Tetramethylpyrazine supplementation reduced Salmonella Typhimurium load and inflammatory response in broilers

The present study tested whether tetramethylpyrazine (TMP) supplementation could influence the growth performance, Salmonella Typhimurium (S. Typhimurium) load, inflammasomes, cytokines, and chemokines in broilers. Treatments were a 2 × 2 factorial design, including negative control (NC), S. Typhimurium challenge (SC), and NC/SC + TMP (150 mg/kg of diet). The trial lasted for 28 D, and S. Typhimurium subclinical challenge was occurred on day 8. The results showed that S. Typhimurium challenge worsened (P < 0.05) growth performance, S. Typhimurium load in intestinal digesta and visceral tissues, intestinal inflammatory responses, and permeability compared to the NC treatment. TMP supplementation increased (P < 0.05) feed intake, weight gain, and feed efficiency by 4.3 to 12.0%, but decreased (P < 0.05) S. Typhimurium load by 5.4 to 45.8%, inflammasomes (caspase-1/3/9, gasdermin A/E, and nod-like receptor protein 3) by 25.0 to 59.0%, chemokines (C-C motif ligand 2 and C-X-C motif 10) by 40.2 to 47.2%, intestinal permeability by 28.2% compared to the SC treatment. The TMP also reduced inflammatory response by influencing tumor necrosis factor α, interleukin 1β/4/6. Factorial analysis indicated that TMP and SC were interactive (P < 0.05) on most parameters due to the more pronounced TMP effect in S. Typhimurium challenge groups. It is concluded that TMP can promote growth and mitigate S. Typhimurium infection by reducing the S. Typhimurium load and inflammatory response in broilers.