An experiment with 630 one-day-old chicks experimentally inoculated with Salmonella Typhimurium was performed to evaluate the effects of an organic acid blend (benzoic, fumaric and 2-hydroxi-4-methylltio-butanoic - HMTBa) on intestinal health and performance. The experimental challenge with Salmonella Typhimurium occurred in two different routes of administration: via crop on the first day after hatching, and via feed, offered from seven to 14 days of age. These groups were treated with organic acids in a 3 × 2 (agent versus acid) factorial arrangement. Chicks treated with organic acids had higher weight gain, mean live weight and better feed conversion at 14 days of age, and higher weight gain at 28 days of age. Chicks treated with organic acids inoculated via crop had higher duodenum villi height than animals of the control group. Jejunum villi were higher in chicks of the negative control group compared with birds supplemented with organic acids. Small intestine pH in chicks of the inoculated group was lower compared with control group throughout the trial period. HMTBa acid in the dosage of 0.4% improves intestinal health and performance when nalidixic acid resistant Salmonella Typhimurium is experimentally inoculated.