**3.2. Chemical analysis of diets and excreta**

The experimental diets and the excreta were milled (0.75 mm mesh) and analysed further. Dry matter (DM) was determined by drying samples in a forced draft oven at 105°C to a constant weight. Crude protein (6.25 × N) in samples was determined by dry combustion method [33] using a LECO (FP-528 N, Leco Corp., St. Joseph, MI). Oil (as ether extract) was extracted with diethyl ether by the ether extraction method [33], using a Soxtec system (Foss UK Ltd.). The GE value of the samples was determined in a bomb calorimeter (model 6200; Parr Instrument Co., Moline, IL), using benzoic acid as the standard.
