1. This experiment carried out to study the effects of dubbing, wing clipping and detailing on the growth rate, feed utilization and mortality of growing chicks. 2. This experiment were conducted out by the completely randomized block design at the Dept. of Livestock. Chin Zu Agricultural college for 8 weeks from March 24 to May 19, 1963. 3. Both sexes of white leghorn, day old chicks were reared in electric bulb heated hattery. Feed and water supplied by the self feeders and waters ad libitum, The chicks were leg banded and divided into 6 lots eqivalently according to the chick`s weight. The basal diet was composed with 15% Yellw corn, 8% Broken rice, 20% Wheat ground, 5% Rice bran, 6% Wheat bran, 5% Millet, 15% Fish meal, 1.5% non-fat dry milk, 1.5% Red clover, 1.0% Bone meal, 1.4% Oyster shell, 0.6% Salts and added Antibiotic supplements in the ration of 10 grams Fer ton of feed, Vitamin. Mineral matter and Amino acid levels of basal diet were calculated and accorded with N. R. C. feeding standard. Following table shows both number of birds and treated methods in this experiment. 4. Individual chick weights, feed consumptions and mortalities were recorded for 8 weeks. The growth rate of each lets were expressed is two different kinds weights which added and non added the weights of treated parts. Both growth rates were treated statistically by the analysis of variance of Kramer`s multiple range test. 5. Discussions of experimental results; 1) It has shown a least significant range by the methods of kramer`s multiple range test on the treated results that the L. S. R. (P$lt;0.05) in difference between T_5 to C₁ and T₄ to C₁ in the added body weight at 8weeks age, on the other hand, T_5 to C¹ had shown a L. S. R. (P$lt;0.05) in the non added weights. 2) Comparing the feed utilities of this experiment on the average feed consumption required per gram of gain weights were following; 2.97 in C₁, 2.96 in T₁, 2.89 in T₂, 3.12 in T₃, 2.76 in T₄ 2.85 in T_5. 3) Mortality of this trials had shown as following; 17.1% in C₁, 10.0% in T₁, 20.0% in T₂, 23.39 in T₃, 20.0% in T₄, 16.6% in T_5. 4) From the results of above mentioned, it seems to have an effective results to the broiler production because T₄ aid T_5 Lots had been good results on the growth rate and feed consumption by the detailing and wing clipping treatments. $lt;표생략$gt;