FIGURE 2.

Box and whisker plots demonstrating the changes in (A) the number of observed OTUs, (B) the abundance of Ruminococcaceae UCG-005, and (C) the abundance of Ruminococcaceae UCG-014 associated with piglet age and the interaction with birthweight class [low (LBW) or normal (NBW)]. (A) Significant pairwise differences in observed OTUs associated with the interaction between birthweight classes and piglet age are identified by differences in the assigned Tukey HSD letters: days 4LBW^a, 4NBW^ab 8LBW^b, 8NBW^bc, 14LBW^cd, 14NBW^d, 21LBW^d, 21NBW^g, 27LBW^h, 27NBW^g, 32LBW^fg, 32NBW^d, 35LBW^d, 35NBW^d, 42LBW^d, 42NBW^de, 49LBW^ef, 49NBW^ef, 56LBW^g and 56NBW^f. (B). Significant differences in Ruminococcaceae UCG-005 abundance associated with increasing piglet age and the interaction with birthweight classes (LBW or NBW) are identified by differences in the assigned Tukey HSD letters: days 4LBW^ab, 4NWB^a, 8LWB^abc, 8NBW^cdef, 14LBW^def, 14NBW^def, 21LBW^cd, 21NBW^f, 27LBW^ef, 27NBW^def, 32LBW^def, 32NBW^bcd, 35LBW^cdef, 35NBW^cdef, 42LBW^def, 42NBW^def, 49LBW^cde, 49NBW^def, 56NBW^def and 56LBW^def (C). Significant differences in Ruminococcaceae UCG-014 abundance associated with increasing piglet age and the interaction with birthweight classes (LBW or NBW) are identified by differences in the assigned Tukey HSD letters: days 4LBW^ab, 4NWB^a, 8LWB^abc, 8NBW^abcd, 14LBW^abcd, 14NBW^abcd, 21LBW^bcd, 21NBW^cde, 27LBW^def, 27NBW^def, 32LBW^f, 32NBW^abcd, 35LBW^def, 35NBW^def, 42LBW^f, 42NBW^ef, 49LBW^f, 49NBW^f, 56LBW^f and 56NBW^f. The number of sample replicates for each group are presented in Supplementary Table S2.