The apparent metabolizable energy (AME) values of samples of corn, wheat, rye, oats, barley, and of fish, feather, meat, soybean, sunflower, rapeseed, and dehydrated alfalfa meals were measured by two chick bioassays. For the AMES bioassay, each test feedingstuff was mixed with a basal diet at four levels of inclusion. For the AMEH bioassay, glucose monohydrate was replaced in a basal diet by each of the 12 test feedingstuffs. Chromium sesquioxide (Cr2O3) was added to all diets; Cr2O3 and acid insoluble ash were used as internal indicators. The AMES results were calculated by regression analysis and by solution of simultaneous equations.The AME results showed that AMES values were larger than AMEH values (P<.05) for barley and protein supplements. The method of calculation of AMES results had a big effect on the values for meat, feather, and fish meals; there was a lack of linearity between level of inclusion of test material and AMES values of these feedingstuffs. The AME data appeared to be independent of the internal indicator measured during the bioassay. A comparison of the AME results presented here with TME and AME data reported elsewhere cast doubt upon the usefulness of published AME values.