Growing Japanese quail at 35 days o f the experiment, weighed respectively, as follows when fe d the various levels o f a test vitamin in their diet: (a) thiamin hydrochloride (mg/kg diet), 1, 1.5, 2, 2.5, 3, and 3.5; body weight (g), 68.5, 94.8, 105.7, 103.3, 99.4 and 97.4. (b) Riboflavin (mg/kg iet), 0.75, 1, 1.5, 2, 2.5, and 3; body weight (g), dead, 45.3, 72.6, 103.0, 100.2 and 103.9. (c) ridoxine hydrochloride (mg/kg diet), 1, 1.5, 2, 2.5, 3, and 3.5; body weight (g), 91.9, 101.6, 102.5, 105.9, 05.7, and 103.2. (d) niacin (mg/kg diet), 5, 10, 15, 20, 25, and 30; body weight (g), 93.8, 100.8, 105.2, 106.8, 101.9, and 109.4. The dietary supplements for growing Japanese quail are estimated to be as follows (mg/kg diet): thiamin hydrochloride, 1.5; riboflavin, 2; pyridoxine hydrochloride, 1.5; and niacin, 15.