تأثير الإحلال الجزئي للبيتين و الكولين محل الحامض الاميني الميثايونين في العليقة على صفات ذبائح فروج اللحم

This study was conducted at the poultry farm, department of Animal production, College of Agriculture / University of Al-Qasim Green. The field work of this study was performed during the period from 20 / 2 / 2014 until 2 / 4 / 2014 and then followed by the laboratory work. The project of this study was aimed to identify the effect of utilization of betaine and choline and their synergistic mixture to meet the deficiency of methionine which could happen on the diets in production performance and physiological traits of broiler chickens. Three hundred unsexed broiler chickens strain of the commercial Rose (Rose-308) was used in this experiment. The chicks were reared on a litters floor and treated from the age of one day until 42 days. The chicks were randomly divided into 5 treatments and by 4 replicates per treatment, and each treatments was included 15 chicks and as the following: (T1): Positive control containing the standard level of methionine. (T2 Negative control containing half of methionine standard needs. (T3): Negative control and betaine (800mg/kg feed). (T4) : Negative control and choline (800mg/kg feed). (T5) : Negative control , betaine (400mg / kg feed), and choline (400mg / kg feed). The most important results of this study could be summarized by the following : The T3 treatment was surpassed the T2 treatment in the dressing percentage. Significant reduction (P < 0.05) in abdominal fat for T3 birds treatments compared with the rest of the treatments. Add to that, significant elevation (P < 0.01) concerning the weight of the chest muscle and the total weight of the chest meat for T1 and T3 treatments for T1 and T3 treatment birds compared with T2 treatments birds.