Phytogenic and prebiotic feed additives as antibiotic substitutes: effects on broiler meat quality, organ properties, and production efficiency when fed standard and reduced energy and protein diets

This study investigated the impact of reduced dietary metabolizable energy (ME) and crude protein (CP) levels on broiler breast meat quality, internal organ yields, feed efficiency (FE), and the European production efficiency factor (EPEF), with or without phytogenic feed additive (PFA) or prebiotic supplementation. Two base diets were used: a reduced-energy and protein diet (−1.5% ME, −5% amino acid density) as the negative control (NC1) and a standard corn–soybean diet as the positive control (PC1). Each was supplemented with PFA (0.15% or 0.25%) or 0.10% prebiotic, resulting in eight treatments. A total of 576 Ross 308 chicks were allocated to these treatments and reared for 35 days. The results showed that reduced ME and CP diets impaired meat quality and performance, with NC1 showing the poorest results. Supplementation with 0.25% PFA in the PC1 diet improved water holding capacity (+6.32%), reduced drip loss (−25.38%) and cooking loss (−27.29%), enhanced tenderness of breast meat, and improved FE (+4.7%) and EPEF (+12.9%). Organ weights improved under NC1 with 0.25% PFA, and prebiotics improved meat color. In conclusion, while ME and CP reduction impaired broiler performance and meat quality, PFA-especially at 0.25% in a standard diet-effectively mitigated these effects. Phytogenic feed additives are an effective supplement for generating high-quality broiler meat, especially at higher inclusion levels, even in low energy and protein diets.Plant-based feed additives showed the potential to enhance feed efficiency and production efficiency, particularly at higher inclusion levels, even under reduced energy and protein diets.The PC1 + 0.25% PFA group showed a 4.7% increase in feed efficiency and a 12.9% increase in European production efficiency over NC1.The immune organs (Bursa) and digestive organs (gizzard and proventriculus) were larger in groups treated with Phytogenic feed additives and particularly NC1 + 0.25% PFA.Phytogenic feed additives are an interesting tool for producing high-grade broiler meat, contributing significantly to several key meat quality characteristics. Phytogenic feed additives are an effective supplement for generating high-quality broiler meat, especially at higher inclusion levels, even in low energy and protein diets. Plant-based feed additives showed the potential to enhance feed efficiency and production efficiency, particularly at higher inclusion levels, even under reduced energy and protein diets. The PC1 + 0.25% PFA group showed a 4.7% increase in feed efficiency and a 12.9% increase in European production efficiency over NC1. The immune organs (Bursa) and digestive organs (gizzard and proventriculus) were larger in groups treated with Phytogenic feed additives and particularly NC1 + 0.25% PFA. Phytogenic feed additives are an interesting tool for producing high-grade broiler meat, contributing significantly to several key meat quality characteristics.