The objective ofthis work was to analyze the interrelations among weights and carcass measuresof the longissimus lumborum muscle thickness and area, and of sternumtissue thickness, measured directly on carcass and by ultrasound scan. Measureswere taken on live animals and after slaughter to develop models of multiplelinear regression, to estimate the composition of shoulder blade, from selectedvariables in 89 kids of both genders and five breed groups, raised in feedlotsystem. The variables considered relevant and not redundant on the informationthey carry, for the common factor analysis, were used in the carcass compositionestimate development models. The presuppositions of linear regression modelsrelative to residues were evaluated, the estimated residues were subjected toanalysis of variance and the means were compared by the Student t test. Basedin these results, the group of 32 initial variables could be reduced to fourvariables: hot carcass weight, rump perimeter, leg length and tissue heightat the fourth sternum bone. The analysis of common factors was shown as an effectivetechnique to study the interrelations among the independent variables. The measuresof carcass dimension, alone, did not add any information to hot carcass weight.The carcass muscle weight can be estimated with high precision from simple models,without the need for information related to gender and breed, and they couldbe built based on carcass weight, which makes it easy to be applied. The fatand bones estimate models were not as accurate.
