Fig. 4

Principal component analysis of the metabolomic data at T1. Scatter plot visualising the principal components of the unsupervised principal component analysis (PCA) of the metabolomic data from the samples collected on day 16 ± 0.6 (T1) of age before (a) and after (b) the removal of outliers. Each data point is represented by its coordinates in the first and second principal components. The data points belonging to the normal pigs (NORM) are plotted in blue, and those belonging to pigs affected by intrauterine growth restriction (IUGR) are plotted in red. Samples do not group together according to the IUGR/NORM status in the scatter plot of the PCA first principal plan