Vigna, an alternative protein source for poultry in the tropics. Preliminary results

Six hundred and thirty broilers of either sexes from a commercial hybrid were used to evaluate the effect of parcially substituting soybean cake meal by vigna (Vigna unguiculata var. INIFAT-93) sun dried and ground in a three-phase feeding system. The control diet was wheat-soya-fish meal and another diet with 35 % Of soybean cake substituted by vigna supplemented with synthetic amino acids according to the percentage of bioavailable amino acids and to the ME in the diet. A third treatment did not include synthetic amino acids in the vigna diet in the period of 36-49 days. The feed conversions (2.51, 2.52 and 2.57), weight gains (1.72, 1.74 and 1.72 kg/bird), viability (97.1, 94.6 and 98.9 %) and breast yield (26.3, 27.7 and 27.3 %) were similar between treatments in the order mentioned. Higher returns are due to the parcial substitution of an imported protein source by a tropical legume, the reduction of dietetic protein contribution and the lack of supplementation of synthetic amino acids in the highest inteke phase (54 % of total).