Effect of two different casein hydrolysates on small intestinal bacteria of growing pigs

Abstract:

[Objective] This study was aimed to explore the effect of different casein hydrolysates on small intestinal bacteria of pigs.[Methods] Luminal and gut wall bacteria from duodenum, jejunum and ileum in Duroc, Landrace and Yorkshire hybridization pigs were used as inocula. Casein acid hydrolysate and casein enzymatic hydrolysate were fermented at 37℃ for 12 h. Samples were collected at 0, 3, 6 and 12 h to measure microbial protein and detect the alteration of bacteria community.[Results] After inoculated with the luminal bacteria, the concentration of microbial protein in duodenum and ileum in casein enzymatic hydrolysate group was higher compared with casein acid hydrolysate group and the casein enzymatic hydrolysate group had higher total bacteria number and Firmicutes in duodenum after 12 h incubation (P<0.05). In the casein enzymatic hydrolysate group, the numbers of total bacteria, Lactobacillus and Escherichia coli were higher than those in casein acid hydrolysate group after 12 h incubation in ileum. For the gut wall bacteria:in duodenum and ileum, after 12 h incubation, the concentration of microbial protein in the casein enzymatic hydrolysate group was higher than that in casein acid hydrolysate group (P<0.05). The number of Lactobacillus and Firmicutes in the casein enzymatic hydrolysate group was higher than those in the casein acid hydrolysate group in duodenum (P<0.05) and the number of Firmicutes was higher in the casein enzymatic hydrolysate group than that in the casein acid hydrolysate group in ileum. (P<0.05).[Conclusion] Compared with casein acid hydrolysate, casein enzymatic hydrolysate can promote the bacterial protein synthesis and stimulate the growth of Firmicutes in duodenum and ileum.