Effects of fermented soybean meal on digestive enzyme activities and intestinal morphology in broilers

The experiment was performed to compare the effects of fermented soybean meal (fermented with Aspergillus oryzae 3.042, FSBM) and soybean meal on digestive enzyme activities and intestinal morphology in broilers. Three hundred twenty 1-d-old Ross x Ross male broiler chicks were randomly allocated into 2 dietary treatments for a 6-wk feeding trial, including 0- to 21-d and 21- to 42-d periods. At the end of each stage, 8 broilers of each treatment were killed, and pancreas, small intestine digesta, and duodenum, jejunum, and ileum segments were collected for digestive enzymes and intestinal morphology evaluation. Results of the experiment showed that replacing soybean meal with FSBM in diet increased the activities of trypsin, lipase, and protease significantly in intestinal content of starter broilers (P<0.05) and enhanced the protease activity of grower broilers (P<0.05). Amylase activity was not affected in both feeding periods by the treatments. Compared with the control, broilers fed with FSBM had lower pancreatic trypsin activity (P<0.05) in the starter phase. There were no significant differences on lipase, amylase, and protease activity between the treatments in both growth phases. Increased villus height (P<0.05) and decreased crypt depth (P<0.05) of jejunum mucosa could be observed in the whole growth stage of broilers fed with FSBM. Also, duodenal villus height of starter chicks was also significantly increased (P<0.05).