Microbiota progression before early onset NEC and late onset NEC at class and genus level.

<p>The relative abundances of four most dominant classes (Fig. 3A-early onset at class level, 3B-late onset at class level) and the genera (Fig. 3C-early onset at genus level, 3D-late onset at genus level) that are significantly different between NEC and controls are plotted at 7–9 days, 4–6 days and 1–3 days prior to NEC onset. In early onset NEC category, 3,6, 8 NEC samples were included at 7–9 days, 4–6 days and 1–3 days; 8, 5, 6 control samples were included in the above time points. In late onset NEC category, 7, 7,10 NEC samples and 6, 8, 4 control samples were included in the above time points. Red and green of the boxplots indicate NEC and control samples, respectively. The asterisks indicate the significant difference between NEC and control.