determination of methionine requirements of arian broiler chickens by using performance responses in the starter period

in order to determination the methionine requirement of arian broilers chickens during the starter period, a trial with 700 broiler chickens in a completely randomized design with 7 treatments, 5 replicates and 20 chicks in each experimental units was performed. experimental groups were consisted of 0.38, 0.43, 0.48, 0.53, 0.58, 0.63 and 0.68  % of methionine. other amino acids provided higher than the recommendation. broken line equations were used to determine the methionine requirement. body weight at the age of 7 and 14 days, with weight gain and fcr during days 0-7 and 0- 14days were affected by different levels of methionine (p<0.05). broken line models were fitted only for fcr at the age of 7 days. methionine requirement for this period were 0.51 %. the feed and product prices (live weight) were used by order of maximum benefit to determining methionine requirement. methionine requirement for this method were 0.55 percent