Preventive antimicrobial action and tissue architecture ameliorations of Bacillus subtilis in challenged broilers

Probiotics improve intestinal balance through bacterial antagonism and competitive exclusion. This study aimed to investigate the o antimicrobial activity, as well as the o preventive, immunological, productive, and histopathological modifications produced by probiotic s. The antimicrobial activities of (5×10 CFU/g; 0.5, 1.0*, 1.5, and 2.0 g/L) were tested against O157: H7, Typhimurium, , and after exposure times of 0.25, 0.5, 1, and 2 h using minimal inhibitory concentration procedures. A total of 320 1-day-old female Ross broiler chickens were divided into five groups. Four out of the five groups were supplemented with 0.5, 1.0*, 1.5, and 2.0 g/L probiotic from the age of 1 day old. Supplemented 14-day-old broiler chickens were challenged with only O157: H7 (4.5×10 CFU/mL) and . Typhimurium (1.2×10 CFU/mL). A total of 2461 samples (256 microbial-probiotic mixtures, 315 sera, 315 duodenal swabs, and 1575 organs) were collected. The results revealed highly significant (p