Study on true metabolizable energy values of feed ingredients and complete feed in the meat type crossbred chickens

Study on true metabolizable energy (TME) and nitrogen corrected TME (TME n) of feedstuffs for meat type crossbred chickens was conducted in two experiments. Experiment 1. Each sex was separated into 6 groups, 3 birds to a group. The birds were starved for 24 hrs to empty thier digestive tract. Except for the first group, all others were forced fed 30 grams of feedstuff by insert tube funnel into the crop. The feces were collected quantitatively for exactly 24 hrs, and were dried in hot air oven at 60 deg C for 18 hrs. Finally, the dried feces were assayed for quantity nitrogen and gross energy. The TME and TME n values of fish - meal, soybean - meal, corn, ricebran and tallow were 3460, 3572, 4166,. 3330, 8532 and 3006, 2995, 4132, 3220, 9030 Kcal/kg (DM), respectively. However, there are no significant differences between sexes (P0.05). In experiment 2. The work was conducted the same as in experiment 1 except that the treatment was changed to complete feed. The birds were forced fed 10 grams of starter diet, 20 grams of grower and finisher diet at 3 6 and 8 weeks of age, respectively. The TME - TME n values were 4426-3850 4040-3796 and 3959-3807 Kcal/Kg (DM). respectively. Experiment 3. A 3 * 3 Factorial in Randomized Complete Block Design, consisting of 3 levels of energy 3280-3400-3520 3260-3380-3500 3280-3400-3520 Kcal/Kg (TME n, air dry basis) and 3 levels of protein 23.50-22.50-21.50 20.50-19.50-18.50 19.50-18.50-17.50 percent were used for 0-3 3-6 and 6-8 weeks of age, respectively. It was found that the protein level had no effect on performance (P0.05) at 0-8 weeks. The energy (TME n) of 3400 and 3520 Kcal/Kg resulted in average body weight gain and feed intake increase more than 3280 Kcal/Kg (P0.05) at 0-3 weeks but at 3-8 weeks it showed no sinificant difference (P0.05). Interaction of energy levels and protein levels produced no effect on performance at 0-6 weeks, but the energy of 3520 Kcal/Kg (TME n) with 18.50 percent protein revealed average body weight gain and feed conversion better than others (P0.05) at 6-8 weeks.