Effect of different substitution levels of extruded soybean with soybean meal and different dietary vitamin E levels on production index and economic traits of broilers

An experiment was conducted in order to study the effect of different substitution levels of extruded (ESB) with soybean meal (SBM) and two dietary vitamin E levels on production index and economic traits of broilers. 264 Cobb 500 day-old chicks of either sex were distributed among 24 groups of 11 chicks per each experiment was exerted as a 4×2 factorial arrangement (4 substitution levels of ESB with SBM: 0, 25, 50 and 75 % and two dietary levels of vitamin E, 42 and 75 IU/Kg) with three replicates in a completely randomized design (CRD). The results showed that different substitution levels had no significant effect on production index at 28 and 42 days of age (P>0.05). However recommended levels of vitamin E significantly improved production index at 28 days of age (P<0.05). The interaction effect of different substitution level of ESB with SBM and vitamin E supplement on feed cost at 28 days and feed cost per live weight gain at 28 and 42 days was significant (P<0.05). As increases each of them increased costs. Monetary return at 42 days of age was significant (P<0.05) and increase of monetary return was showed. It can be said that different substitution levels of ESB with SBM plus higher level of dietary vitamin E had not any negative effect on economic status and production index of broilers.