Resumen de The effect of using different energy sources and levels on carcass weight, breast muscle mass, mTORC1 and AKt gene expression in Cobb 500 broiler chicks

Sayed Mostafa Akbari, Ali Ashraf Sadeghi, Mehdi Aminafshar, Parvin Shawrang, Mohammad Chamani

• The present study was aimed to evaluate the effect of different energy sources and levels on carcass weight, breast muscle mass mTORC1 and AKt gene expression in Cobb 500 broiler chicks. A total of 600 1-day-old Cobb 500 broiler chicks with an average weight of 39 ± 0.50 g were randomly divided into five treatments. Each treatment was further divided into four replicates. Chicks were fed by basal diet based on corn and energy level by Cobb 500 instruction manual as control group, basal diet with 3% lesser energy than control (T1), basal diet with 6% lesser energy than control (T2), basal diet based on corn and fat level according to Cobb 500 instruction manual (T3), basal diet based on corn and fat with 3% upper energy (T4) for 42 days. To assess carcass characteristics two chicks of each replication were slaughtered and weighted after picking the carcasses. After DNA extraction, the UV spectrophotometric method was performed for determines the quality and quantity and Real-time PCR was performed on the corresponding cDNA synthesized from each sample. Data from this study showed that there were significant differences about carcass and breast muscle weight between treatments (P <0.05). As result obtained from this study the highest mTORC1 and AKt gene expression were for T4 and T3, T2, T1 had higher gene expression compared to control respectively. In conclusion higher levels of energy are needed for Cobb 500, for both mTORC1 and AKt gene expression as well as the more carcass and breast muscle influences.