Evaluation the Herbal Methionine as a substitute of DL-Methionine and effect on performance, carcass characteristics and blood metabolites in broiler chickens

This research was conducted to evaluate the effects of synthetic methionine replacement with herbal methionine (HM) on performance, blood biochemical parameters and carcass characteristics in broiler chicken. A total of 280 8-old Ross 308 male chicken were randomly assigned to 7 dietary treatments: control, in which 100% methionine requirement was supplied form DL-methionine, and in treatments 2 to 7, DL-methionine in control was replaced by 20, 40, 50, 60, 80 and 100% HM, respectively. Each treatment replicated 4 times (10 birds per each). Body weight at 21 and 42 d in broilers fed HM in levels up to 60% and 50% replacement was similar to those fed control diet, respectively. Experimental treatments had no significant impact on feed intake during the trial. No differences were observed in carcass percentage and relative weights of abdominal fat, breast, tights, liver, heart, thymus, lien, and bursa among the treatments. Herbal methionine replacement had no significant effect on blood total protein, globulin, uric acid and triglyceride content. Concentration of serum albumin was significantly elevated in birds fed diets contained 80% HM, whereas cholesterol content in treatment 100% HM and glucose content in treatments 60, 80 and 100% HM significantly reduced in compare to control (P≤0.05). In conclusion, it could be feasible to use herbal methionine in broiler diets as a replacement to supply a part of the methionine requirement without negatively affecting performance or carcass traits.