Improving the Utilization of Broiler Low Protein Diets Using Tyrosine, Tryptophan, Citric Acid and Sulphate

Abstract

The aimed of this study evaluate the ability of tyrosine, tryptophan, citric acid (CA) , sodium sulphate (SS) or their mixture to improve the utilization of broiler low protein diets (LP diet). A total number of 270 Cobb broiler 10 day old were randomly distributed into nine groups received basal diet (control), diet containing 2 percentage points lower protein (LP diet), LP +0.3 % citric acid (CA), LP +0.3% Anhydrous sodium sulphate (SS) , LP+0.3 % CA + 0.3 % SS, LP+ 0.05% tyrosine , LP +0.05% tyrosine + 0.3 % CA +0.3 % SS, LP+0.05% tryptophan and LP+0.05% tryptophan +0.3 % CA + 0.3 % SS. At 21 day, using LP diet significantly decreased broiler body weight compared to control diet while all feed additives improved weight gain and feed conversion compared to LP diet. The birds fed mixture of tyrosine +CA+SS recorded the highest value of body weight and the best feed conversion. At 35 day, The birds fed mixture of tyrosine +CA+SS recorded significantly higher body weight value and better feed conversion by 8.63 and 8.53 %, respectively, compared to those fed control diet . Compared to other treatments, birds fed mixture of tyrosine +CA+SS recorded the highest values of total protein, albumin and total cholesterol in plasma. It can be concluded that addition of tyrosine, tryptophan, CA or SS to LP diet improved the broiler performance to be like those fed control diet while the mixture of tyrosine +CA+SS surpassed the control.