Dynamic changes of gut microbiota associated with blood glucose levels in sows from pregnancy through lactation

Gut microbiota plays important roles in metabolism and physiological homeostasis throughout the lifespan of mammals, including in pregnancy. To evaluate the effects of practically adopted restricted feeding during gestation on blood glucose level and fecal microbiota composition, 31 sows were used to identify the shifts in bacterial assemblages by 16S rRNA sequencing in their early pregnancy, late pregnancy and late lactation stages. We find that the blood glucose was elevated significantly (p < 0.001) in sows offered abundant feed in the late lactation as compared with those of the same cohort in the pregnancy stages when on limited feed. Five bacterial genera were differentially abundant among three stages, and the abundances of Streptococcus (padj < 0.001) and unclassified_f_Lachnospiraceae (padj < 0.001) were increased, whereas the abundances of Lactobacillus (padj = 0.035) and Escherichia-Shigella (padj< 0.001) were decreased in the latter two stages. The genus Prevotellaceae_NK3B31_group (padj = 0.026) displayed higher abundance in the late lactation stage. A significant correlation in the Pearsons analysis indicates that three out of these five differentially abundant genera were related to blood glucose change. Our data show that restricted-fed gestating sows have aberrant blood glucose level and may affect the intestinal microbiota.