An experiment was carried out to evaluate the performance and feed cost of barrows and boars fed or not with amino acid supplemented diets. Forty-eight animals were used with initial weight of 38.8±0.2kg distributed in a randomized block design with three treatments, being barrows males (CM), boars males (IM) and IM supplemented with 5% of amino acids (IM+5% AA). The treatment had no effect on body weight and weight gain. Feed intake, feed conversion ratio and feed cost were different (P<0.05) among treatments. Average feed intake was of 2.43kg, and the intake observed on CM (P<0.05) was higher at 5.5 and 5.2% in relation to IM and IM+5%AA, respectively. Feed conversion ratio was of 2.28, and the CM showed the worse conversion (P<0.05) at 6.2 and 11.6% in relation to IM and IM+5%AA, respectively. Average feed cost was of R$ 1,82kg-1, being higher (P<0.05) for the CM in relation to IM and IM+5%AA. The sex category (barrows or boars) and amino acid supplementation did not affect body weight and weight gain, but alter feed intake, feed conversion ratio and feed cost.
nutrition; weight gain; feed efficiency; males
