RESUMEN
BACKGROUND AND OBJECTIVE: Terbutaline is a ß-agonist that used as growth promoters to improved carcass chemical composition of chicks without residues. The purpose of the present investigation is exploring the effect of different dietary levels and duration of terbutaline on the productive performance, biochemical and carcass quality traits including residue of acres broiler. MATERIALS AND METHODS: A total of 150 one-day-old arbor acres broiler chicks were allotted into 5 groups (3 replicates per each). Group 1 was fed on the basal diet without supplement, while groups 2-5 fed on the basal diet supplemented by 5 or 10 mg terbutaline kg-1 diet during 1-42 or 21-42 days, respectively. RESULTS: When handling the dietary levels and duration of terbutaline, results of the present study showed that10 mg terbutaline kg-1 diet during the whole experimental period is a more effective dose for improvement of growth performance with significant (p<0.05) increased serum protein and breast muscles relative weight compared with control. Also, 10 mg terbutaline kg-1 diet during the whole experimental period significantly (p<0.05) increase d CP% (crude protein%) and CHO% (carbohydrate%) of breast muscle and significantly (p<0.05) decreased fat% (ether extract%) of breast muscle and abdominal fat relative weight compared with control. Meanwhile, 5 mg terbutaline kg-1 diet during 1-42 or 21-42 days has no significant effect on the above-mentioned parameters. Regarding residue, the terbutaline residue wasn't detected in broiler meat. CONCLUSION: It can conclude that 10 mg terbutaline kg-1 diet during the whole experimental period is a better dose and duration for improving growth performance, the chemical composition of breast muscle and carcass traits of broiler chickens with no terbutaline residue in breast muscle.
