Diarrhea is a leading cause of morbidity and mortality in infants. The addition of fiber to infant formulas reduces recovery time following pathogenic
infection in infants > 6 mo old, but effects on neonates are unknown. The hypothesis that fermentable fiber reduces
infection-associated symptoms and enhances intestinal structure and function in neonates was examined. Piglets (2 d old) were randomly assigned to receive formula alone (control) or formula containing
methylcellulose (MCEL), soy
polysaccharides (SPS) or fructooligosaccharides (FOS) for 14 d. On d 7, piglets were further randomly assigned to receive an oral gavage of Salmonella typhimurium or serve as noninfected controls. S. typhimurium
infection produced
diarrhea in controls and MCEL groups, but not in the SPS and FOS groups. Postinfection physical activity was lower (P = 0.0001) in the controls than in all other groups. Ileal
lactase activity was reduced (P < 0.05) following
infection in the control group but not in the MCEL, SPS and FOS groups. Ileal mucosal barrier function, measured as resistance, was impaired by
infection (P < 0.05) in the control and SPS groups, but was unaltered in the jejunum and colon. Total ion transport and basal short-circuit current were higher (P < 0.05) in jejunum than in ileum and colon, irrespective of diet or
infection. SPS and FOS increased (P < 0.05) ileal
glutamine transport relative to piglets fed MCEL, irrespective of
infection. Because fermentable fiber enhances intestinal function and reduces the severity of S. typhimurium
infection-associated symptoms, it may be a cost-effective way in which to reduce the severity of pathogenic
infection-associated symptoms in infants.