دانشگاه تهران مجله تحقیقات دامپزشکی (Journal of Veterinary Research) 2008-2525 63 3 2008 09 22 STUDYING THE EFFECT OF DIFFERENT LEVELS OF METHIONINE AND FAT ON SOME ECONOMICAL TRAITS OF BROILERS بررسی تاثیر سطوح مختلف متیونین و چربی گیاهی بر برخی صفات اقتصادی جوجه گوشتی 203 208 23720 FA سید حسین نژاد سجادی گروه علوم دامی ،دانشکده کشاورزی جیرفت دانشگاه شهید باهنر مرتضی ستایی مختاری گروه علوم دامی ،دانشکده کشاورزی جیرفت دانشگاه شهید باهن جلال یوسفی دانش آموخته کارشناسی ارشد علوم دامی دانشگاه شهید چمران علی موسی پور گروه علوم دامی ،دانشکده کشاورزی دانشگاه شهید باهنر Journal Article The effect of3levels of methionine (NRC recommended, 5 percent more than NRC recommended and 10 percent more than NRC recommended) and 2 levels of fat (0 and 5 percent) on some economical traits (performance and carcass) of broilers using a 2x3 factorial experiment with completely randomized design based on two rearing stages, starter (0-3 wk) and grower (4-6 wk) was studied. ANOVA of the effects of dietary treatments on traits and Duncan's multiple range test to compare means revealed that methionine levels had significant effect on live weight gain and improvement of feed conversion ratio in starter (p0.05) but methionine levels decreased abdominal fat yield and increased breast yield significantly (pO.05). Therefore it can be concluded that using methionine up to 10 percent more than NRC recommended and fat up to 5 percent of diet, except in starter, is recommendable in broiler diets The effect of3levels of methionine (NRC recommended, 5 percent more than NRC recommended and 10 percent more than NRC recommended) and 2 levels of fat (0 and 5 percent) on some economical traits (performance and carcass) of broilers using a 2x3 factorial experiment with completely randomized design based on two rearing stages, starter (0-3 wk) and grower (4-6 wk) was studied. ANOVA of the effects of dietary treatments on traits and Duncan's multiple range test to compare means revealed that methionine levels had significant effect on live weight gain and improvement of feed conversion ratio in starter (p0.05) but methionine levels decreased abdominal fat yield and increased breast yield significantly (pO.05). Therefore it can be concluded that using methionine up to 10 percent more than NRC recommended and fat up to 5 percent of diet, except in starter, is recommendable in broiler diets https://jvr.ut.ac.ir/article_23720_283062995206f8cbf7c0b50216b9623e.pdf