Simultaneous biological trials were conducted with cocks and drakes to evaluate AME and TME of certain poultry feedstuffs to examine the species differences on the metabolizability of energy. Test ingredients were force-fed to four cocks and drakes each after 24 h of fasting, simultaneously, the control (unfed) groups in both the species were maintained for another 24 h on fasting. Excreta over a period of 24 h was quantitatively collected from all groups. The AME values (kcal/g) were significantly higher in drakes than cocks for maize (3.915 vs 3.585), rice broken (3.077 vs 2.862), deoiled rice bran (2.274 vs 1.866), sunflower cake (2.481 vs 2.145), de-oiled groundnut cake (2.784 vs 2.503) and soybean meal (2.780 vs 2.393). The endogenous excretory losses (EEL) were less in drakes than in cocks and as such the TME values followed a different pattern. The nitrogen correction had no significant influence on AME and TME. However, significant differences between ducks and chicken for both AME and TME values suggest that species variation do exist in the metabolizability of feedstuffs.
ME, AME, TME, species, EEL, drake, cock
