Addition of polydextrose and galactooligosaccharide to formula does not affect bacterial translocation in the neonatal piglet.

OBJECTIVES: The aim of the study was to determine the effect of polydextrose (PDX) and galactooligosaccharide (GOS) on bacterial translocation (BT) in neonatal piglets. MATERIALS AND METHODS: Piglets (n = 36) were randomized 12 hours after birth to receive total enteral nutrition (TEN) as formula; TEN + GOS (4 g/L), TEN + PDX (4 g/L), or TEN + GOS + PDX (2 g/L each) for 7 days or were supported by total parenteral nutrition (TPN) as a positive control for BT (n = 8). Blood, spleen, liver, and mesenteric lymph node (MLN) samples were cultured for aerobic and anaerobic bacteria. Colon microbiota 16S rDNA was measured by polymerase chain reaction. Myeloperoxidase activity and tumor necrosis factor-α expression were measured in ileum and ascending colon. RESULTS: Among the enterally fed groups, no difference was seen in the Lactobacillus and Bacteroides 16S rDNA copies per gram of colonic contents, yet total bacterial levels were lower (P < 0.05) in the TEN + GOS group compared with TEN alone. Bacteria were detected in the blood, liver spleen, and MLN of TPN piglets. In contrast, bacterial counts were predominantly detected in the MLN of TEN piglets, at much lower levels than in TPN, and levels were not affected by GOS and PDX addition. TPN piglets had elevated (P < 0.05) ileal myeloperoxidase activity and a trend in elevated ascending colon tumor necrosis factor-α expression (P = 0.1). CONCLUSIONS: PDX and GOS added to formula do not induce BT in healthy piglets. Low levels of bacteria in MLN of healthy neonatal piglets may reflect mucosal sampling rather than pathological BT.

Characterization of the Intestinal Lactobacilli Community following Galactooligosaccharides and Polydextrose Supplementation in the Neonatal Piglet.

Recently, prebiotic supplementation of infant formula has become common practice; however the impact on the intestinal microbiota has not been completely elucidated. In this study, neonatal piglets were randomized to: formula (FORM, n = 8), formula supplemented with 2 g/L each galactooligosaccharides (GOS) and polydextrose (PDX, F+GP, n = 9) or a sow-reared (SOW, n = 12) reference group for 19 days. The ileal (IL) and ascending colon (AC) microbiota were characterized using culture-dependent and -independent methods. 16S amplicon sequencing identified no differences at the genera level in the IL. Interestingly, six genera in the AC were significantly different between FORM and F+GP (P<0.05): Lactobacillus, Ruminococcus, Parabacteroides, Oscillospira, Hydrogenoanaerobacterium and Catabacter. In particular, the relative abundance of AC Lactobacillus was higher (P = 0.04) in F+GP as compared to FORM. Culture-dependent analysis of the IL and AC lactobacilli communities of FORM and F+GP revealed a Lactobacillus spp. composition similar to 16S amplicon sequencing. Additional analysis demonstrated individual Lactobacillus isolates were unable to ferment PDX. Conversely, a majority of lactobacilli isolates could ferment GOS, regardless of piglet diet. In addition, the ability of lactobacilli isolates to ferment the longer chain GOS fragments (DP 3 or greater), which are expected to be present in the distal intestine, was not different between FORM and F+GP. In conclusion, prebiotic supplementation of formula impacted the AC microbiota; however, direct utilization of GOS or PDX does not lead to an increase in Lactobacillus spp.