INFLUENCE OF DITARY TRYPTOPHAN SUPPLEMENTAL ON PRODUCTIVE PERFORMANCE OF SINAI BEDOUIN LAYER HENS

This experiment was conducted in the Poultry Research Farm and the Poultry Nutrition Laboratory, Faculty of Agriculture, Minufia University, Shebin El-kom, in order to investigate the effect of dietary tryptophan (Trp) supplementation on Production performance, egg quality traits and some blood constituents of Sinai Bedouin layer hens were fed on supplementation during the period of 26 to 38 wks of age were determined. Economic efficiency and phonetic correlation between some productive parameters at the different levels of tryptophan supplementation were calculated. Results showed that final body weight and weight gain were significantly (P≤ 0.05) higher by increasing of tryptophan level. Hen–day production percentage, egg number, egg weight and egg mass were significantly improved as the level of dietary tryptophan increased. Feed conversion ratio was significantly (P ≤ 0.05) improved. Pronounced effects on egg shell percentage and thickness were significantly noted. Albumen, yolk and Haugh units were improved by adding tryptophan at the level of 0.23% of laying diets. Other traits of egg quality were not significantly affected by higher tryptophan levels. High positive phenotypic correlations between some productive parameters and final body weight was noticed by increasing tryptophan levels. Significant phenotypic correlation between egg weights and some egg quality traits by increasing tryptophan levels was recorded. There was a significant increase in plasma total protein, globulin concentration resulted from dietary tryptophan. No significant differences were determined in transaminase enzymes (ALT and AST) plasma blood concentration between all treatments significantly reduced the levels of total cholesterol and triglycerides concentrations. Finally, it could be concluded that dietary tryptophan might have positive effects on productive performance, economic efficiency and health status of layer hens. In respect of Sinai Bedouin laying hens diets 0.23% tryptophan could be recommended for improve most of economic traits.