The nitrogen-corrected apparent (AMEn) and true (TMEn) metabolizable energy values of a low-fat and a high-fat meat meal (MM) were studied. Adult roosters were fed ad libitum on a basal diet or a mixture of the basal diet and one of the two MM. At up to 60% incorporation, MM were introduced at the expense of corn in the basal diet. Dietary inclusion was at 5, 10, 20, 40, and 60%; birds were also force-fed pure MM. The ME of MM decreased as MM content in the diet increased. Highest AMEn were observed when the MM was 5% of the diet (3356 and 1715 kcal/kg for the high- and low-fat MM, respectively); this may have been attributable to synergism of MM and basal diet fatty acids. The lower ME observed with higher MM could result from interactions between calcium and one or both fatty acids and proteins. It is concluded that ME of MM should be measured in diets containing low practical MM. Artificially high experimental levels of 50 or 100% may lead to underestimation of the energy of MM.