Mitigating Salmonella in Poultry Using Probiotics: Mechanisms, Challenges, and Opportunities

The global poultry industry continues to face significant challenges due to <i>Salmonella</i> infections, which pose severe public health concerns and economic losses. Recently, the reemergence of antimicrobial resistance has led to the restriction of antibiotic use in poultry, especially as growth promoters, thus accelerating the search for sustainable alternatives. Among these, probiotics have gained attention as potential candidates for improving poultry health and mitigating <i>Salmonella</i> colonization in the gut. This review summarizes the key mechanisms through which probiotics exert anti-<i>Salmonella</i> effects, including competitive exclusion, production of antimicrobial substances, reinforcement of the intestinal barrier, and modulation of host immune responses. Commonly used probiotic strains in poultry such as <i>Lactobacillus</i> and <i>Bacillus</i> are discussed, alongside emerging candidates derived from non-poultry hosts that may offer additional functional benefits. Despite encouraging findings, the use of probiotics in poultry faces several challenges, including strain-specific efficacy, variation in results across studies, environmental influences, and regulatory limitations. Therefore, we further explore future directions that are aimed at improving probiotic application in poultry production, such as microbiome-guided strain selection, advanced delivery systems, and combination therapies. Advancing our understanding of probiotic-pathogen-host interactions will be essential for optimizing probiotic use to enhance poultry health, reduce zoonotic transmission of <i>Salmonella</i>, and contribute to safer and more sustainable food systems.