True Metabolizable Energy Estimates for Wild and Game-Farm Mallards

Abstract

Potential differences in metabolism of food energy by wild and game-farm mallards (Anas platyrhynchos) may confound assays for true metabolizable energy (TME) of foods fed to either strain of mallards. Consequently, we compared estimates of TME for a commercial diet between captive wild-strain and game-farm mallards. Mean values for body mass and TME were similar (P≥0.2) between mallard strains, but mean TME was slightly more variable for game-farm (CV=8.5%) than wild mallards (CV=5.9%). Our pooled mean estimate of TME (2.76±0.07 kcal/g) was similar to several other reported values for mallards fed a comparable diet, but intermediate among TME values of natural foods or cereal grains ( 3 kcal/g) consumed by Anas species