ABSTRACT This study investigated the effects of dietary protein levels and betaine supplementation on nutrient digestibility and performance of Japanese quails. In total, 765 Japanese quails were randomly assigned to a 3×3 factorial arrangement, with five replicates of 17 quails each. Three basal diets were formulated to contain three crude protein levels (16.5, 18.0, and 19.5%). Each protein level was supplemented with 0, 0.06, and 0.12% betaine. The diet with 16.5% dietary crude protein with no betaine supplementation resulted in the lowest crude fiber digestibility, while the 18.0% CP diet supplemented with 0.12% betaine generated the highest crude fiber digestibility (p<0.05). The diets with 18.0 and 19.5% crude protein increased crude fiber... |