Synthetic amino acids on the efficiency of utilization of an alternative protein source (Vigna unguilata) for broilers

Sun-dried ground grain of Vigna unguiculata cv. INIFAT-94 was assessed lu d etermine the maximum level of inclusion for the replacement of soybean cake meal and the effect of amino acid supplementation on the efficiency of uti lization. 1750 broilers of a Cuban commercial hybrid from 1 to 42 days old of bath sexes were used with increasing levels until completely substitutin g imported soybean meal by vigna meal. Synthetic amino acids (SAA) were sup plemented according to NRC (1994) or with an extra addition of 15% for meth ionine + cystine and 10% for lysine. in a completely randomized design with a factorial 5 x 2 arrangement. In a second experimental study with 630 chi cks of the same hybrid, from 7 to 49 days of; age, 35% of the soybean meal was substituted by vigna grain meal to eliminate SM supplementation in the finishing stage (35 to 49 days). The maximum substitution level compared to tile control was 50% without differences. In no case was there interaction between the substitution of soybean level by vigna and that of SAA, which indicates that an additional supplementation was not necessary. Between the control and vigna diets with or without SAA in the finishing stage, there were no differences for Final liveweight, conversion, viability and breast 1 yield. On considering feeding expenses, it was demonstrated that the prod uction of I I of meat;was cheaper when substituting the imported soybean by raw vigna, even with a 75% substitution. Besides the benefit derived from the partial substitution of an imported protein source, there is also a sav ings in foreign currency since there is no need for SAA supplementation in the finishing stage. It is concluded that Vigna unguiculata is an alternati ve protein option that does not require more amino acid inclusions than a c onventional diet, and in the finishing stage they are not needed giving a s ignificant savings in foreign currency.