Growth performance in feedlot and carcass characteristics of beef cattle from several crossbreds slaughtered in three body weight ranges

This work was conducted to evaluate performance and carcass characteristics of feedlot beef cattle from three straightbred genetics groups of cattle (NE1 - Nellore; NE2 - Nellore from the Agropecuaria CFM Ltda. and HOL - Holstein) and nine Nellore crossbred genetics groups (SD2 -(1)/(2) South Devon; HE2 -(1)/(2) Hereford; AA2 -(1)/(2) Aberdeen Angus; CA2 -(1)/(2) Caracu; RA2 -(1)/(2) Red Angus; L12 -(1)/(2) Limousin; SI4 -(1)/(4) Simmental; CH4 -(1)/(4) Charolais e LI4 -(1)/(4) Limousin),and only RA2 and LI2 genetics group were composed by castrated animals. Each group had 12 animals and they were allocated into three slaughter groups (67, 117 and 151 days from beginning of the trial). Animals from SI4 and SD2 groups presented larger slaughter body weight at 151 days than animals from the NE1 and NE2 groups. Animals from NE, group presented smaller overall average weight gain. The genetic group LI2 showed the major percentage of hindquarter and the animals from AA2 group showed the smallest one. The percentage of kidney and pelvic fat (GRPI) was larger for animals from RA2 group and smaller for HE2 group. The castrated animals showed smaller percentage of forequarter. The animals with small body size presented larger GRPI in the three slaughter body weight ranges.