Carcass characteristics of steers of different genetic predominance fed diets containing levels of substitution of corn grain by millet grain

This study aimed to assess the carcass characteristics of European crossbred young bulls or Zebu feedlot finished with diets with high percentage of concentrate (80%) containing different levels of pearl millet grain as replacement for corn grain (0, 33, 66 and 100%). Forty-five young bulls with genotype predominance of Aberdeen Angus and forty-four young bulls with genotype predominance Nellore with average initial weight of 317.8 and 320.7 kg, respectively, and average age of 21 month, were allocated in 16 collective pens. At the end of the finishing period were slaughtered six animals of each genetic group, chosen according to the body weight and degree of finishing each treatment. The experimental design was the completely randomized design with treatments in a 4x2 factorial arrangement using six replicates. The replacement of corn grain by millet grain did not significantly influence slaughter weight (480.4 kg), hot carcass weight (259.5 kg), carcass yield (54.1%) and subcutaneous fat thickness (3.95 mm). Young bulls with genotype predominance of Aberdeen Angus showed significantly higher values for slaughter weight (507.6 vs. 453.3 kg), hot carcass weight (269.6 vs. 249.3 kg) and longissimus dorsi area (65.34 vs 56.83 cm(2)), however, were lower in carcass yield (53.2 vs. 55.0%). Millet grain can be used in substitution to corn grain for finishing steers since it does not change carcass traits of economic interest.