Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Foi avaliada a composiÃÃo relativa dos cortes comerciais da carcaÃa e a composiÃÃo tecidual (mÃsculo, osso e gordura) da perna, lombo e paleta de cabritos mestiÃos Boer, Anglo Nubiano e os do tipo sem raÃa definida (SPRD), esse Ãltimo usado como grupo controle. Foram utilizados 44 caprinos, sendo 20 de diferentes graus de sangue Anglo Nubiano x SPRD (13  Anglo Nubiano x  SPRD e 07  Anglo Nubiano x  SPRD), 16 Boer x SPRD (07  Boer x  SPRD e 09  Boer x  SPRD) e 8 cabritos SPRD. Os animais foram abatidos, em mÃdia, com 12 meses de idade e 30 kg de peso vivo. ApÃs resfriamento (2ÂC) da carcaÃa por 24 horas, foram separados os seguintes cortes comerciais: perna, lombo (anterior e posterior), paleta, peito, costela, pescoÃo e fraldinha, sendo obtidos os rendimentos em relaÃÃo ao peso da carcaÃa fria. Em seguida, a perna, o lombo (anterior e posterior) e a paleta foram dissecados, separando-se os tecidos muscular, adiposo e Ãsseo. A partir dos pesos desses tecidos, foram estimadas as relaÃÃes mÃsculo:osso (RMO) e mÃsculo:gordura (RMG). O desenho experimental obedeceu a um delineamento inteiramente casualizado, e os dados foram analisados pelo procedimento GLM do pacote estatÃstico SAS, em que as mÃdias foram comparadas pelo teste de Tukey. Os rendimentos mÃdios dos cortes foram: perna = 29,8%, lombo = 24,7% (anterior = 18,3% e posterior = 6,4%), paleta = 20,8%, peito = 5,0%, pescoÃo = 7,16%, costela = 3,3% e fraldinha = 5,8%, sem que tenham sido observadas diferenÃas significativas (P>0,05) entre os grupos genÃticos para os cortes estudados, exceto para costela e pescoÃo. Nos cabritos mestiÃos Boer, observaram-se rendimentos superiores (P<0,05) no tecido muscular (64,88%) e na RMO (5,40). Jà nos cabritos mestiÃos Anglo Nubiano, observou-se rendimento superior (P<0,05) para o tecido adiposo (9,46%), enquanto os cabritos SPRD apresentaram superioridade no rendimento do tecido Ãsseo (21,35%) e na RMG (10,5). Conclui-se que, nos cortes de maior valor comercial, a carcaÃa de cabritos mestiÃos Boer apresenta uma maior proporÃÃo de tecido muscular que os cabritos mestiÃos Anglo Nubiano e os SPRD / In this study, the relative composition of the commercial cuts of the carcass and the tissue composition (muscle, bones and fat) of the thigh, loin and shoulders of half-blooded Boer, Anglo Nubian and undefined-breed kids (SPRD) were evaluated. The SPRDâs were used as control group. Forty-four pieces were used, of which 20 units of mixed-blooded Anglo Nubian x SPRD (13  Anglo Nubian x  SPRD and 7  Anglo Nubiano x  SPRD), sixteen Boer x SPRD (07  Boer x  SPRD and 09  Boer x  SPRD), and the remaining 8 heads being SPRDâs. The animals were slaughtered at the average age and weight of 12 months and 30 kg respectively live weight. After cooling the carcass at 2 degrees centigrade for 24 hours the following commercial cuts were set apart: thigh, loin ( front and hind ) shoulders, breast, ribs, neck, sirloin and the proportional weights were figured out in relation to the total weight of the cold carcass. Next, the thigh, loin (front and hind) and shoulders were dissected and the relationship between the weight of the cold carcass and yield was determined, setting apart the muscular, bone and grease tissues. From the weights of such tissues the relations muscle/bones (RMB) and muscle/fate (RMF) were estimated. The experimental scratch was designed in an entirely random way and the data was analyzed according to the GLM procedures in the SAS statistics package in the which the measurements were compared according to the Tukey test. The average yield of the cuts was: tight 29.8%, loin 24.7% ( front 18.3% and hind 6.4%), shoulders 20.8% , breast 5.0%, neck 7.16%, ribs 3.3%, sirloin 5.8%. No significant differences (P>0.05) were found among the genetic groups studied except for the neck and ribs. In the Boer mixed blooded animals higher yield (P>0.05) in the muscular tissues (64.88 %) and in RMB (5.40%) were absorbed. The Anglo Nubian mixed blooded animals showed a higher yield (P<0.05) in the grease tissues (9.46 %), whereas the SPRDâs showed a superior yield in the bone tissue (21.35%) and in the RMF (10.5). The conclusion was that in the cuts of greater commercial value, the carcass of Boer mixed shows a better yield of muscular tissue than the Anglo Nubian and SPRDâs half breeds