Fig 1. Microbiome composition of human milk samples.

(A) Infant age (days) at time of sampling, relative abundance, maternal antibiotics in the 14 days prior to sampling, mode of delivery, and Shannon diversity of human milk samples from mothers with infants who either have latched or never latched. Samples from the same mother collected on different days are grouped. Milk from mothers who never had their infants latched were dominated by Staphylococcus in one and Staphylococcus, Finegoldia and Corynebacterium in the other. Note the absence of Streptococcus and lower overall diversity of never-latched samples. In contrast, samples from mothers with latched infants, also born via Caesarian section in the first 10 days of life (n = 5), contained Streptococcus, Acinetobacter, and Enterobacter in addition to Staphylococcus. (B) Relative abundance of genus Bifidobacterium by targeted 16S rRNA gene sequencing (left) and shotgun metagenomics (right) in a single milk sample (arrow) shown in Panel A. Bifidobacterium breve appears to be selectively cultivated in the mother’s milk and then makes up the majority of her infant's early gut microbiome.