Optimizing male layer chicken performance and health with probiotic supplementation: A sustainable alternative to antibiotic growth promoters.

Background: The rising global concern over antibiotic resistance has heightened scrutiny of antibiotic growth promoters (AGPs) in poultry farming, prompting a shift toward alternative feed additives to ensure sustainable and safe poultry production. This trend aligns with the increasing demand for free-range and naturally raised chicken meat in various regions, including Indonesia. In response, Indonesian breeders have turned to medium-sized male layer chickens (MLCs) as substitutes for traditional free-range chickens. This practice, coupled with the need to replace AGPs, highlights the critical importance of exploring innovative and natural solutions to enhance poultry growth and health. Aim: This study investigated the effects of probiotics as an alternative to AGPs on the growth performance, carcass traits, and immune organs of male ISA Brown layer chickens. Methods: The 180-day-old male ISA Brown layer chickens were used for the study. The intervention included six treatments. T1 basal feed, T2 2.5 g AGP/kg feed, T3 1 ml probiotic/kg feed, T4 3 ml probiotic/kg feed, T5 4 ml probiotic/kg feed, and T6 5 ml probiotic/kg feed. Probiotics used were Results: The findings demonstrate that probiotic supplementation significantly outperformed the AGP-treated group (T2) in enhancing growth performance, carcass weight, pectoral weight development, FCR, internal and immune organ weights, nutrient intake, and digestibility. While AGPs showed improvements over the control (T1), probiotic- supplemented groups, particularly T6, achieved superior results across all parameters, indicating that probiotics are not only a viable alternative to AGPs but also a more effective and sustainable approach for poultry production. Conclusion: The probiotics used in the study at 4 and 5 ml/kg of feed significantly enhanced the performance, immune organ development, and carcass attributes of MLCs, demonstrating their effectiveness as a viable alternative to AGPs. These findings highlight the potential of probiotics to improve poultry production sustainability by reducing reliance on antibiotics, enhancing growth and health outcomes, and promoting animal welfare through natural and efficient dietary interventions.