Young female turkeys received diets containing Crotalaria spectabilis seeds for 18 weeks. Mean values for total bile flow, biliary bile acid excretion, bile acid-dependent flow and bile acid-independent flow were significantly higher in crotalaria-fed turkeys than in controls. The hypercholeresis observed in crotalaria-fed birds involved both bile acid-dependent and bile acid-independent components of bile. Crotalaria-fed turkeys developed biliary hyperplasia. Liver weights were similar in the two groups. Since increases in 14C-erythritol clearances paralleled increases in total bile flow in crotalaria-fed turkeys (14C-erythritol bile to plasma ratios were similar in both groups), it was evident that the hypercholeresis in crotalaria-fed turkeys did not involve the ductal/ductular component of bile. Little or no ductal/ductular bile flow occurred in either group since total bile flow was equal to erythritol clearance and extrapolation to zero erythritol clearance yielded zero bile flow rates in both groups. Crotalaria-fed turkeys exhibited significantly higher biliary concentrations of chlorides (associated with lower sodium , potassium and bicarbonate concentrations) than did control birds. Validation of the use of 14C-erythritol clearance for the estimation of canalicular bile flow in turkeys was provided both by substantial decreases in bile to plasma 14C-erythritol concentration ratios following the injection of avian vaso-active intestinal peptide and the failure to demonstrate chromatographically the presence of radioactive metabolites of 14C-erythritol in plasma.