Research Note: A Comparison of Methods to Determine the Metabolizable Energy of Feather Meal

Metabolizable energy values of a feather meal sample were compared using four different assay techniques. One variation of the classical chick assay (substitution for basal diet, full-fed chicks, 0 to 14 days of age, chromic oxide indicator) gave 2.34 ± .08 kcal MEn/g dry matter when substituted into the reference diet at 400 g/kg, and 2.83 ± .12 kcal/g at 200 g/kg. A second MEn variation (substitution for basal diet, full-fed chicks, 7 to 14 days of age, total excreta collection) gave a value of 2.77 ± .04 kcal/g when substituted into the reference diet at 400 g/kg. Values from Sibbald’s (1986) TMEn and Farrell’s (1978) AMEn assays using adult cockerels were 3.34 ± .09 and 3.42 ± .10 kcal/g, respectively. Values derived from the two rapid cockerel assays were essentially the same but higher than those from the classical type of assay with ad libitum-fed chicks.