Document Type : Research Paper
Assistant Professor, Faculty of Agricultural Science, University of Tabriz-Tabriz
Professor, Faculty of Agricultural Science and Engineering, University of Tehran-Karaj
Assistant Professor, Sari Agricultural Sciences & Natural Resources University
The objective of the present study was to determine the effects of feeding high levels of L-arginine on growth performance, blood metabolites, and carcass meat quality of female Ross broiler chickens at the starter period. In this experiment, 192 day old chicks were fed with 4 dietary treatments (100%, 153%, 168% and 183% of digestible arginine, based on the Ross catalogue recommendation) with 4 replications in a completely randomized design from day 1 to 10. On 10th day of experiment, chicks were weighed, feed consumption was recorded, and feed efficiency was calculated. Also, three chickens per replication were selected after sampling, blood were euthanized to measure breast and thigh muscle weights, meat quality of the breast muscle (color, pH, and shear force). Data were analyzed based using proc GLM of SAS software. According to the results, the highest increasing percentage for body weight (2.33%), feed efficiency (6.35%), relative weight of breast (22.16%) and thigh (17.53%) muscles were observed in diet with 168% digestible arginine relative to control group (P<0.05). Also, the highest increasing percentage in plasma triiodothyronine (60.45%), thyroxine (26.91%), and relative triiodothyronine to thyroxine (25.91%) was observed in diet with 183% digestible arginine relative to control group (P<0.01). On the other hand, in 183% digestible arginine group noticeable decrease in percentages of plasma cholesterol (14.93%) and triglyceride (25.19%) concentrations, shear force (26.39%) and 24 (2.05%) and 48 (2.63%) h meat pH was observed(P<0.05) relative to the control group. The overall results of this study showed that consumption level of 168% digestible arginine, as based of Ross catalogue recommendation, had the best desirable results on growth, meat quality andplasma metabolites.