Fuente: PubMed "essential oil" Poult Sci. 2026 Jun 10;105(11):107272. doi: 10.1016/j.psj.2026.107272. Online ahead of print.ABSTRACTSalmonella enterica is a major food safety concern in broiler production due to its persistence in the gastrointestinal tract, internal organs, and production environment. This study evaluated the effects of dietary thymol-rich and carvacrol-rich essential oil feed additives on colonization and persistence patterns of Salmonella Typhimurium (ST) in broiler chickens. A day-old Ross 708 male broiler chicks (n = 1200) were randomly allocated to 6 dietary treatments: PC, positive control standard diet without any essential oil additive; CARVA1, a feed additive (Salvix) containing 50% carvacrol included at 1,100 g per ton of feed; CARVA2, Salvix included at 2,200 g per ton; THYM1, a feed additive (Esencial Premix) containing 45% thymol included at 250 g per ton; THYM2, Esencial Premix included at 500 g per ton; and COMBO, a combination of CARVA1 and THYM1, with 8 replicates (25 birds each) per treatment. All birds were orally challenged with 7 Log CFU/ml of ST on placement day. Samples were collected from liver, spleen, ceca, litter boot swabs, and carcass rinses to determine Salmonella counts and prevalence. No significant differences (P > 0.05) in Salmonella counts (CFU/mL) in cecal and carcass rinse samples were observed among treatments. CARVA1 decreased (P = 0.003) Salmonella counts in boot swabs compared with PC, CARVA2, THYM1, and COMBO on day 14. COMBO decreased (P < 0.05) Salmonella prevalence in the liver, whereas CARVA1 decreased (P < 0.05) in the spleen, compared to all other diets on day 14. No differences (P > 0.05) were observed in Salmonella prevalence in cecal, boot swab, and carcass rinse samples post-enrichment. Pearson correlation analysis revealed generally weak and non-significant associations between cecal Salmonella counts and environmental or carcass contamination, with a single significant positive correlation observed between cecal and boot swab counts on day 14 in the CARVA2 group. In summary, supplementation with thymol-rich and carvacrol-rich essential oils produced limited and matrix-dependent effects on Salmonella recovery, with transient reductions observed in boot swab counts and internal organ prevalence at day 14 but no consistent effects on cecal counts, cecal prevalence, or carcass contamination.PMID:42531847 | DOI:10.1016/j.psj.2026.107272