Determination of nutrient digestibility, and apparent and nitrogen-adjusted metabolizable energy of paddy rice and brown rice for Luong Phuong chicken

Abstract

A trial was conducted with 210 Luong Phuong cockerels to investigate the digestibility of dry matter, protein, fat, fiber, minerals, nitrogen-free extract, and metabolizable energy value of IR50404 paddy rice and brown rice in the diet. Cockerels, averaging 558 g/bird, had their ceca removed and were randomly assigned to metabolic cages, with 3 dietary treatments and 5 replicates. The diets included: a basal diet; and two experimental diets containing 20% paddy rice and 60% brown rice in the basal diet. The trial lasted 7 days, in which a 4-day adaptation and a 3-day collection. Digestibility of individual paddy rice and brown rice in the experimental diets was calculated by difference method. Results indicated that digestibility of dry matter (range 72.8-74.11%), neutral detergent fiber (64.94-69.83%) and total ash (60.23-62.54%) were not different between paddy and brown rice (P>0.05); however, the digestibility of organic matter (87.52% vs 77.55%), crude protein (79.63% vs 72.31%), ether extract (79.74% vs 64.77%) and nitrogen-free extractives (46.42% vs 35.47%) in paddy rice were lower than those in brown rice (P<0.05). Paddy rice contained higher apparent metabolizable energy (3,212 vs 2,867 kcal/kg air DM) and nitrogen-adjusted metabolizable energy (3,014 vs 2570 kcal/kg air DM) than those in brown rice. In conclusion, brown rice contains higher nutritive value than paddy rice for broiler chicken, however, two feed ingredients can be a good energy source for poultry.