Abstract
The present study was designed to find the effect of an antibiotic, an organic acid and a probiotic on performance traits, blood biochemical parameters and antioxidant status during the starter phase exposed to Salmonella typhimurium challenge. A total of 300 day-old broiler chicks were randomly allocated to control (basal diet), T1: infected with Salmonella enteric subsp. Typhimurium; T2: infected + avilamycin; T3: infected + organic acid; T4: infected + Bacillus subtilis; T5: infected + organic acid + probiotic. The results showed that body weight, feed conversion ratio and production efficiency factor did not differ (P > .05) between the control and treated groups. Blood albumin and aspartate aminotransferase increased significantly (P < .05) in birds in T5 during the first week. Similarly, total protein and triglyceride concentration increased significantly (P < .05) in T4 and T5. The total antioxidant capacity in the second week decreased significantly in T4 compared to the control. Thiobarbituric acid reactive substances during the first and second weeks did not differ significantly (P > .05) between the control and treated groups. We concluded that the effect of organic acid blend and B. subtilis was similar to that of the antibiotic in broilers during the starter phase exposed to S. typhimurium challenge.