Growth Performance, Immune Response and Carcass Status of Broiler Chickens Fed Diets Contain Different Sources of Methionine

Abstract

An experiment was conducted for a period of 42 days to assess the possible substitution of synthetic DL-methionine (DL-Met) by herbal methionine (H-Met) with graded levels on growth performance, immune response and carcass traits of broiler chicks. A total of 150-day-oldArber Acer chicks were randomly allotted into five experimental groups (30 chicks/group), each group with three replicates of 10 birds per replicate. Group 1 of birds was kept as a control group and the birds fed the basal diet containing the full methionine requirement (100%) from DL-Met without any H-Met substitution. While, other experimental groups fed on basal diet with DL-Met / H-Met at percentage of 75/25, 50/50, 25/75 and 0/100 for groups 2 – 5 respectively. The results showed that, 50% replacement of DL- Met by H- Met improved (P≥0.05) final body weight and weight gain by about 2.2% and 2.3% respectively when compared with chick of control group. H- Met inclusion had no effect on feed intake, while 50% replacement of 50% of synthetic methionine by H- Met non-significantly (P≥0.05) improved FCR, PER, EEU and PI by about 2.1%, 2.4%, 2.2% and 4.2% respectively when compared with the control. 50% replacement of synthetic Met by H- source non-significantly reduced blood serum triglyceride, cholesterol, GPT and ALP when compared with the control. 50% of synthetic Met replacement by H- Met synergistically together and had immune-stimulant effect and lower fat liver content of broiler chickens.