Gut microbiota of healthy Canadian infants: profiles by mode of delivery and infant diet at 4 months

MB Azad, T Konya, H Maughan, DS Guttman, CJ Field… - Cmaj, 2013 - Can Med Assoc
Cmaj, 2013Can Med Assoc
Background: The gut microbiota is essential to human health throughout life, yet the
acquisition and development of this microbial community during infancy remains poorly
understood. Meanwhile, there is increasing concern over rising rates of cesarean delivery
and insufficient exclusive breastfeeding of infants in developed countries. In this article, we
characterize the gut microbiota of healthy Canadian infants and describe the influence of
cesarean delivery and formula feeding. Methods: We included a subset of 24 term infants …
Background
The gut microbiota is essential to human health throughout life, yet the acquisition and development of this microbial community during infancy remains poorly understood. Meanwhile, there is increasing concern over rising rates of cesarean delivery and insufficient exclusive breastfeeding of infants in developed countries. In this article, we characterize the gut microbiota of healthy Canadian infants and describe the influence of cesarean delivery and formula feeding.
Methods
We included a subset of 24 term infants from the Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort. Mode of delivery was obtained from medical records, and mothers were asked to report on infant diet and medication use. Fecal samples were collected at 4 months of age, and we characterized the microbiota composition using high-throughput DNA sequencing.
Results
We observed high variability in the profiles of fecal microbiota among the infants. The profiles were generally dominated by Actinobacteria (mainly the genus Bifidobacterium) and Firmicutes (with diverse representation from numerous genera). Compared with breastfed infants, formula-fed infants had increased richness of species, with overrepresentation of Clostridium difficile. Escherichia–Shigella and Bacteroides species were underrepresented in infants born by cesarean delivery. Infants born by elective cesarean delivery had particularly low bacterial richness and diversity.
Interpretation
These findings advance our understanding of the gut microbiota in healthy infants. They also provide new evidence for the effects of delivery mode and infant diet as determinants of this essential microbial community in early life.
Can Med Assoc