The effect of bile acids on lipid research was examined in meat-type chicks, 8 weeks of age, with cannulated cystic and hepatic ducts. The procedure allowed for biliary collection in free-roving birds. Shams retained 90 to 92% dietary fat and those with cannulated ducts retained 43 to 72%. Addition of .04, .08, or .16% cholic acid or .08% freeze-dried chicken bile did not improve lipid retention significantly. The percentage retained for tallow and corn oil was 57 and 64%, respectively, far less then the 75 and 90% values, respectively, obtained in normal chickens. Neither practical-type nor purified-type diets, saturated (tallow) nor unsaturated (corn oil) fats at 8% of the diet significantly influenced lipid retention in chickens with cannulated ducts. In these chickens, percent dry matter retained of the purified diet was 81%, a significantly higher value than the 62% retained of the practical-type diet.