This experiment was carried out to study the effect of ionophore drugs (Salinomycin, Lasalocid and their combinations) on the performance of broiler chicks. Also their relationships with methionine (three levels) were evaluated. 1215 one-day-old commercial broiler chicks (Arian) were divided into 81 groups, 15 chicks per group, and tested in a completely randomized design with a 3×3×3 factorial experiment. Three drug types with three levels (0.0, the recommended level and 1.5 times the recommended level) of drugs and three levels (0.0, 0.1% and 0.2%) of supplemental methionine were used.
The results indicated that the effect of sex on plasma cholesterol and triglyceride, percentage of bone ash and percentage of abdominal fat was significant (P<0.0l). Drug type had no effect on the characteristics under study. Drug level influenced percentage of bone ash, percentage of eviscerated carcass, and percentage of abdominal fat significantly (P<0.0l), (P<0.01) and (P<0.00l), respectively. Also methionine level influenced cholesterol and triglyceride (P<0.0l) significantly. Interaction effect of drug type and drug level on plasma cholesterol and triglyceride was significant (P<0.05). Interaction effect of drug and methionine level on cholesterol and triglyceride was significant (P<0.0l). The results showed that levels of this drug influenced carcass composition and also supplemental methionine had no influence on the modulating effect of these drugs on carcass composition.
