عنوان مقاله [English]
This investigation aims to evaluate the role of dietary tryptophan on the growth performance carcass synthesis of fingerlings of Caspian Roach (Rutilus rutilus caspicus). Fingerlings (mean weight: 1.91 ±0.01 g and total length of 6.21±0.07 after adaptation were divided to 3 groups (0.25, 0.5 % of diet and one control (0%)). Mean weight and total length difference of treatments were not significant. Carcass synthesis (without head and skin) and body composition showed significant difference between treatments (p<0.05). Lipid content of body decreased significantly as tryptophan increased (p<0.05). Effect on food intake in higher vertebrata and fish is a result of tryptophan which increases serotonin levels of brain and can effect on weight gain and also can increase protein content of carcass and decrease lipid content in Roach.