At a local poultry feed plant, a study was conducted to evaluate the effect of dry or steam conditioning in different times and levels of activated sodium bentonite (ASB) on the physical pellet quality indices and pelleting energy usage of wheat-based diets. In a 3×3 factorial arrangement of treatments, three ASB levels (0.00, 0.75 and 1.50%) and three conditioning time (0, 2 and 4 minutes) along with or without steam conditioning (0.0 time as dry-conditioning), 2 and 4 minutes (70°C- steam conditioning) were evaluated. Physical Pellet quality indices, including pellet durability index (PDI) and pellet hardness were determined in a Holmen Pellet Tester (NHP100) in four different times (30, 60, 90 and 120 seconds) and Kahel pellet Hardness tester, respectively. Electrical energy consumed for pelleting was calculated as relative electrical energy usage (Kwh/ton of finished feed). Steam conditioning (70°C) significantly improved PDI and pellet hardness when compared with that of dry conditioning group (P< 0.05). ASB addition increased the PDI in comparison with that of no ASB addition into the diets (P< 0.05). PDI at 2 minutes steam conditioning, and at 60, 90, and 120 seconds were higher than that of 4 minutes steam conditioning diets (P< 0.05). The diets conditioned for 2 minutes containing 1.5% ASB had the highest PDI (P< 0.05). Pellet hardness was not affected by this procedure. Relative electrical energy usage was decreased significantly at 4 minutes feed conditioning time than those of dry and 2 minutes conditioning (P <0.05). Therefore, steam and feed retention time in conditioner chamber can positively affect pellet quality and relative electrical energy usage.

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