Quantitative PCR of samples from Experiment C. Relative amount of target gene in samples from animals in the control group (black), the pectin-fed group (white) and the apple-fed group (gray). Target genes encoded either 16S rRNA from Bacteroides spp. (a), Lactobacillus (b), Bifidobacterium (c), Clostridium coccoides (d) or the butyryl-coenzyme A CoA transferase. DNA amount in the control group was set to 100%. Error bars represent standard errors of the means. Asterisks indicate a significant difference from the control group; P < 0.05 (*) or P < 0.01 (**).