ABSTRACT - This experiment was conducted to evaluate the performance in feedlot finishing period of steers with genotype of 100 Hereford (H), 62/38 H Nellore (N), 50/50 HN, 25/75 HN. Twenty-four steers, twenty months old, feedlot confined by 126 days, were used. The diet with 12.7% of crude protein, was constituted by 57.5:42.5 forage to concentrate ratio on dry matter (DM) basis. The forage was corn silage + chopped sugar cane (relation 1:1). The regression was significant for the average daily weight gain (<IMG SRC="/img/revistas/rbz/v29n1/5726fr2.gif" > or = .59910+ .02068X- .00013X²; r²= .8890; P<.0041), daily DM intake (<IMG SRC="/img/revistas/rbz/v29n1/5726fr2.gif" > or = 4.76025+ .13037X- .00099X²; r²= .9369; P<.0010), DM intake per metabolic weight (<IMG SRC="/img/revistas/rbz/v29n1/5726fr2.gif" > or = 67.64281+ .60047X- .00475X²; r²= .7883; P<.0206) and expressed as percentage of live weight (<IMG SRC="/img/revistas/rbz/v29n1/5726fr2.gif" > or = 1.9217 + .0169X - .00012X²; r²= .6624; P<.0466), with X as the percentage of H. The average daily gain was lower for 25/75 HN steers which also showed the lowest DM intake. The dry matter intake per metabolic weight was higher for 62/38 HN, followed by the 50/50HN, and lower for 100H and 25/75 HN. The feed:gain ratio was not affected by the genetic groups. There was an expressive decrease in steers daily weight gain, when the proportion of Nellore surpassed 50%.
Bos indicus; Bos taurus; crossbreeding; performance
