Effect of feeding processed Soybean Meal on broiler’s performance, intestinal morphology, cecal microbial population and immune response

This study aimed to assess the effects of different levels of processed soybean meal (PSBM) on the growth performance, intestinal morphology, cecal bacterial count, and immune responses of broilers. A total of 560 Ross 308 broiler chickens were randomly assigned to seven groups. The control group received a basal diet based on standard soybean meal (SBM). Groups S1 (starter 1), G1 (grower 1), and F1 (full period 1) received diets containing 2.5% PSBM, while Groups S2, G2, and F2 received diets containing 5% PSBM at each life phase, respectively. The results demonstrated that average daily weight gain and feed conversion ratio were significantly improved in the groups fed the 5% PSBM diet. Additionally, PSBM replacement did not affect villus length in any intestinal region. Nevertheless, increasing dietary PSBM content reduced intestinal goblet cell number (P<0.01) and cecal Clostridia population (P<0.01). Furthermore, PSBM enhanced bronchitis antibody titers and immune responses against PHA at 24 and 48 hours after injection, respectively (P<0.01). In conclusion, adding 5% PSBM to regular SBM is recommended, particularly in the grower phase, due to its positive effects on broilers.