Abstract

The experiment was carried out to determine the optimum levels of dietary tryptophan (Trp) to investigate the growth performance, meat yields and cost effectiveness of commercial broiler chickens. A total number of 576 day-old Cobb 500 straight run broiler chicks were used in this trial. Four dietary treatments were considered for comparison and each treatment had eight replications with 18 birds per replication. A corn-soya based basal diet was formulated. Diets were provided into two different phases: starter and grower phase. Starter diet was fed up to 21 days and grower diet was provided for 22-35 days. First group of chicks fed basal diet considered as control diet (Trp 100%), the other experimental treatments (T2 to T4) were supplemented with increasing levels of tryptophan (Trp) at 115%, 130% and 145% respectively where recommendation is 100%. Birds were kept under identical conditions of management throughout the experimental period (0-35 d). Performance parameters were recorded on a weekly basis and the meat yield traits were measured at the end of the experimental period. Trp supplementation at increasing levels significantly (P

Key words: Tryptophan, Performance, Meat yield, Profitability