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Chicken <i>Salmonella enterica</i> serovars are enteric bacteria associated with massive public health risks and economic losses. There is a widespread antimicrobial resistance among <i>S.</i> <i>enterica</i> serotypes, and innovative solutions to antibiotic resistance are needed. We aimed to use probiotics to reduce antibiotic resistance and identify the major probiotic players that modify the early interactions between <i>S.</i> <i>enterica</i> and host cells. One-day-old cobb broiler chicks were challenged with <i>S. typhimurium</i> after oral inoculation with different probiotic strains for 3 days. The adherence of different probiotic strains to Caco-2 intestinal epithelial cells was studied in vitro. <i>Lactobacillus</i> (<i>Lacticaseibacillus</i>) <i>casei</i> ATTC334 and <i>Bifidobacterium breve</i> JCM1192 strains attached to Caco-2 cells stronger than <i>B. infantis</i> BL2416. <i>L. casei</i> ATTC334 and <i>B. breve</i> JCM1192 reduced <i>S. typhimurium</i> recovery from the cecal tonsils by competitive exclusion mechanism. Although <i>B. infantis</i> BL2416 bound poorly to Caco-2 epithelial cells, it reduced <i>S. typhimurium</i> recovery and increased IFN-γ and TNF-α production. <i>L. casei</i> ATTC334, <i>B. breve</i> JCM1192 and <i>B. infantis</i> BL2416 improved body weight gain and the food conversion rate in <i>S. typhimurium</i>-infected broilers. <i>B. longum</i> Ncc2785 neither attached to epithelial cells nor induced IFN-γ and TNF-α release and consequently did not prevent <i>S. typhimurium</i> colonization in broiler chickens. In conclusion, probiotics prevented the intestinal colonization of <i>S. typhimurium</i> in infected chickens by competitive exclusion or cytokine production mechanisms.