Probiotics in Poultry: A Comprehensive Review of Mechanisms, Applications, and Future Directions

Abstract

Simple Summary Many countries have banned antibiotic growth promoters in poultry feed, creating an urgent demand for safe and sustainable alternatives. Probiotics are one of the most promising substitutes to maintain poultry gut health and production performance. This review summarizes how probiotics protect chickens by suppressing harmful bacteria, repairing intestinal barriers and regulating immunity, and outlines their ability to relieve heat stress, mycotoxin damage and other common farming challenges. We also discuss the practical value of probiotics for preventing necrotic enteritis, salmonellosis and other bacterial diseases, as well as advanced forms including multistrain mixtures, synbiotics and postbiotics. At present, inconsistent on-farm results limit large-scale probiotic application, which is mainly caused by blind strain matching, lack of unified usage standards and oversimplified laboratory research models. We put forward targeted research ideas based on multi-omics screening, unified evaluation systems and field trials under complex stress conditions. This paper provides clear theoretical guidance for developing and using probiotic products in antibiotic-free poultry production.