To evaluate the body composition, and to identify measurable body characteristics capable to estimate the relative size of body components, 36 young bulls (12 Nellore, 12 ½ Holstein x ½ Zebu, and 12 ½ Caracu x ½ Cebu) were used. In each genetic group, six animals of each production phase were used: growing animals with initial weight of 225 kg and the finishing ones with initial weight of 330 kg. The animals were maintained in confinement regime to reach 310 to 340 kg of weight for the growing animals and 420 to 470 kg of weight for the finishing ones. The same diet was fed to all the animals, with concentrate level of 50% in the dry matter and 50% of coastcross hay. A general factor of .8693 was adopted to conversion of live weight in empty body weight (obtained with the records of all the animals in the experiment). Animals from a beef selection origin, in finishing group, presented higher dressing percentage (59.2%) that those of milk selection origin (56.33%). Genetic groups originating from breeds with milk aptitude showed higher relative sizes of organs (9% more), 21% smaller total fatty tissue in carcass, as well as higher participation of internal fatty tissue in total fatty tissue. Despite of the low correlations, it is not reliable to estimate the relative sizes of the body components studied from the analyzed measurable body characteristics.
carcass; commercial cuts; physical composition; Nellore; crossbred
