-free production is being propelled by stricter regulations and an increasing consumer desire for poultry products that are free from antibiotics. This has sparked a more intense search for effective natural alternatives. Phytogenic feed additives (PFAs), which are also called phytobiotics or phytochemicals, have emerged as promising candidates because of their growth-promoting, antimicrobial and immunomodulatory benefits. Commonly administered via feed, water or in ovo, PFAs include essential oils, tannins and curcumin. Essential oils, part of the terpenoid family, show complex chemical profiles that provide both antimicrobial and anti-inflammatory effects. Tannins, which are polyphenolic compounds, come in various forms (condensed, hydrolysable and phlorotannins), and they play an important role in supporting gut health and pathogen control. Curcumin, extracted from the rhizomes of Curcuma plant, has antioxidant and anti-inflammatory benefits. Besides PFAs, organic acids and their salts have been included in poultry nutrition for years. They support performance by modulating gut pH and inhibiting pathogenic bacteria. So, this review examines the mechanism of action, efficacy, limitations and optimisation strategies for these compounds, highlighting their potential as viable alternatives to infeed antibiotics for enhancing poultry health and productivity while aligning with consumer expectations for sustainable production.