A mixture of milk and vegetable lipids in infant formula changes gut digestion, mucosal immunity and microbiota composition in neonatal piglets
PurposeAlthough composition of infant formula has been significantly improved during the last decade, major differences with the composition and structure of breast milk still remain and might affect nutrient digestion and gut biology. We hypothesized that the incorporation of dairy fat in infant formulas could modify their physiological impacts by making their composition closer to that of human milk. The effect of milk fat and milk fat globule membrane (MFGM) fragments in infant formulas on gut digestion, mucosal immunity and microbiota composition was evaluated.MethodsThree formulas containing either (1) vegetable lipids stabilized only by proteins (V P) (2) vegetable lipids stabilized by a mixture of proteins and MFGM fragments (V M) and (3) a mixture of milk and vegetable lipids stabilized by a mixture of proteins and MFGM fragments (M M) were automatically distributed to 42 newborn piglets until slaughter at postnatal day (PND) 7 or 28, and compared to a fourth group of sow's suckling piglets (SM) used as a breast fed reference.ResultsAt both PND, casein and b lactoglobulin digestion was reduced in M M proximal jejunum and ileum contents compared to V P and V M ones leading to more numerous b Cn peptides in M M contents. The IFNg cytokine secretion of ConA stimulated MLN cells from M M piglets tended to be higher than in V P ones at PND 7 and PND 28 and was closer to that of SM piglets. No dietary treatment effect was observed on IL 10 MLN cell secretion. Changes in faecal microbiota in M M piglets resulted in an increase in Proteobacteria and Bacteroidetes and a decrease in Firmicutes phyla compared to V P ones. M M piglets showed higher abundances of Parabacteroides, Escherichia/Shigella and Klebsiella genus.ConclusionsThe incorporation of both milk fat and MFGM fragments in infant formula modifies protein digestion, the dynamic of the immune system maturation and the faecal microbiota composition.
European Journal of Nutrition