Fecal bile salt excretion. Fecal bile salt excretion in (a) homozygous ΔF508 mice and (b) cystic fibrosis transmembrane conductance regulator (CFTR)-knockout mice and their respective wild-type (WT) littermates. Antibiotic (AB)-treated cystic fibrosis (CF) mice (hatched pattern) and their WT littermates (black); control-treated CF mice (gray) and their wild-type (WT) littermates (white). CA, cholic acid; DCA, deoxycholic acid; HDCA, hyoxydeoxycholic acid; MCA, muricholic acid. Values are depicted as mean ± SEM *P value <0.05, **P value <0.01.