the effects of l-arginine supplement on growth, meat production, and fat deposition in broiler chickens

the objective of the present study was to investigate the effects of dietary l-arginine on performance, meat production and its chemical composition, carcass fat deposition, intestine morphology and blood parameters of ross broiler chickens during 46 days. in this experiment, 192 day old commercial female ross broiler chicks were used with 4 dietary treatments and 4 replications in a completely randomized design. dietary treatments included 100, 153, 168 and 183 percentages of digestible arginine, based on the ross catalogue recommendation. on 46th day of experiment, three chickens per replication were selected randomly, blood samples were collected from each, and thereafter they were slaughtered in order to measure carcass traits, intestine morphology and meat chemical composition. the results showed that dietary arginine treatments caused a significant increase on body weight, carcass efficiency, muscle yield, protein and fat content of muscle, heart weight, and growth of small intestine, while decreased abdominal fat weight. arginine supplementation increased plasma concentrations of triiodothyronine and thyroxine, but reduced plasma concentrations of cholesterol, triglyceride, and urea. according to the results of this study, consumption level of 168% digestible arginine, based on the ross catalogue recommendation, had the best results on growth improvement and carcass traits, while consumption level of 183% digestible arginine had the greatest fat carcass reduction.