Individual and Combined Effects of 2’fucosyllactose and Bifidobacterium Longum Subsp. Infantis on the Gut Microbiota Composition of Piglets

Human milk is a source of oligosaccharides that promote the growth of beneficial bacteria. Bifidobacterium longum subsp. infantis, a dominant species in breastfed infants, has the capacity to utilize milk oligosaccharides. Herein, the effects of 2'fucosyllactose (2'FL), B. infantis Bi-26 (Bi-26), and a combination thereof on piglet gut microbiota composition and volatile fatty acid (VFA) concentrations were assessed. Fifty-two intact male pigs were provided ad libitum access to a nutritionally-adequate milk replacer without (CON) or with 1.0 g/L 2’FL (FL) from postnatal day 2 to 34/35. Pigs were further stratified to receive either 12% glycerol or Bi-26 in glycerol orally, 109 colony-forming unit/day (BI and FLBI). Ascending colon (AC) and rectal contents were collected. Gut microbiota profiles were assessed by 16S rRNA gene sequencing and real-time PCR and VFA were determined by gas chromatography. Neither 2'FL nor Bi-26 affected the overall microbiota composition (P > 0. 05); however, alpha diversity and the relative abundances of bacterial genera were influenced by the treatments. Shannon indices were lower in AC of piglets fed Bi-26 (P = 0.048). Proportions of Clostridia UCG-014, Lachnoclostridium, Christensenellaceae R-7 group and Anaerovoracaceae family XIII AD3011 group were lower, while Faecalibacterium was higher in AC of piglets receiving 2'FL (P < 0.05). Bi-26 decreased (P < 0.05) colonic abundances of Parabacteroides, Fusobacterium, Butyricimonas and uncultured Prevotellaceae. In rectal contents,7 bacterial genera were impacted by 2'FL and 3 by Bi-26 (P < 0.05). Interactive effects were observed for several bacterial genera and acetate concentrations (P < 0.05). In AC, Lachnospiraceae CAG-56 was higher in CON than all other groups and Allisonella was lower in BI piglets vs. CON. Rectal contents Bacteroides was higher in BI piglets than CON. Compared to CON, acetate concentrations were higher in AC of FL piglets (P < 0.05). 2'FL and Bi-26 supplemented to milk replacer exerted individual and synbiotic influences on gut bacterial composition, and 2'FL alone increased specific VFA concentration, demonstrating its prebiotic potential. DuPont Nutrition and Biosciences.