The effects of inulin, dried Jerusalem artichoke tuber and a multispecies probiotic preparation on microbiota ecology and immune status of the large intestine in young pigs.

The study aimed at determining the effect of two types of prebiotics and a multispecies probiotic on microbiota activity and composition, as well as mucosal immunity in the large intestine of young pigs. In total 48 piglets were divided into 6 groups (n = 8), which received from day 10 of life probiotic-unsupplemented (PU) or probiotic-supplemented (PS) diets. Probiotics were added at 0.5 g/kg diet and contained: Lactococcus lactis, Carnobacterium divergens, Lactobacillus casei, Lactobacillus plantarum and Saccharomyces cerevisiae. The PU and PS diets were formulated without prebiotic addition (control) or with addition of 2% of inulin from chicory root (IN) or 4% of dried Jerusalem artichoke tubers (DJA). After 40 days of feeding, digesta and tissue samples were taken from the caecum and three sections of the colon for analyses of microbiota activity and composition, secretory immunoglobulin A (sIgA) and intraepithelial lymphocytes (IEL). IN diets decreased the caecal digesta pH and β-glucosidase activity but increased propionic, valeric and total short chain fatty acid (SCFA) concentrations compared to control diets. Feeding DJA diets increased caecal valeric acid level, decreased the concentration of isoacids in the colon, reduced β-glucosidase and β-glucuronidase activity in the middle colon and increased Bifidobacterium spp. populations in the proximal and distal colon. PS diets increased the caecal acetic acid and total SCFA level, and Clostridium spp. populations in the distal colon. Neither probiotic nor prebiotics affected sIgA level or IEL number in the large intestine. In conclusion, DJA modified the microbiota ecology in the large intestine of young pigs to a greater extent than IN and the applied probiotic did not enhance effects of prebiotics.